22 July, 2011

Overview: Wavac Part II - PR-T1 MD-805 MD-811

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Overview: Wavac Part II
Review: Wavac PR-T1, MD-805 and MD-811

Wavac Overview Part I

Belatedly, here is Part II of my Wavac experience. To pick up where we left off in Part I, after Danz heard my Wavac combo, he decided to acquire a set. I loaned him my set but he continued to source for Wavac on the internet. In a surprisingly short time, Danz made the decision to go for the higher models. The MD-805 monoblocks were sourced from the UK and these arrived in HK while I was in NYC. Then Danz found a set of PR-T1 in New Jersey. Not quite knowing how impossibly heavy these are I volunteered to take these back for him so he can save on the considerable delivery charges. So the seller dropped them off in NYC and I was surprised (to say the least) by the very heavy weight (69 lbs) of the 3-piece PR-T1. However, the compensation was that I got to play with this beauty for more than 1 month in NYC before I got back.

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Work of Art: PR-T1

In contrast to my more humble PR-X2, you can actually find some user comments and even review for this flagship preamp (enjoythemusic). Most certainly a work of art, aesthetically I'd say it is likely the most beautiful preamp I have seen.

I did not open up the power supply, only the main chassis. Although both use 2x 12AU7 per channel, If you compare it to the innards of the PR-X2 (in Part I) you shall notice that while the amplification circuit boards are quite similar the PR-T1 is distinguished by: 1) the presence of 2 large output transformers; 2) presence of 4 input transformers; and 3) a high-precision stepped volume pot. With all these transformers, the PR-T1 easily provides balanced XLR inputs and output, in addition to the RCA provisions.

In my month with the PR-T1 I used only the RCA output. As for inputs I used mostly RCA but I did try out the XLR in with my AQVOX phonoamp (reviewed here). As with my PR-X2, this is a high-gain design (favored by SET amp designers) and the gain pots proved useful in attenuation, although in this case of stepped resistor volume pot non-linearity at low volume settings is not a concern. The sound was wonderful with almost everything I threw at it: phenomenally detailed, with great presence and dynamics, a dark background and great tonal allure. There was not even a hint of frequency roll-off at extremes (that can plague designs using lesser transformers). This is one in the top echelon.

Odd man out: MD-811
Before proceeding to the magnificent MD-805 monoblocks, let me take a detour. I feel almost guilty, but for the sake of narrating my experience with Wavac, this has to be.

This discontinued MD-811 was relatively affordable ($4000) a decade back, and there were quite a few useful reviews (enjoythemusic; positive-feedback; and most unlikely HomeTheaterReview). 811(A) is a transmitting tube, cheap and readily available. But the design of Wavac was certainly not compromised. Despite its relatively low cost, it is largely of the similar design as the current MD-300B, employing the company's trademark interstage transformers. The following circuit is likely an earlier one, using 6F6 rather than the later 6Y6, but you get the idea:

By chance I spotted one on Audiogon while I was in NYC, and took delivery from a very nice gentleman before arrival of the PR-T1. The unit was in very good shape, and came with extra valves. Basically, aside from the power tube, it uses the same tubes as the MD-300B, a pair of 12AU7 and a pair of 6Y6.

Turning on the amp there was a sense of deja-vu. Its very quietness mirrors the 300B based amp, and it ran for long periods with stability. But it was also immediately apparent that the tonal balance is significantly different. Although the MD-811 has a beautifully refined treble, the MD-300B amp seemingly has more air on top. I was not sure whether there was some loss of detail compared with 300B (few tubes can match up in this regard) but after extended listening I think it is just apparently so. The MD-811 has excellent detail retrieval, but its much fuller bass, of the character that Dick Olsher (a very good reviewer usually) wrote about in enjoythemusic (see above link) tilts the tonal balance to make the treble seem a trifle subdued. .

As rolling tubes did not change much the character of the amp, loudspeaker and ancillary matching became more of a concern. My YL horns have 15" woofers and a full bass. I did not have my MD-300B on hand, but when I switched in my Elekit 8300 300B amp the bass was more controlled.

Herein lies the surprise: contrary to usual expectations, the MD-811 did not match well with the PR-T1. Admittedly, one is a flagship product and the other entry level; still, one would expect more synergy from the same company, such as I experienced with the PR-X2/MD-300B combo. With the PR-T1 switched in, bass was most certainly over-ripe. The MD-811 matched better with a leaner preamp, such as Elekit's TU-875. There, you see, because of this I was a little uncertain of the nature of the PR-T1 until I came back to HK.

Enter the Dragon: MD-805
One day, after yumcha, JCR33 and I went to hear Danz' setup, a little stressful for me, and you shall see why.

We only used Danz' MD-805B monoblocks, but started the session with MY PR-X2 preamp. I was instantly amazed by the physical beauty and awesomely clean power of the MD-805. Basically it held the Tannoy Canterbury in a visor-like grip and would not let go. To make a comparison, subjectively I think it is quite a bit more powerful than the Unison Research Smart 845, Airtight 211 and Kondo Ongaku I have heard. I doubt with even less than 90 db loudspeakers they shall be found wanting.

Switching in the PR-T1 was a humbling experience. Immediately everything became more fleshed out and smoother at the edges. At Danz' place, clearly the PR-X2 was leaner and even a little edgy, something not apparent at my place. As a whole, the sweeping power and commanding authority of the PR-T1/MD-805 combo was unassailable, so much so that the picky Kondo guru JCR33 nodded in approval. I can only console myself with the thought that in terms of detail, treble air and bass contour the more expensive setup (newly installed) has perhaps not necessarily yet (for my taste) completely over-taken my similar Wavac setup, which has been in place for much longer. With time, I look forward to the time when this system completely trounces mine.


  1. hi
    Just found this and wanted to ask some questions. I am currently using a Cary 300sei integrated, which sounds lovely. I have a chance to get a Wavac MD-811, which has had the power caps re-done....and wondered if you feel there will be a significant difference in sound? I love how the Wavac looks but of course the md-811 is quite a bit older than the Cary and this also concerns me...thanks for your thoughts?

  2. I know the Cary 300SEI well. It is one of their better efforts. But I think the Wavac MD-811 is likely a superior amp overall.

    It depends on what you want. If you play complex music (classical or rock rather than simple jazz and vocals) and need power, the MD-811 should be SIGNIFICANTLY superior. It should also have better transient than the Cary. Tonally, it would be difficult to say. The 300B is leaner, which makes it seem to have a bit more air on top, but the MD-811 is no slouch here. I consume a large diet or orchestral music and there is no question the Wavac is for me.

    The MD-811 has NO caps in the signal path, so your unit's cap changes are probably in the power supply, which is usually a good thing! Make sure it is well done and good parts are used. Make sure you do not spend too much.

    The MD-811 has stayed in my system for a long time. I don't even change amps except to "review" them. Regarding the bass mentioned in this Overview Part II, it is no longer a problem after the Wavac PRT-1 is gone. Somehow, that flagship preamp has a heavy character that I don't quite like, as described in Part III (http://cheaptubeaudio.blogspot.hk/2011/10/yumcha-diaries-24-10-11-tannoy-wavac.html). I have to revise this Part II, and write a Part IV to "vindicate" the MD-811.

  3. Hello DrJohn, thank you for your nice website about tube audio. I am curious as to the Wavac MD-811 which you still use. I use JM Reynaud Offrande speakers, a 90dB/1W/m monitor. The 15W SET would probably be enough for them and a nice, more powerful alternative to 2A3 or 300B. A very practical question, do you know if this amplifier can be easily changed from 110-120V to 220-230V? It would increase my chances of finding one if I could also look beyond my European voltage on the worldwide market.

    Thank you,
    The Netherlands

    1. Hi August: The MD-811 should serve the JMR well. Unfortunately, I think the Wavac's do not have double windings for 110/220. I have seen them several times on the second-hand market, so be patient! :-)