Showing posts with label Brand-Lepai. Show all posts
Showing posts with label Brand-Lepai. Show all posts

06 July, 2015

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.

12 June, 2015

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 SoundstageWhat HiFiStereophileHiFi+, 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.