26 September, 2022

Nagra VPA MSA Quad 77 909 Pass F5 Pamphonic 3000 Tektron

Click pics to enlarge. Top, One of the Author's many setups. Nagra PP 300B amp in center; VPA monoblocks flanking it, all driving the Tannoy Yorkminster.

Letter from Italy (22-3): M Surdi on What Make His Tannoys Tango

Editor: There is so much I agree with and want to comment on, but I want to preserve the densely textured wholesomeness of M Surdi's writing that I shall refrain and perhaps later write a companion article. Keep in mind his room is fairly big.

Previously, M Surdi wrote on his long Tannoy journey, an article not to be missed (here). The current article discusses the electronics matching during the long period.

We may take it as a given that all audiophiles are OCD afflicted. However, even terminal maniacs must balk at a blow by blow description of the decades long pairing of the four sets of Tannoys I have described in my previous post - some 25 different power amps and integrateds (and that’s keeping preamplifiers out of the mix).

Any credit accorded to my musings should also take into account the fact that musical proclivities may change with time. As an archetypal Sixties survivor, I’ve travelled the usual boomer arc from rock to baroque, Animals to Allegri, ZZ Top to Zelenka, and most alliterations in between. The Tannoys caught me in mid-journey, when punch and drive (represented by Tina Turner belting out Acid Queen, on AR-LST’s no less) were gradually giving way to midrange, proportion and all-around tone. This obviously had an impact on amplifier choice and preferences (though Biber’s Missa Salisburgensis is no chocolate box affair).

That being said, in order to cut through product clutter, I’ll be passing my judgments by amplifier categories: transistor, class AB to A; tube, push pull to SET; and class D; with some final comments on bi-amplification. With the intent of keeping things from getting even drier I’ll also be throwing in some gratuitous comments on mismatches and quirky combinations. Not, however, before raising Two Useful Signposts: best amp ever heard on Tannoy’s are the Nagra VPA monoblocs, hardly a surprise since these are the best amps I’ve ever owned (and sold off because of serious mental issues). Worst amp, and by a long chalk, is the noxious Meridian 551, a high powered sand amp which in conjunction with the equally toxic 501 all digital pre was so bad that even patriotic British reviewers could only hang their heads in shame.

Now, to Sand Amps and Current Capability. It is a well known fact that dualcons are current friendly, paper sensitivity figures notwithstanding.This is due to the unavoidably exacting 2nd order crossover, which is not the easiest of electrical loads. Trading quantity for quality however is a generally unwise gambit and dualcons are not shy about revealing grit and glare. Worst case scenario is represented by the previously denounced class AB 150+ watt Meridian (on the DMTs), which exhibited glassiness to rival the entire window surface of the Burj al Khalifa. On the other hand the most memorable sandamp pairing was obtained with the equally class AB 50 watt Nagra MSA, (on Yorks and Cants), a combo so good that it beat out my reference, 20 watt class A Pass Labs First Watt F5. It may also be noted that the Yorkminster-Quad 909 pairing was unimpeachably endearing, to the point of setting something of a record in the price-value sweepstakes. Quirkiest solid state combination (with the DMTs) was the obscure Ariston Amplifier, a Scottish OEM Nait wannabe, which substituted the cheap Naim volume pot with an even cheaper and nastier integrated chip. Not too bad really but inferior to Stan Curtis’ equally IC kneecapped Quad 77 integrated. Not recommended finally would be pairing the otherwise patient DMTs with the dependable Mission Cyrus 2. This supposedly safe combo produced bass mooing which would have done a herd of Angus cows proud. Even Tannoys get the blues sometimes.

R. Pamphonic 3000.

In my experience Tube Push Pull is the default configuration for dualcons. I’ve had this architecture in anything from giant 845 transmitting triodes to midget ECL 82s, along with pentode, beam tetrode and strapped triode combinations, with results that have consistently achieved both current delivery and tone quality - with one noteworthy exception: I really do not recommend the extremely popular Leben 300 with the Cants. I own the 300XS version, expensively retubed with Blackburn Philips EL 84s, Blackburn Mullard ECC 83 and JAN 5751 drivers. The Leben is expressly designed to accommodate both the high gain ECC 83 and lower gain 5751 twin triodes, but exhibits notable transformer induced hum with both of them. This is due to a defective layout which I would ordinarily consider a deal breaker, were it not at least partially redeemed by an excellent build and a singularly captivating sound. The mains derived hum is nonetheless unbearable using the high gain Mullards and weaker, but still obnoxious, with the 5751. A pity really, but there it is. Quirkiest tube configuration was with my father’s late Fifties Pamphonic 3000 integrated (on DMTs, Edinburghs and Yorks). Not the last word in cone control but well provided with musical as well as sentimental value. Single Ended Triode setups are where the rubber meets the road when evaluating dualcon compatibility. Somewhat contradictorily, SET amps are designed for simplicity but discussion of their performance quickly gets complicated, so I’ll give you the short version first. Can you, should you use SETs on Cants? The answer is yes, but. And it’s the but part that needs some delving into. The issue here is performance vs.power. To put it bluntly, the lower the power the more immediate the result, but what you gain in sheer musical communication you lose on dynamic swings. My SETs are custom made to my specs by Tektron of Italy (disclosure: yes, I am friendly with them). I pigheadedly favored 2A3 and 45 DHTs driven by 6J5 single triodes (look Ma, no 300Bs). This means that on a good day I can get a whole watt out of the 45s, almost, and a whopping 2 watts out of the 2A3s. Leaving aside preamplifier and tube options, which could be extensively discussed elsewhere, this means that ideal results are content dependent on music played. Turning to boomer alliterations again, both acoustic Dylan classics and De Rore quintets easily approach perfection. Janis Joplin’s Pearl on the other hand, or my favorite Alessandrini version of Monteverdi’s Vespro are tremendously enjoyable, but while Janis’ voice is truly heartrending and the baroque violin passages almost unsettlingly moving, the rhythm section behind the voice has no propulsive strength, and the violin vaulted spaces are merely alluded to. You want those, you need my 20 watt 300B push pull Nagra amp. Volume is not the issue here - I can easily fill my 50+ sqm listening room with the 45s, nor are microdynamics, but macrodynamic contrasts are muted, and tube rolling is not that helpful. And the Missa Salisburgensis is really not a thing. This also begs any technical discussion of the ever varying effects of cetacean output impedances, even with dedicated 8 ohm tap only trannies. Listening to SETs is an (educated) ear‘s first proposition, and as such gladly accepted by the Canterburys. As to quirks I fondly remember my first elephant driving flea, a Tektron ultra minimalist 6EM7s desk amp which sold me on the whole custom SET concept (reported on 6moons). 

L. Tektron 2A3 amp.

Class D, or chip, amps are easily disposed of. I’ve used Trends Audio and Amazon ordered 60 bucks SMSL thingies to excellent effect, thus faithfully replicating Dr. John’s impressions (here). As far as I’m concerned, when budget considerations intrude, go for the Cants and click the SMSL 36 Pro for an apparently lopsided but actually very well reasoned allocation of funds. Always assuming audiophiles have any familiarity with reason, of course.

About Biamping now. Dualcons are excellently suited to this and I‘ve rigged twin Quad 909s horizontally on the Yorks and tried out an extreme horizontal setup on the Cants using 45 SET monoblocs on the highs and a SET 2A3 two chassis stereo on the lows. Also quite recently, to purge myself of this excess I’ve vertically amplified the 15 inchers with two SMSL 36 matchboxes. In all instances the effects were as expected, expanded soundstage and different, though not necessarily superior, bass articulation. A possible improvement then, but to my ear not worth the hassle and the danger of 16 plus cables lying around. Also, the larger soundstage may, or may not, have been paid for with a minute loss of immediacy.

All in all, less is more to my fusty 20th century taste. Lastly and leastly, the obligatory mention of cables. Though I generally biwire lately I have fallen into the habit of single wiring my antiquarian SETs with Belden 9497 as a philological tweak, this despite my having penned a few years ago (here) some pricelessly witty, if ever so tolerant, remarks on Dr. John’s predilection for the very same cable.  Must be a lesson for us all there. (Editor: LOL. It's so wonderful that because of that we actually became friends!).

2 comments:

  1. The link for belden 9497 review is broken

    ReplyDelete