How could any dedicated tuber resist this fine $3K Meixing Mind Da push-pull 5x70wpc channel KT-90 AV amp?
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Also doubles as a 500W space heater!
How could any dedicated tuber resist this fine $3K Meixing Mind Da push-pull 5x70wpc channel KT-90 AV amp?
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This sentence confuses me, are you granting that this preamp does make gobs of 3rd and/or second harmonic distortion?However Amir may regard tube preamps and power amps in general, even those designed this well, generating gobs of 3rd and/or second harmonic distortion, consider this situation: My friend Pierre designed and built these high efficiency horn speakers; see posts 15, 266, 15, 276.
I'm extremely familiar with the Aikido preamps (John Broskie is an old friend of mine) and have built, used, and published some measurements on them. They actually do not have "gobs" of 2nd and 3rd harmonic, the design is a reasonably good one with distortion and noise being below the level where human ears are likely detect it. So they end up sounding no different than any other reasonably good preamp. He documents the builds well and sells very nice PCBs to ease the construction.Has Amir ever reviewed AND listened to a well designed and built tube preamp? Especially one making the best use of the 6SN7 tube?
And by listening I mean using it to drive both his favorite power amp and speakers.
If Amir would grant the audio community only one such review I'd hope it would be Roy Mottram's Aikido SP14, with the resistor and cap upgrades. http://www.tubes4hifi.com/SP14.htm
However Amir may regard tube preamps and power amps in general, even those designed this well, generating gobs of 3rd and/or second harmonic distortion, consider this situation: My friend Pierre designed and built these high efficiency horn speakers; see posts 15, 266, 15, 276.
Beyond the Ariel
Hi Lynn Olson, thank you for the explanation in your post. If I understand correctly your other posts, you plan to use a passive cross-over. Should its resistance not be added to that of the output resistance of the amplifier and the conductors? I think that apart from that, I have all the...www.diyaudio.com
Pierre also designed and built an all solid-state MOSFET power amp to drive these speakers. I believe that at one time he drove the power amp with a solid state line stage, but was less than impressed with the sound. Then he built his own version of John Broskie's Aikido line stage and revision.
I don't know if Amir or anyone here have reviewed any of Broskie's Glassware line stages, but Pierre does nothing but rave about all aspects of sound quality with this tube line stage driving his system. But he raves even hotter about the Don Sachs DS2 preamp I acquired last month. Recall here where Don loved the sound of the SP14 so much that he designed his own version/ http://www.tubes4hifi.com/SP14.htm
Note that the SP14 is available as a kit or assembled.
Pierre's DAC https://www.audiosciencereview.com/...may-probably-the-best-discrete-r2r-dac.10161/
But what's probably most important to consider is this: As Amir says during the first 60 secondss of this great tutorial, nothing determines the degree of sound quality more than the speakers. And in addition to high resolution TAD 15" woofers, Pierre's two-way passively crossed speakers use the Radian 745neoBe beryllium compression drivers.
https://www.usspeaker.com/radian 745neoBepb-1.htm Like electrostatic speakers, beryllium drivers are probably the least tolerant of poorly mastered recordings, system noise, less than excellent frequency odd-harmonic distortion products than any other kind of diaphragm material. And yet Pierre reports basking in sonic heaven from SACDs and high quality vinyl largely due to this 6SN7 tube preamp, and which he may have built for less than $1000. in parts.
Thanks to Amir's videos I have certainly gained a far better understanding of several important audio measurement concepts and, the procedures for doing-or at least observing and evaluating-these measurements in the most practical ways.
I am equally grateful for when some of those classic myths are dispelled during these sessions.
But as is often with his DAC and other hardware reviews, Amir further validates his findings by doing extensive listening tests. And so I await his review of either
or http://www.tubes4hifi.com/SP14.htm
I made this admission assuming that Amir's likely well aware that even the best designed tube amps and preamps typically produce far more measurable distortion than solid state ones. But given their immense popularity among audiophile and DIY audio community, is that alone a reason not to review and run listening tests on them? Had I Amir's know-how, time and hardware I'd certainly be too curious not to want put something like the SP14 on the test bench and run listening session to find out what all the fuss is about.This sentence confuses me, are you granting that this preamp does make gobs of 3rd and/or second harmonic distortion?
If so why would you desire such a review? The measurements would only support your claims and no matter what the speaker, the listeners preference would guide his reaction to the added distortion of it's sound.
I'm extremely familiar with the Aikido preamps (John Broskie is an old friend of mine) and have built, used, and published some measurements on them. They actually do not have "gobs" of 2nd and 3rd harmonic, the design is a reasonably good one with distortion and noise being below the level where human ears are likely detect it. So they end up sounding no different than any other reasonably good preamp. He documents the builds well and sells very nice PCBs to ease the construction.
But the idea that they have any kind of "sound" is ludicrous. If you want to make that claim, it only has validity if you have done listening tests with proper controls (ears only).
Would you said that grovegardner's posts 35, 37, 38 offer among the best descriptions of the Aikido?But the idea that they have any kind of "sound" is ludicrous. If you want to make that claim, it only has validity if you have done listening tests with proper controls (ears only).
But the idea that they have any kind of "sound" is ludicrous. If you want to make that claim, it only has validity if you have done listening tests with proper controls (ears only)
Would you said that grovegardner's posts 35, 37, 38 offer among the best descriptions of the Aikido?
https://www.diyaudio.com/community/...or-less-than-great-sounding-cds.408331/page-2
No. It reads like nonsense.Would you said that grovegardner's posts 35, 37, 38 offer among the best descriptions of the Aikido?
https://www.diyaudio.com/community/...or-less-than-great-sounding-cds.408331/page-2
Controls meaning, for example, comparative listening tests with otherwise well designed commercial and DIY solid state and/or tube amps?Did you read of any proper controls? I didn't.
No. Controls means ears only. No peeking. Double blind. Matched levels. If you can hear it without peeking, you can hear it.Controls meaning, for example, comparative listening tests with otherwise well designed commercial and DIY solid state and/or tube amps?
No, I would think that what BDWoody means by control is a known reference. For example, an amplifier which has been both measured AND ear tested-and then doing the exact same two things to the device under examination. I think the unspoken issue here is that if an amplifier is merely presumed to have relatively higher distortion of any kind and/or less than ruler flat frequency response, than what is deemed a credible reference amplifier, then it is automatically disqualified from being investigated any further-and that the disqualification is held further justifiable simply because subjective judgements, like comparative listening tests are virtually worthless at least if quantitative signal measurements are not carried out. Sadly, this is presumably why, to the best of my knowledge, Amir has yet to conduct reviews on any tube amps or tube line stages.No. Controls means ears only. No peeking. Double blind. Matched levels. If you can hear it without peeking, you can hear it.
When peeking is eliminated, electronics with reasonably low noise/distortion and flat frequency response generally cannot be distinguished by sound.
No, I would think that what BDWoody means by control is a known reference.
Sadly, this is presumably why, to the best of my knowledge, Amir has yet to conduct reviews on any tube amps or tube line stages.
…and ANY valid sonic claim must have those basic controls. Without that, human brains (all human brains!) find all sorts of differences that aren’t real. Ears are truthful, brains are liars.No, I would think that what BDWoody means by control is a known reference. For example, an amplifier which has been both measured AND ear tested-and then doing the exact same two things to the device under examination. I think the unspoken issue here is that if an amplifier is merely presumed to have relatively higher distortion of any kind and/or less than ruler flat frequency response, than what is deemed a credible reference amplifier, then it is automatically disqualified from being investigated any further-and that the disqualification is held further justifiable simply because subjective judgements, like comparative listening tests are virtually worthless at least if quantitative signal measurements are not carried out. Sadly, this is presumably why, to the best of my knowledge, Amir has yet to conduct reviews on any tube amps or tube line stages.
Indeed, if you're talking about eliminating the risk of bias from both the witness and the researcher-such as during forensic testing https://en.wikipedia.org/wiki/Blinded_experiment#In_forensics -then I totally agree. Example? Amir has one or two assistants who alternately feed the same signal to reference amplifier X and test amplifier…and ANY valid sonic claim must have those basic controls. Without that, human brains (all human brains!) find all sorts of differences that aren’t real. Ears are truthful, brains are liars.
Ears only. That’s the key to validity.
Not just forensics-any sensory testing. I wrote a simple overview of this a few years back (it’s been well known in sensory science for more than a century) and Amir has posted a video outlining controlled methods of doing listening tests.Indeed, if you're talking about eliminating the risk of bias from both the witness and the researcher-such as during forensic testing https://en.wikipedia.org/wiki/Blinded_experiment#In_forensics -then I totally agree. Example? Amir has one or two assistants who alternately feed the same signal to reference amplifier X and test amplifier
Y to Amir's headphones. Amir does not know beforehand or at any point during the listening tests which amp is which, and can therefore only rely on his ears to judge the
sound quality between the X and Y amps.
That in itself is quite an accomplishment for a tube preamp like this.Do those controls and you’ll find that the Aikido sounds no different than any other decent preamp, tube or otherwise.
Not so much. The only issue tube preamps often have is driving low impedances; other than that, for the small voltage swings needed, the designs are easy. You have to do something really special to screw them up, and even tube preamps from the 50s and 60s can perform quite well.That in itself is quite an accomplishment for a tube preamp like this.