Dynaco Stereo 70 II power amplifier Manufacturer's Comment
Editor: My response to Corey's incompetent review of the Stereo 70/II should be just that—a letter to Corey:
Point/Counterpoint: Corey. You incredibly misguided wordmeister. If, as you say, you want to find the best-sounding affordable tube gear, the new Stereo 70/II should have lit your fire. After all, every major audiophile publication in the world has rated the ST-70 as a great value, with The Abso!ute Sound concluding that its "clarity and detail are nothing less than stunning."
First of all, using a ProAc Response Two with a sensitivity of 86dB and a minimum power rating of 50W is a mismatch. A speaker with at least 90dB efficiency must be used to audition the Stereo 70/II. Next, what the hell is an Aunt Corey's Passive Preamp doing in a so-called high-end critic's system? I've never seen it rated by any publication, including Stereophile, and doubt whether it can drive the ST-70 to full output. I've heard all about your room, with its slap-back echo and compressor noise, so enough is wrong with your setup to invalidate your opinion altogether. Now, let's look at your critique.
Regarding the use of bandwidth-limiting filters: This is known in the biz as "prior art," and neither Van Alstine nor Dynaco can claim that it is an original concept. In any case, we are not old enough to be geezers, and name-calling is just another way for you to distract your readers with your gonzo bull. Putting the circuit board on top as you say for easy access, also allows dirt, dust, and humidity to attack the board. We use a much larger circuit board than any of your modifier friends, with tube sockets PC-board$nmounted to eliminate one sonic variable, the wiring placement. Further, the circuit board on the new ST-70 is under the chassis to shield the circuitry from both electrical interference and tube heat radiation. It is fully protected from the environment by a removable metal cover for service or modkateers. It is obvious you just won't let go of the past, and that brings us to the next rub.
No audio dealer in the US or anywhere else carries the old Stereo 70. Consumers cannot go into any store we know of and compare the old vs the new, but since you insist on comparing the two, I must point out that reviewers the world over have covered that topic already. There is simply no comparison. The Stereo 70 Series II outperforms the original in every area of performance, and that is, again, old news. Tom Norton of Stereophile pointed out in his review of the Genesis IM-5200 Vol.14 No.10, p.172 that the new Stereo 70 outperformed the Audio Research Classic 120s in the bass, treble, imaging, and depth categories, but doubted if a passive preamp could drive the ST-70/II adequately. Ken Kessler also raved about the bass and treble improvement in the new 70 in his report in Hi-Fi News & Record Review in April. Since we are already the best-selling 35W stereo tube amp in the world again, consumers have written to tell us as well how the new 70 is the best-sounding amp they found at any price. So what are we to believe? That you are right and the rest of the world is wrong?
Comparing the new 70 to a $5000 pair of VTLs is also ludicrous. Although we admire and respect the VTL, within the 1 to 30W range, there is just not $4000 worth of difference. In fact, I challenge you to a blind test wherein we can A/B compare the two systems. If you want to be credible again, you will take up the challenge. Although I have been invited to resubmit the Stereo 70/II for another review by your publisher, we at Dynaco have invested too much time, effort, and money to let you or any of your other associates play fast and loose with our reputation. Your personally biased approach is an insult to your readers and manufacturers alike, and serves no useful purpose. This time you picked on the best-loved brand of all time. And we say, enough is enough.
Your conclusion that we sound better than most of the sub-$1000 solid-state "dreck" out there is contradicted in the very next paragraph. Get it straight. Which "dreck" are you talking about? Which other gear don't we keep pace with? Name names if you dare, or was this just more of your typical BS? You clearly have no idea what materials, labor, and overhead costs of manufacturing are in the US today, or you would know why the new 70 is such an achievement. There are no other tube amps at $995 selling in stores. It is, in fact, the greatest amp for the money, and that's why it is the best seller in its category. You take yourself way too seriously, and you do the readers of Stereophile a great disservice with your misinformation. I'm not the first manufacturer to make this claim, but I hope I'm the last.
We at Dynaco abhor the lack of professionalism you employ to reach your conclusions, and know without a doubt that your review was written to generate controversy and thus sell more magazines. It is pathetic that you have to resort to this kind of tabloid journalism to make a living.—Bob Rapoport, Dynaco
P.S. After reading your latest article ("As We See It," Vol.15 No.7), it is obvious to all that your methodology is flawed. Your catharsis shows your immaturity as a reviewer and further erodes your credibility. Thanks for putting your foot in your mouth before our review came out!
To the publisher and editor of Stereophile:
As with any product, the Stereo 70/II has its flaws and its virtues. All we expect from any publication is a fair, unbiased, and thorough approach. Virtually every other critic has used a few different speakers with the new 70 to find its strengths and weaknesses, whereas Corey only used a speaker which is too inefficient to be driven by a 35W amp. He made no attempt to explain this limitation in his review, which most other professional audio critics would have done. I suppose if he had written a rave review, we would not be writing this kind of letter. But I must say, the impact of your reviews on people's lives is profound, and for that reason, you should be mindful of doing a good job.
We believe in free speech and know your readers are intelligent enough to take what you write with a grain of salt. We now join a growing number of manufacturers who will not submit products to you for evaluation. We are not afraid of the truth, as evidenced by our willingness to submit our products to any publication interested in reviewing them. Our experience with Stereophile has been marked by a feeling that we are not part of your "clique," and this has troubled us the most.
We have made a sincere effort to bring back a great American brand. To make improvements in the original designs, build them with pride in the USA, and keep the high-value reputation for which we are known, our primary concern.—Bob Rapoport, Dynaco
Regarding the specific points made by the obviously angry Mr. Rapoport—he would be wise to read Robert Deutsch's article elsewhere in this issue—I am satisfied that there is no mismatch between the ProAc Response 2's sensitivity and the power output of the revised Stereo 70. Indeed, I feel that the kind modulus of impedance of the ProAc makes it a prime candidate for use with tube amplifiers of limited current delivery, such as the Nobis and Dynaco models. Indeed, this whole mismatch idea is a red herring. Bob Rapoport told me during a telephone conversation on July 22 that he strongly recommends the Celestion SL600Si for use with the Stereo 70/II, a loudspeaker at least 4dB less sensitive than the ProAc. Ken Kessler even used the 6dB less-sensitive LS3/5a in his evaluation.
Regarding Mr. Rapoport's comments on the quality of Corey's listening environment, these are misinformed hearsay from, I was told by Mr. Rapoport, Scientific Fidelity's Michael Maloney (whose Tesla speaker, of course, last April received less than favorable reviews from a number of the magazine's writers, including Corey). In fact, I have spent some time listening to music in the room Mr. Maloney apparently described to Mr. Rapoport, and am convinced that it suffered from neither slap echo nor "compressor noise" [presumably from the refrigerator in the kitchen]. In any case, CG moved before undertaking this amplifier review, and will describe his new room in a forthcoming "Matter of Taste" article.
And if readers would care to re-read TJN's review of the Genesis IM-5200, they will see that his doubts about passive preamplifiers were general, not specific to the Stereo 70/II, and are actually not relevant to this discussion, Corey's preamp having an active output stage. (Having auditioned Corey's preamp, I am confident that it is suitable for use as a reviewing tool.) Tom's preference for the Dynaco over the Audio Research amplifier was also specifically meant in the context of the Genesis speakers, which have a rather up-tilted balance. I suspect that the Dynaco's deliberate treble-response tailoring was a strong factor here.
Regarding Corey's reference in the review to the sound of an original but refurbished Stereo 70, I felt at the time the review was commissioned—and still feel—that this is a fair comparison due to the large population of original amplifiers still out there and still obtainable used from specialist sources. Although Larry Archibald and Tom Norton discussed further coverage of the sound of the Stereo 70/II in the magazine's pages in telephone conversations with Mr. Rapoport, this was as a result of Mr. Rapoport informing them that he believed Stereophile reports included comment from multiple reviewers and that he wished this had been the case with this review. In fact, as regular readers will be aware, this is not standard Stereophile procedure, though it is at The Abso!ute Sound.
At Stereophile, I do organize further coverage when the outcome of a review is controversial, as was the case with the EAD DSP-7000 also reviewed in this issue. Although LA points out that he made no such offer to Bob Rapoport, I did mention this policy to Bob in our aforementioned telephone conversation. However, on behalf of Panor, Mr. Rapoport declined any further coverage in Stereophile, both in respect to Dynaco products and to products that Panor distributes, such as the Acoustic Energy loudspeakers.
On a more general point, I work hard to ensure that this magazine's value judgments and sonic descriptions are both correct and not the result of bias. There is also no "clique" of manufacturers whose products we recommend. I am saddened, therefore, by Mr. Rapoport's flailing around to find any reason—other than the Stereo 70/II's sound quality—to explain CG's value judgments. Are we wrong and the "rest of the world" right? Personally, I don't find it surprising that an amplifier with a deliberate bass rolloff was found by my reviewer to sound lean. I was also saddened to read the following letter, which was faxed to Stereophile's East Coast advertising representative, Ken Nelson, the day after I had what I thought was a civilized telephone conversation with Mr. Rapoport. For the record, reviews in this magazine are fair, thorough, correct, and unbiased; threats of withdrawal of advertising have no influence on the publication of a review.—John Atkinson
To Ken Nelson, Nelson & Associates
Dear Ken, much to my dismay, the owner of Panor Corp., Dynaco's parent company, has ordered that we cancel our ad program with Stereophile magazine. I argued on behalf of keeping our ads going, saying that it would serve no useful purpose, and perhaps would make us look bad, but he would not hear of it. His argument is that any publication that publishes a review that is unfair, not thorough, and biased, is not going to receive any support from Panor now or in the future.
My rebuttal to Corey’s review says it all. This is all very unfortunate. If you can do anything on your end to stop this review from being published until a fair or more professional article can be written, it would help diffuse this situation.
I spoke to JA yesterday in an attempt to reason with him, but he was an asshole to me on the phone. As expected, he defended Corey.
I can tell you from my conversations with dealers and reps over the last week, that Corey’s latest ranting and raving over which music to use to evaluate systems has had a very negative response. Oh sure, some of the readers in his age range will agree, but us boomers think it is just a further lowering of the standards Stereophile used to represent.—Bob Rapoport, Dynaco.