Almarro 318B Overview 6C33C Audio Professor

Brief Review: Almarro 318B, vs A205A Mk II and AES SE-1

After I rehabilitated the Almarro A205A and AES SE-1, it was the turn for almarro A318B, but not before overcoming a hiccup. Let's start with:

Overview: 6C33C

In the last two decades, this tube, used on MIG fighter jets, became (in)famous. For an Introduction, read this article in tubetvr. If you look at the spec's, unlike most tubes, this beast is low plate voltage, high current and dissipation. As mentioned, the big variations in tubes favor individual fixed bias. It requires an ultra-stiff power supply, which is why, for such an interesting tube, there are fewer than usual DIY efforts. Otherwise, its ability to deliver 20 watts in SE configuration and hence to drive real world loudspeakers would render it even more popular. But there are people who advises against using this tube for audio, particularly with fixed bias, as opined in jacmusic, which is an even better introduction. Suffice to say, frequent checking of bias is a must.

OTL In a way, the 6C33C is most famous for its use in OTL amps. I have never heard the Atmasphere Novacron, one of the earliest OTL amps. And no, I have never heard the ridiculously expensive Lamm. In HK, I heard many times, always to good effect, the Italian Graaf GM20 and Modena (see my OTL Overview and also here). Another friend also uses the original Tenor OTL Monoblocks (this one) to drive his Watt/Puppy and it was OK (still a mismatch imho, but then I don't take to Wilson, particularly the incoherent Watt/Puppy).

SE The Almarro A318B is actually not the first SE 6C33C amp that I owned. In HK, I still have an old 100V Japanese Audio Professor amp, which has Tango transformers and uses 4 x 6J5 (= 2 x 6SN7) to drive the 6C33C (see right pic, borrowed from the net; click to enlarge). Its sound is excellent and warmer than the Almarro. I once took it to my friend Paul's place, where I matched it with the Graaf GM20, driving the B&W 802N. The two sounded similar in tonality and detail retrieval, but I preferred the SE for its better bass.

Push Pull This is the least often seen. From the start, BAT has always had a PP model in the lineup (see Herb Reichert's recent review of one). I have heard it at shows, pretty good (usually shows don't yield good sound).

Almarro A318B
This amp is quite famous and needs no introduction. For details, read the 6moons review. The A318B uses a little NFB. I have owned this amp for a long time, but have never formally written it up. Recently, my unit developed a problem. As I have recounted in a previous article:

"...Almost a year ago, I took out my Almarro A318B for a run. The machine heats up the filaments for almost 2 minutes before unmuting itself. Soon I heard popping sound in the left channel and shut it down. The same the second time. It also would not bias (recommended is 0.18V; no more than 0.21V). I got frustrated and put it back into the box. Recently I decided to get a new matched pair of 6C33C, and they are not cheap (over $100). I installed the stock Russian 6SN7 and 6SL7 and ran the new tubes. Great music, no bias problem. The next day, I installed the same 2 old-stock N7/L7 which I have kept in the box, expecting a better sound. Guess what, a pop in the left channel! I went to test the N7/L7. The L7 tested great. The N7 passed but for one triode I saw the meter drift erratically in both directions. There! That 6SN7 is faulty! Yes, tubes can measure well and still be faulty, particularly when warming up. I exchanged it with a RCA 5692 and the sound was perfect. Humbled, I reflected on why I had assumed it was the 6C33C that was at fault. Why had I not considered the possibility of either of the small tubes being the culprit? Perhaps the biasing problem compounded my confusion. Yesterday, I swapped in the original pair of of 6C33C and, guess what, they worked perfectly. And this time, there is no bias problem; in fact, they bias just like the new pair. Well, what happened back then? Unlikely as it is, I could only surmise that the faulty tube somehow messed up the bias. Well well, this is as it should be. I never used this amp that much and the stock tubes still should have plenty of life left (especially since I now run them at only 0.13-0.15V bias; mind you in NYC my area voltage can be 126V, dangerously near the tolerance limit of gears designed for 117V +/- 10%). I could have saved $100 if I had been more thorough before..."

In the forums, some complain of popping noises. Some of these cases could be due to the 6SN7/L7! In my experience, the stock Russian 6H8 and 6H9 are not reliable at all, and early failures are not uncommon. In HK, I had another friend who had one and used it with the stock tubes for a long time with no problem. Even though my listening sessions are long, there is no bias drift. So, provided you check the bias frequently (easy in this amp), imho it is a reliable amp.

What about the sound? Well, of all the amps I have used with the Harbeth P3ESR SE, the A318B was the best. It surpassed the Akitika GT-102 in texture and color. Everything is just bolder and fleshier. Plenty of power. In comparison, the lower powered Almarro A205A Mk II and AES SE-1 seemed relatively subdued flatter. Not very tubey in sound, it is nonetheless highly listenable - a great amp and a classic by now, especially for those who need a little more power. Too bad Almarro is no more.

Almarro A205A Mk II Nagra BPS Micromega MyGroov Schiit Mani

Brief Review: Almarro A205A Mk II
Brief Review: Nagra BPS vs Micromega MyGroov vs Schiit Mani

Last time I tried to fire up my Almarro amp, it produced some crackling noise and I turned it off immediately. A few days ago I decided to try it again. I noticed the transformer fuse cap (not the power fuse; on the side) was not entirely properly seated so I corrected that. No problem now! Strange.

Almarro A205A Mk II
This amp needs no introduction. The younger (and more sensible) Jeff Day owned the original and reviewed both for 6moons (link for Mk II which contains link to Mk I). He preferred the the Mk I by a little, but only recently discovered that his Mk I had the stock caps replaced by Jensen (see Positive Feedback)! That is, the Mk I was sent to him for review without telling him that it had the coupling caps replaced!

This is not unheard of. Many years ago, in HK, we went to a shop to hear a bargain Chinese amp, and it sounded reasonably good. My friend insisted on the one on demo and took it away. Another friend who bought one never got the sound he heard at the shop, just slow and soft. Finally they compared the innards. Guess what! The demo was modifed to fixed bias from the original's auto-bias! Of course that sounded punchier! Deception! That's not all, some years later, someone's had a problem with one of the output transformers and found out that the big potted transformer only has a much smaller one inside! So, size and weight can still be deceptive.

Although 6moons was the only review at the time, this model sold pretty well, and you often see it turning up second-hand, many modified with V-caps by the dealers. I bought mine second-hand many years ago and rarely used it. I substituted it for the ss Akitika and used the 16 ohm tap for my 15 ohm loudspeaker in my Streaming System:

CDP: Micromega Stage 2 or Magnavox CDB-492
Bluetooth: Dayton BTR-01 digital out to Micromega MyDAC
Analog: Technics SL-1200 Mk II, Denon DL-103; Micromega MyGroov
Preamp: Yamamoto CA-04L

I started with an RCA 12AX7 and a pair of Sovtek EL84. I was immediately grabbed by the excellent sound. Although just 4.8 wpc, it did not sound anemic at all. As a matter of fact, the bass was fuller and better shaped than the Akitika amp! There was a trace of leanness at the top. I rolled in a pair of old-stock Mullard's (one of their better tubes). Now, very sweet indeed! It really doesn't need a preamp. I used it directly and it was just as beautiful, but I need more than 2 inputs.

This is an amp with a very small footprint, yet it is laden with features. 2 inputs, headphone output at the back (decent) and, best for people like me, choice of 8 ohm and 16 ohm taps instead of the more usual 4 and 8 ohms. It generates some heat, but is not excessive. A great choice in a smaller space.

I did open mine. Guess what! Although the designer recommended value for the coupling cap is 0.01 to 1.0 (stock is 0.047), mine is 2.2 Sonicap!!! Someone before me must have wanted for bass! However, after listening for days, I don't think there is anything that I need to change, the bass certainly was not slow nor bloated, though one day I may still restore it to official value and see what it is like. Also, the signal wires going from the volume pot (below pic, silver colored) to the 12AX7 look different from the pics of Jeff Day. I was suspecting they were changed too. I googled the cached pictures of the many second-hand units and found a couple identical to mine, so I concluded they were stock. Power supply caps can be different too. So Almarro had some variations over its production span. My unit (serial # E16869) is likely a later unit.

For not much money on the second-hand market, often with extra's, this is an excellent starter SE amp employing one of my favorite tubes. The Almarro is definitely better than the Wavelength I heard more than 20 years ago (not the Junior, likely a simpler precursor). I'd advise those interested to look at the innards carefully to see whether there had been mods.

pic of BPS from 6moons.

Nagra BPS, Micromega MyGroov vs Schiit Mani

There is no miracle. Although the Schiit Mani is a good buy, it is outclassed.

The Nagra BPS is a fantastic battery operated phonoamp which I have written about here. It is not cheap, but I regard it as a bargain. In this system its incisive (but not oppressively so) nature is displayed to perfection.

The Micromega MyGroov also shines even more than before. Its detail retrieval is more than Schiit, almost approaching Nagra, while tonally it is warmer than the BPS. It is staying in this system. MyGroov is now not available stateside, but in Europe and The UK you can get one for Euro/GBP 200 (including VAT), a great bargain!

Elekit TU-8150, Almarro M1A, Dayton B652, JBL L20T, Micromega MyDAC

Dayton B652 on top of Almarro M1A. Click to enlarge.

Elekit TU-8150 (DX), Part III
Almarro M1A vs Dayton B652 vs JBL L20T
Review: JBL L20T, Part III
Review: Micromega MyDAC, Part III

*Elekit TU-8150: Part I (Basic Info; 6AQ5 vs 6V6), Part II (Pentode vs Triode; Input 1 vs 2), Part IV (Input 2 mod).

*JBL L20T: Part I (Basic Info), Part II (partnered by SMSL T-Amp, interesting contrast to partnership with Elekit).

*Micromega MyDAC: Part I (Basic Info and Test), Part II (loose ends, including desktop).

I didn't really want to switch out my big horns, but in the name of thoroughness, there was still ground to cover. I tried out other smaller loudspeakers for a glimpse into real-world compatibility, so as readers and potential buyers can judge for themselves.

Horses for Courses In so doing, I discovered that, due to the design, it was more complicated and time consuming than I anticipated and I had to re-think and even partly unlearn what I had found before. However, as a result, I learned more than I thought I would! Now, I am pleased.

Due to the issues involved (differences in gain structure between the 2 inputs, as well as the presence of an Op Amp preamp stage), the Listening Notes are organized a little differently from usual. Readers should cross-reference with Part II for best understanding.

For most of the listening I used my System II front-end: Sony XA5400ES CDP; Thorens TD-125/SME 3019i/Denon DL-304; Aurorasound Vida Phonoamp;  Shindo Monbrisson Full-Function Preamp. Cables are various Gotham for interconnects and Belden 9497 for loudspeakers.

Listening Notes

• The Reality of 2.9/1.6 Watts When it comes to such flea power, I probably have experienced more than most people, including SE fans. My own Sun Audio VT25/10 SET amp (estimated 1.5-2 Watts) worked reasonably well with my Klipsch La Scala. My 45 amp (estimated 2.5 Watts; DIY'ed by a friend) worked superbly well with both my La Scala and even Tannoy Canterbury. I have heard my friend's Sun Audio 6V6 SE amp work with his Altec 605, and another friend's Sun Audio 45 SET amp (same amp as the VT25/10, just slightly differently configured) work well with his Lowther. But certainly all flea powered amps are not all created equal, and the rated output power, like much else measured in hifi, is only an indicator. A 1.5 Watts Western Electric Push-Pull Amp, like the WE 46 (here) sounds a LOT more powerful than a SE(T) amp of equal or higher rating (the same also holds true of even higher powered SET amps - a Wavac or Verdier 300B sounds a whole lot more powerful than, say, a Spark 300B amp). Preamp For low-powered amps, it is usually highly desirable to have a preamp with good gain. You need all the help you can get for that first watt. Forget about "Straight Wire with Gain", or passive preamps (a TVC with gain may be an exception). So for most of the listening here I used my Shindo Preamp, and maxed out the volume of the TU-8150. Of course, the TU-8150 does have a preamp section in the form of an Op Amp, which makes things a little more complicated, as we shall explore. Volume Setting When used with a preamp, keep in mind that in the TU-8150 the volume pot is after the Op Amp, so it can be maximized when used as a power amp.

• Room Size and Effect For such flea-powered amp, I feel compelled to say something about my room, so as to put things in context. Mine is around 300 sq ft, large for small loudspeakers and low powered amp. However, as you can see in the pic, my bookshelves are in-room and near-field (my seat is right behind the Thorens TD-124 turntable), making it easier. Thus, the sound would have less bass than placement closer to the front wall (easier for the rear-ported Almarro and the front-ported JBL than the infinite baffle Dayton), but the room is well energized and the large and open soundstage is good compensation. But if your room is smaller (but not too small; otherwise you might as well go desktop), that helps.

• Loudspeakers Used Some of my smaller loudspeakers, like the LS3/5A's and Sonus faber Electa Amator are not good candidates. I round up the usual suspects. Almarro M1A The Almarro M1A is one of my favorite bookshelves (reviewed here). While I know the 89 db, 6 ohm loudspeaker works well with SET amps, I really wondered about one as low powered as the TU-8150. As we shall see, it was hardly a success. Dayton B652 This $30-35 loudspeaker is a wonder (reviewed here)! Although not for head-banging stuff, it does well with most acoustic music. Like the Almarro M1A, the B652 is also a 6 ohm loudspeaker. Its sensitivity is spec'ed at 87 db, lower than the Almarro, but it seemed to play louder and with more ease than the Almarro. I attribute this to its first-order crossover design, which usually are easy to drive (witness Loth-X, Reference 3A and B&W CM1, to name a few). Not at all a bad job, but... JBL L20T I dragged this pair out last, not expecting that much. It is a wonderful loudspeaker (reviewed here), but from my experience, large and classic JBL's usually prove to be much less SE amp friendly than Tannoy's of equal sensitivity rating, not to mention Altec and Klipsch. But this is the smallest model, which has about the same volume as Almarro, but much larger than the diminutive Dayton. It is rated at 87 db, same as the Dayton. Notably, the impedance rating is higher than both Almarro and Dayton, at 8 ohm. This may be of some import, as we shall see later.

• Op Amp In Parts I and II, with my 104 db horns, I preferred to bypass the Op Amp (removing it). And so I started this way. But with these smaller loudspeakers, even using the louder Input 1 the preamp volume had to be cranked all the way up. Even then the sound was not too dynamic. Obviously, for more inefficient loudspeakers, the Op Amp is necessary.

• Input I vs Input 2 I started with the less loud Input 2 (RCA). Both the Almarro M1A and Dayton B652 played pretty well, but it was clear the Dayton was louder and more lively. On orchestral music, the M1A's texture seemed a little thick in comparison, which I took to be an indication of not enough power. I then switched to Input 1 (with 3.5mm to RCA adaptor) and surely the sound immediately perked up, especially for the M1A. However, as the Op Amp is in use now, the preamp volume knob had to be carefully controlled as otherwise overloading can be heard (in the case of M1A). Even with no overloading, it was clear that, compared to Input 2, though more incisive, the sound lacked body (lean midbass and bass). What I am not sure about is if this is just a question of loading, or if the (low) quality of the 3.5mm adaptor has something to do with it. I thought to DIY an adaptor but that would have to wait.

• Ultralinear Previously, in Part II, using my horns, I preferred Pentode Mode to Ultralinear, and so with these smaller loudspeakers I started with Pentode. But the more I listened, even with careful attention to overloading, I found the distortion to be bothersome at high level. At first I thought that was due to clipping or overload. Remembering that Ultralinear reduces distortion, I switched back to Ultralinear and was amazed at the much cleaner sound.

• JBL L20T After I thoroughly tested the Almarro M1A and Dayton B652, I was a bit frustrated to be honest, particularly by the M1A. And so I hauled out the heavy vintage JBL pair with a heavy heart, so to speak. As soon as the music started I almost jumped out of my seat. GREAT stuff and a dream match that only happens once in a while! Everything became more three dimensional, more vital, and that tone! A revelation, Amen. Even using Input 2 the sound now had dynamics and scale that sounded like much larger loudspeakers. I had been listening repeatedly to Bernstein's exemplary late DG recordings of Copland's Appalachian Spring (LAPO) and Brahms 4th (VPO). All the loveliness and lyricism of the scores were brought out like nothing before, yet the proceedings felt tight and inexorable, which these scores also need. The volume was cranked pretty high up, but even with the Op Amp in place there was no undue "sandy" texture - mass strings had body and sheen. Only when the volume got really loud did a little bit of steeliness creep in, but that is expected as the distortion rises, and even pure tube amps would do the same. When I start discussing the music, you can tell I am beginning to really enjoy the music rather than just dutifully digging out facts for this article. Some albums I just had to play more than once. Kulanjan, the great collaboration between Taj Mahal and Toumani Diabate (Hannibal/Rykodisc) was simply stunning. The contrasting timbers of the guitar and the African Kora and the modulations of the 2 male and 1 female voices were effortlessly, and mellifluous. I know this album well, but as rendered by this humble pairing of Elekit and JBL, it is the best I have ever heard it. Rhythmically it has more swing than even on my horns! And in Kancheli's Lament, every whisper of the violin (really low in volume) as well as volcanic orchestral outbursts were highly atmospheric. This combination gets to the meaning of all kinds of music! Phono Playback So far with the small loudspeakers I have tested only with CD. The extra gain required for Phono proved taxing for the M1A and even the B652. But it is a different story for the L20T. Through the Aurorasound Vida the sound was irreproachable, lively and detailed. On Neumann's Leipzig Gewandhaus Ma Vlast (a late 60's East German recording, first issued in the US on London LP, so many later reincarnations, including CD, were mostly of German origin), the tonal splendor of the Leipzigers and the majesty of the reading were utterly compelling. A great but little known recording, extremely well recorded to boot (as is usual for East German era stuff). Similarly, Haitink's first Mahler 9th (Philips) displayed a cavernous soundstage in which the famously warm Concertgebouw woodwinds played echt characterfully, and the burnished brass tone! And William Tell, in that greatest of all Rossini Overture recordings, Piero Gamba/LSO (my LP is a cheap latter-day Holland London pressing), had an adrenaline-infused and BIG sounding Alpine storm (which much predates Strauss' essay, and I heard a chirping woodwind figure that likely was quoted by Strauss). Wow!

• Direct In I wanted to see how the preamp fared without a preamp. I used System III's Theta Data Transport and connected it to my Micromega MyDac with a Belden 1694A, fed it into Input 2 and adjusted the volume using the TU-8150's volume knob. Wow! I must say I was wooed yet once again by the Micromega! The fantastic rhythmic expression was evident with Kulanjan. One day I'd like to match it up with my Sparkler (which I have brought with me to NYC). The sound was really lovely, and when I switched back to the Shindo it was evident the texture was thickened by tube. Some may prefer the greater incisiveness of Direct In, but when running multiple sources (phono) and playing large orchestral works the addition of a preamp adds needed weight and punch, considerable advantages for classical listeners like me. 

Comments

• Elekit TU-8150 in General Though all designed to a price point, all current Elekit products have a reasonably muscular sound and driving power. However, the TU-8150, being the lowest in power, does require the potential user to have a clear goal in mind. 6V6 The cheap and ubiquitous, yet legendary 6V6 tube again reveals its glory. What a sound! There is not much point to run it as a triode (halving its already meager power), since it sounds so good in Pentode (with horns) and Ultralinear (with smaller loudspeakers). Warm Up With the Op Amp in situ, around half an hour of warm up is needed for it to sound its best.

• Elekit TU-8150 for Desktop/Headphone Although I don't have a desktop at the moment, I have quite a bit of experience, and actually think this amp is well nigh perfect for desktop/headphone, and I am sure it was designed with such users in mind. Although low in power, Its superbly detailed and rhythmically sophisticated sound, allied to excellent headphone output, is ideal for the task. Dayton B652 The Dayton illustrates this. It may not be able to energize a room like the much larger JBL L20T can, but it never puts a foot wrong. If I were to build a serious desktop, I'd add a subwoofer (there are good choices even around $100) to flesh up the sound.

• Elekit TU-8150 for In-Room Small Loudspeakers As my experience shows, it may take some time and patience to come up with a suitable partner. Given the very close sensitivity figures of the 3 loudspeakers in question, I can only surmise that the success of the L20T is partly due to its more tube-friendly (higher) impedance (and in the link to my previous article on L20T provided above we know for sure its impedance curve is utterly benign). Based on my experience I'd say it is better in general to have loudspeakers over 90 db's in sensitivity. News Incidentally, recently both Stereophile and TAS recommended in their April issues an affordable high-sensitivity loudspeaker that those interested may want to look into (since you are reading this article, you are probably one). The former reviewed the $549, 96 db, nominal 8 ohm Klipsch RP-600M (not online yet, but read the review in sister website cnet); the latter the $900, 91 db (but 6 ohm) Tower JBL Stage A190 (here). Being a fan of both Klipsch and JBL, I'd love to hear them (unlikely). By my estimate, the Klipsch will surely work a treat (due to its super-efficiency and higher rated impedance), whereas the JBL will likely too. The good thing is, the TU-8150 is so small and light that you can take it to audition loudspeakers!

• JBL L20T This is a gem that surprises by its performance with 2.9 watts. It confounds me because my 5 db more sensitive, but much larger JBL 4312 (12" woofer) does not work that well with 300B (~8 watts). But, good news to me! I am not sure what I like most: the effortlessness, the sweet and articulate midrange, the warm mid-bass/bass, the intimation of a larger scale than the physical size would indicate. All of it! A thought on matching: in the L20T Part II (link above) what I wrote of my impression of L20T vs Almarro M1A when driven by T-Amp was not at all similar to this round. So, you have been warned that synergy is involved and extrapolation, like much reasoning and measurement in hifi, may not always hold court.

• Micromega MyDAC I have never previously heard my Micromega in my US systems. Suffice to say, this brief outing really tickled me! I prefer its sound to the flagship Sony SACD player - more rhythmic engagement and flow. As a matter of fact, just before this is written I briefly moved it to System II and did a direct comparison and my impression remains the same. Perhaps I shall write an article on this and Sparkler in the future. A killer budget DAC, no, a killer DAC, period.

Postscript: This article is long in the making. I am glad I was more than repaid for my efforts. The next installment may take a while. I have to get back my Elekit TU-8500 preamp, match it with the Elekit  for a listen and then roll its OPA2227 into the TU-8150. Salut!

Langevin 102 Preamplifier

L: Langevin 1961 Catalog, from internet (Preservation Sound); R: system upstream. Click pics to enlarge.

Letter from NYC (42) 2015 (4): Langevin 102 Preamplifier - My Reference System III
Review: Elekit TU-8500, Part VI Use as Buffer Amp
Review: Lepai 2020A+, Part II

Links relevant to this article:
Reviews of Lepai 2020A+, Part I; Dayton B652, Part III; Almarro M1A
Phonoamp Shootout (with Parasound JC3, Part II)
Elekit TU-8500 Review Part I (with links to II-V)


Casual got Serious
Compared to years past, I had less spare time during my stay in NYC this year, and what time I had were piecemeal. My large systems (see equipment list in sidebar) saw relatively little use compared to my "Casual System". This left me to ponder a drastic upgrade of the system to reference status - "casual" should also mean quality!

Acquiring the Vida, which can hook up two turntables in Reference System II, freed up the Parasound JC3. Also, I have long wanted to set up my professional Langevin preamp, which has enormous gain and . So I got the idea of using my Elekit TU-8500 as buffer amp, to control the listening volume. All sources are connected to the TU-8500 System is now as follows:

Digital: Sony XA-5400ES SACD/CDP
Turntable 1: Clearaudio Concept/Ortofon Kontrapunkt C
Turntable 2: Audio-Technica AT-PL120/Raos MC Mono
Phonoamp 1: Parasound JC3
Phonoamp 2: Elekit TU-8500
Buffer Amp: Elekit TU-8500
Preamp: Langevin 102
Amp: Lepai 2020A+ or McIntosh MC-2200
Loudpseakers: Almarro M1A or Dayton B652

Click pic to enlarge.

Langevin 102 preamplifier
Considering the innumerable roles audio play in our lives, it is appalling how poorly audio history is documented. Which is why we all should contribute a little.

History The best known Western Electric is the best documented, but its various spinoffs are less fortunate. Langevin is the most important of these (actually incorporated much earlier and long supplier to WE), but its history is barely documented on the internet. Its very close ties with WE is immediately obvious from the similarity of its products (at its peak in the Golden Era) to WE. The products are superior in every aspect, and deservedly escalate in value.

The professional world in which most Langevin products are used provide tidbits of information (see here, here, and here). Langevin products and consoles were widely used in recordings. The company lasted into the transistor age, and its name was later acquired by Manley, which did not seem to do so well by it.

Documentation Descriptions and Schematics on the 102 series (A-G) are available in original Langevin literature from vintagewindings. My unit looks to be the 102-B/F fitted with the optional 103-B (for more info on 103 A-C, see vintagewindings) input panel and has a matching 201 Power Supply. Also, from the technicalaudio site, you can get more useful Langevin info: Description of Various Line Series; 1952 Catalog.

Acknowlegement: most sincere thanks to the folks who selflessly put these valuable info on the internet for free. Salut!

Design and Tube Complement The 102 is similar to the more famous WE 106 preamplifier, which employs the famous WE 348 and WE 349 tubes. The 6SJ7 is electrically identical to 6J7 except for pinout. Mine was re-wired for 6J7 (with its top-cap), hence enabling use of WE 348. And WE 349 can be used in lieu of the output tube 6V6. Output is similarly transformer-coupled. The 103B panel is not used. Right now, I am not using WE tubes, instead Sylvania 6J7 and National Union 6V6. The 201 Power Supply can use both 5Y3 and 5U4 types. I have used both but settled with the Tungsol 5Y3 for less heat, as sonically it is as good as the We 422. My unit was restored by Master Huang 臺北黃老闆 in Tapei, who has restored numerous WE units, including a pair of WE 124 that I have. He has very high praise for the unit.

Gain Like the legendary WE 106, these being professional equipment not originally designed for home use, the gain is enormous. I am not sure of the spec but the 102A is in the vicinity of 55 db! My unit thus is configured for both fixed and variable outputs (I use the former). Hum is therefore a potential problem, especially with high efficiency speakers. It would be interesting to try out this for phono direct in (after only RIAA application and sans phonoamp)!

Setup and Sonic Impressions

• Settings The setup has three volume knobs, and setting is somewhat aribitrary, arrived by listening. The lepai 2020A+ was used as an amp, with volume around 12 o'clock. The volume of the Langevin (fixed output) was around 11 o'clock. With these settings, the volume knob of the Elekit TU-8500 hovered around 10-12 o'clock. The interconnect from the Elekit output to the Langevin input is very long (not desirable but of necessity), around 15 feet.

• General Sound I first listened to the system using the dirt-cheap Lepai amp, and the result shocked me, that is how good it is. I would think most of this is attributable to the excellence of the Langevin 102. The sound has strength in every department. Most importantly, it is superbly lively. Indeed, it gives my Reference System I (always cooler than reference System II) a run for its money, lacking only power and bass heft.

• Langevin 102 Particularly impressive is the pristine high frequency. A miracle, in fact, considering the input is through a very long interconnect and a buffer amp. I think there is not a little of the single-ended 6V6/349A quality here. You may want to know older Chinese vintage tube lovers dubbed the 6V6 tube 琴王 the king of string instruments. The sound is very similar to my WE 106 (in which I use WE 348A/349A), and that is the highest accolade. In passing, note too Shindo used to use the WE 349A in his Giscours. As with the 6V6, the sound can turn lean with bad recordings, but with most material the midband and bass are beyond reproach.

• Elekit TU-8500 I rolled in RCA 6201 black plates and the sound was so good I let them stay. So users should try 12AT7 family tubes too! Set to unity gain (actually 1.1), the Elekit performed flawlessly as a buffer amp. Its neutrality allowed the full flavor of the Langevin to emerge. Commendable! Too bad I do not have the iFi iTube on hand to compare (next year perhaps). Not surprisingly, it also functions very well as a phono amp for the Raos MC Mono cartridge (shall be covered in a coming article). With this, I think I shall conclude my series on this gem.

• Parasound JC3 As mentioned in my last article (roll down), with an Ortofon Kontrapunkt C, I played Willy Deville's Miracle (acquired after hearing it played in Audioarts) and was compelled to listen to the entire side, a luxury for me these days. The high gain of the JC3 is not needed in this setup (indeed a detriment) but its quietness was again proved in this very high gain setup - remarkable!

Article finished in HK.

Lepai 2020A+, Almarro M1A, Meridian Explorer, 47 Treasure 0547

Letter from NYC (40) 2015 (2): Lepai 2020A+ T-amp, Part I
Overview: Almarro
Review: Almarro M1A Loudspeakers
Review: Dayton Audio B652, Part III
Review: Meridian Explorer, Part I
Review: 47 Treasure 0547 USB DAC/Passive Preamp
Talk CAS: Meridian Explorer
Review: Sparkler Audio S303 CDP, Part I

Addendum: See Review: Lepai 2020A+, Part II.

As my big Aurorasound Vida and phono amp shootout is taking me more time than expected, I thought of writing something else first. This article was triggered by my recent purchase of a $15 amp. The write up should have been short and sweet but, as often with me, things rolled into considerable proportion, as you can see from the title and subtitles.

Previous Encounters with T-amps
Tripath chips (and similar others) have taken the world by storm, and deserve their success, as implementation is easy, cheap and consistent with the dutiful modern sensibilities of miniaturisation and conservation. I have never owned a T-amp before, but have encountered them often (brands include the early Sonic Impact to modern-day Trends, Topping, King Rex etc), usually in systems with efficient speakers (horns, Bastanis, etc). My general impression is that sound is usually good and smooth. As a matter of fact, not much to offend (unlike many ss amps), but nothing much to get excited either. Rhythm and pace and bass performance are usually not quite top-tier; harmonics are also invariably shortchanged (one reason why a seasoned SET lover would give T-amps a miss). I have also heard some "hi-end" products that employ Tripath, but just like hi-end D-amps, these just do not interest me at present (likely not in the future either). One thing I like about certain Tripath chips is their low power output which, according to this horn user and "first watt" adherent, is a good thing.

Pics from FF's. Click to enlarge.

Lepai 2020A+ T-amp
Lepai is a Parts-Express brand that offers many models. The 2020A+ is the most basic and a best-seller. Despite its giveaway price, it has received quite a few reviews; most are rather generic to be truly useful, but I do recommend these two articles in about.com and FF's electronics, for their commendably serious treatments and pics of the innards!)

PE must sell a whole lot of 2020A+ (usual price ~$28) for there to be so are many "Open-Box" specials available, which is how I got mine, at $15. It came with everything, but the wall mart and knobs have some minor scratches, nothing to dwell on. Why did I get one? Not for my desktop; I was thinking of installing a system in my kitchen (oily fumes despite ventilator; still thinking about speakers, maybe diy cheap Mark Audio?).

Ergonomics Minimal, but that is just fine by me. I had no need of the tone controls and kept them bypassed all the time.

Mods That a $20 amp becomes a favourite for mods attests to its sonic worth! There are many excellent threads on mods that range from easy (a few caps) to the epic. Try these in the Parts Express forum , Telefpreen and diyaudio (the last thread got started because the member thought it to sound, even stock, better than the Sonic Impact T-amp (now re-issued by Dayton/PE), the one that started it all and an older benchmark). I am pretty sure I will mod it when I have time for Part II!

Power Supply Upgrade As mentioned in those threads, upgrading the power supply rating will increase power and lower the chance of clipping. My PS is a current version (3A) but when I get back to HK I shall try it with a 5A supply (an old laptop PS). Yes, I do plan to take this thing with me, so wait for Part II!


pic of M1A from Audio technique.

Overview: Almarro

My first encounter with Almarro was in HK, my friend JCR33's A205MkII. I then went to the HK dealer's showroom, which was my first encounter with the M1A loudspeakers, driven by the A205MkII. Soon after, I heard the A318B at a friend's place. My impressions were generally good. When I later returned to the US, I ordered The A318B and the M1A in white ash. I then acquired a used A205MkII.

Almarro's Website has good links to all of the reviews.

A205MkII This is probably Almarro's most popular product. I have had experience with several other single-ended EL84 amps. The Almarro is not as subtle or refined as my little known vintage Conar integrated which, if my memory serves me, uses the same tube complement. Neither is it as mercurial as a friend's old Wavelength, though the Almarro's bass control is better. Run on NYC's high voltage of 123-125V, my sample shows a dull red glowing of the plates of the EL84's with NOS tubes, indicating overly high plate voltage; the tube is run hard.

A318B This is also a popular product. The "B" version is with negative feedback; the "A" is without. The designs are different (see the 6moons interview; link above) but the "B" version is certainly what most people have. Again, I have had quite a few encounters with the 6C33 tube before. In HK, I have an old Japanese Audio Professor custom 6C33 SET amp that uses quality Tango transformers; its sound is sweeter and fuller than the A318B, but the Almarro is more transparent, more like my friend's Graaf 6C33 OTL amp (which I once compared to the Audio Professor, preferring the latter for better bass control). With old stock 6SN7 and 6SL7 rolled in (a must; the Russian ones are terrible), the A318B delivers a well rounded performance, transparent, with good rhythm, control and drive for a SET amp. Grant you, the 6C33 is not as sweet or mellifluous sounding as more famous (and expensive) direct-heated triodes like 300B, 2A3, 45 etc, but Almarro's implementation gives you all the sophistication of a good SET amp, without the penalties of the bad SET amps out there (many, especially Chinese ones). The 6C33 can be a lean sounding tube, and its treble can be less than pristine, but the A318B gets it right.

Almarro M1A
Almarro's loudspeakers are much less well known than their amps (I do not know of anyone else who has a pair), which is a pity since they are reasonably priced. They also use self-designed drivers and sport good woodwork.

The M1A is the sleeper in the Almarro canon. There is virtually no info on the internet (HK dealer has a page in Chinese from a local magazine, the highly unreliable 發燒音響). A pity. As you shall see, it is a superb product. I hope my coverage addresses this negligence a little. Official spec's:

Drivers: 1x1.5" tweeter, 1x5" woofer
Frequency response: 50Hz - 26kHz
Sensitivity: 89dB
Impedance: 6 ohm (not on website; I filled this in as it says so on the back)

pic from What HiFi, exactly what my setup looks like.

Meridian Explorer
The Audioquest Dragofly started a trend of remarkably small USB DAC/headphone amps. I really don't use headphones much and do not need one, but the Explorer is recently discontinued and halved in price to make way for the Explorer 2 (which incorporates their proprietary, fascinating and potentially ground-changing MQA technology). As I have always been a fan of Meridian digitals (which since the 16-bit era to now has never faltered), I could not resist and bought one. Incidentally, this is my first 192-capable DAC (but I don't have a 192 file)!

The Explorer has been well reviewed. See Soundstage, What HiFi, Stereophile, HiFi+, and TAS (note Neil Gader uses only the line out, like I would!).

Setup It was easy as my Mac requires no driver. However, I did encounter an anomaly not mentioned in any of the reviews. As I only have AIFF files ripped from CDs (44.1) by iTunes, I was surprised that all 3 lights lit up, indicating 192 playback. I went to Utilities/Midi Player and discovered somehow my playback was at "192"! I set it to 44.1 and the two other lights went out, as it should. Then I remembered with iTunes you have to change the frequency each time as needed (which is why no "hi-res" users use it). Make sure you know your setting.

47 Treasure 0547 USB DAC/Passive Preamp
While 47 Treasure's 0147/0247/0347 got much press and accolades, this little passive preamp with a USB DAC slipped off the radar. I bought this for my friend Andrew, and for this article played with it a little to compare with the Meridian.

Like Elekit, 47 Treasure's USB DAC module is available by itself, cheaply, so people can just add one to their equipment. The USB DAC board uses discrete components and requires an external power supply (provided). The selector, volume pot and cabling are the same as in their 0147/0247 preamps.

I use it as a USB DAC, volume max to the Lepai amp.

Test Equipment
For testing, I put together an impromptu system:

CDP - Sparkler S303
CAS1 - MacBook Pro/iTunes/Meridian Explorer or 47 Treasure 0547
Loudspeakers A - Almarro M1A
Loudspeakers B - Dayton B652
USB cable for Meridan: Stock
USB cable for 47 Treasure: generic
Speaker cables for M1A: Acrotech 6N-1010
Speaker cables for Dayton B652: Belden 8471
Cable from 47 Treasure to Lepai: Mogami 2534

1/4" Cables As the Meridian uses 1/4" phono jacks and the Lepai has a 1/4" input beside a pair of RCA inputs, I made a 1/4" phono cable (single run of Mogami 2534 for stereo) and a 1/4" to RCA stereo cable (2 runs of slim Belden 8451). Connectors are Amphenol.

Sonic Impressions

• Lepai 2020A+ Using CAS/Meridian Explorer, from the word go, I was impressed. As noted before, like most T-amps, the sound was pleasing, but this little amp has more going for it. I was surprised by the full harmonic palette and by the rhythm and pace. Yes, the treble is slightly wiry but nothing indigestible. Normal listening is tremendous, but care needs be taken with the volume, as the amp crakles/clips when it is cranked up. Background is quiet. Much of the excellence also has to do with the Almarro M1A loudspeakers. When I switched to the Dayton B652, performance drops but is still very good. Within its very modest output, the performance is so good that for once I feel mods are justified and desirable (people on the net expend a huge amount of time modifying mediocre/worthless gears to make them "giant-killers"), and that is exactly what I will do in the near future. I find engaging/disengaging the tone control to make little difference. Since acquiring the Lepai, I have almost neglected my usual "casual" rig; as a matter of fact, I have completely reconfigured it, but that is for another article.

• Almarro M1A I have to confess this is actually the best sound I have ever got out of the M1A. I have previously driven them with the Almarro amps as well as Elekit 300B amp and McIntosh MC-2200, but the results were not as good as this time!  The M1A's have a very pure and extended treble (think silk dome old Proac's and Sonus faber's), allied to surprisingly good and taut bass (especially for a port enclosure). In these respects, the M1A's are as good as, or better than, many loudspeakers of similar size that I have owned/heard and written about (B&W CM1, Vienna Acoustics Haydn SE, etc). For the M1A I have always used an old but superior pair of Acrotech 6N speaker cables. But this combination somehow is the most astonishing, more personal, more at ease. Synergy, I scratch my head! Suffice to say the M1A's take time to yield their secrets. It could also be finally run-in, as I really haven't used them that much. Nancy King's sadly oop King on the Road (Cardas) just vibrates with primal energy (emitting from just three people, sans amplification!) and conveying fully the spontaneity of the performance. R2R specialist UltraAnalogue Recordings' only CD, the very well recorded Weijenberg and Lee, revealed all of the considerable youthful energy it holds. Bravo!

• Dayton B652 (See also my previous short reviews: Part I, Part II) Switching to the $40 Dayton  (wired with Belden) perspective changed a little. Images are further back and transients are not as fast. Music is just not as present and full-bodied. But make no mistake, there is nothing unpleasant about it. Not counting the source, this system costs less than $60 and sounds like a thousand bucks (provided you don't listen too loud). As I have mentioned before, there are some negative opinions on the B652 on the internet, but for me, no matter if I use partnering equipment that is cheap as the Lepai or expensive as my reference electronics, the results are fantastic. I love them! Soon I shall upgrade the cap and wires inside to see if even more can be gotten out of them.  

• Meridian Explorer I am very pleased, this little device is great! If you don't need the promised MQA streaming, this older version, equally capable of hi-res at 192 Hz,  at $150 is a steal. It doesn't put a foot wrong; for size and limited PS derived from the USB cable, it has very good rhythm and pace, good soundstage and scale. I tried briefly the headphone output with my new Grado SR-80e, and the sound was splendid. Any line out (as I am using it) tethered to a basic headphone amp (popular now for desktops, as one can see from the Schiit offerings) is a compromise, but the Meridian did well enough. I actually took my portable CAS setup to several friends' places, and it never shamed itself. The sound is quite neutral, more so than my Sparkler S303 CDP, which in comparison immediately shows its lean mid bass.

• 47 Treasure 0547 This little USB DAC board is a surprise! My experience tells me to believe in asynchronous USB, but this device (isochronous; correct me if I am wrong) surprises me to say the least. It holds its own against the Meridian Explorer. Even with the extra cabling and selector and volume pot in the signal path, I could detect little significant difference in all sonic parameters between the two. Given the natural supremacy of (good) British gears in PRaT, this is an achievement. DIYers who need a USB DAC board should well consider this.

HiFi Letter from NYC 2010 (1): Setting up (yet again)

HiFi Letter from NYC 2010 (1): Setting up (yet again)

It's 4:00 am.
What to do if you are wide awake after nearly a day on the jet? Dreaming about the feisty stewardess from Beijing whom you had talked to for hours on KAL? No such impractical things for me.

Time to set up my hifi. Hungry for some music, I started building the second-station first, though it is different and simpler than last year's incarnation. Remember the second-system is for really low-level listening at the wee hours (more on this in the same link). It must have excellent details at very low level. This year's version when I began:

Second-station
Digital: Linn Karik used as CDP
Preamp: ARC SP-9
Amp: McIntosh 2200
Speakers: Focal 705V

And as it is NOW, just a few days later:

Digital: Meridian 506-24
LP: Thorens TD-125/SME 3009/Benz-Micro Silver
Preamp: ARC SP-9
Amp: Almarro 205D (EL84 SE amp)
Speakers: Almarro M1A

This second system metamorphosed over the next few days. Things I noticed in passing:
-after I moved the Linn CDP to the main system, I substituted the Meridian. While the Karik sounded great as soon as I powered it on, this was not true for the 506. For several days I was not totally satisfied with the sound, but it came alive eventually. The 2 players should sound on par, though I'd give the Karik the edge still.
-the SE tube amp brought greater details, of course. It's amazing the efficiency of the Focal and Almarro speakers (despite their mid-80's db ratings)
-So did the Almarro speakers. Perhaps more on these when I have time.

Damn you, Maggie!

While I started to play some CDs which were delivered after I left NYC last time, I lost no time to build my main system. I decided this time it's going to be the Magnepan MMG. Damn those "proprietary" sockets and tiny screws and tiny allen wrenches!! After about 2 hours I managed to rebuild my main system, which is for another article. After all the strenuous work starting in the middle of the night, I was famished and went across the street for some FOOD. The sesame bagel with sausage and egg hit the spot, and the coffee lifted the spirits. Who said hifi nerds don't get enough exercise?

This year I experimented with many things in trying to bring the performance of Maggie closer to my beloved Martin Logan Source. It is impossible but the effort is worth it. Stay tuned.

It's pretty cold here for the end of March. Mom had the heat on, which helped her to keep her hard-boiled eggs warm.