I posted this in another thread, but I think it deserves to be read more widely. I recently stumbled across this long interview with Roger Sanders, an independent manufacturer of electrostatic speakers.
I had briefly heard of him before, but when reading the interview it dawned on me that he seems to be one of the few independent manufacturs who is deeply committed to rationality and objectivity when designing speakers. He makes a number of claims in the interview, and I would like to know more about the validity of those claims.
Challenge to y'all: I will list what I think are the most interesting claims he makes in the interview. Then I will ask you to indicate whether you agree or not - yes (Y), no (N), don't know (DK). And possibly motivate why. I will start myself to get the discussion going. Please read the interview first though!
1) "Roger Sanders makes the best loudspeakers in the world".
(DK - not listened to them or seen enough measurements, but Robert E. Greene in TAS seems to agree)
2) "A S.O.T.A. speaker must use an electrostatic midrange".
The reason he provides: "The reason that electrostatic speakers are so good is that they are the only type of midrange driver that has essentially no moving mass. Magnetic speakers simply cannot match the performance of electrostatics in the midrange because they are heavy so cannot be accelerated quickly and accurately at treble frequencies"
(DK - tbh I haven't listened enough to good electrostatic speakers. Are there measurements that back up this claim about electrostats vs magnetic speakers in general?)
3) "Magnetic woofers have many problems with their enclosures that cause them to produce with a lot of overshoot and ringing that makes it impossible for them to integrate well with a massless electrostatic speaker".
(N - I am skeptical of this claim. But are there measurements which can back it up? In general, my sense is that bass "quickness" has more to do with the room than with the woofers themselves)
4) "The solution is to use a transmission line enclosure system to virtually eliminate overshoot and ringing in the woofer".
(DK - I don't know enough about transmission lines, but I seem to remember that they have problems with time smear and phase behavior?)
5) "No speaker can be considered S.O.T.A. if it uses a passive crossover. All speakers will perform better when driven by active crossovers and individual amplifiers for each of their drivers".
(Y)
6) "Loudspeakers are the most important component in your system. All are seriously flawed. You should put most of your money and effort into getting the best ones you can".
(Y)
7) "Rooms interact with loudspeakers to seriously degrade the sound. It is essential to deal with this problem using proper positioning, room treatment, and DSP".
(N - I'm of the opinion that we "listen through" the room to a substantial degree, at least provided good speakers and good positioning. I think this position has more support in the peer-reviewed studies than Sanders' view)
8) "The distortion from a Class A amplifier is no lower than in a Class AB amplifier. So there is absolutely no reason to use Class A anymore"
(Y)
9) "I do not consider switch mode (Class D) amplifiers to be high fidelity devices". (for full bandwith)
Reason: "This is because they do not have linear frequency response. Their high frequency response depends on the character of the load (the loudspeaker). Therefore they must be specifically adjusted to your specific speaker to have linear frequency response. Because woofers do not reproduce high frequencies, switch mode amps are excellent for driving woofers (which require a lot of power)".
(DK - but my subjective listening inclines me to agree. When trying out class D myself it have sounded a bit artificial to my ears, but I have heard tailor-made active speakers (like the LS1) with class D which have sounded excellent. Are there any independent measurements on this?)
10) "Digital recording media [and digital playback] is flawless. By comparison, analog is very poor".
(Y)
11) "As long as you use a data rate of 192 KBPS or higher, you cannot hear any difference between an MP3 recording and the original source".
(Y - with reservations. I know there are people who have been able to ABX 192 KBPS vs higher resolution, but I think it's virtually indistinguishable for normal listening to music. There might be an argument for using full 16-bit if one does heavy DSP and EQ to the signal though)
12) "DSP systems are extremely powerful and effective tools. They can improve all audio systems and every audiophile should use them".
[Sanders uses it for crossover and speaker eq, and recommends room correction in the bass but not in higher frequencies]
(Y)
13) "There is no such thing as too much power"
Reason: "It is easy to show that most speaker systems require about 500 watts to play musical peaks cleanly. Most audiophiles use amps with far less power. Therefore audiophiles are comparing clipping amps most of the time".
(Y - my gut agrees with this. But I would like to see more measurements on this, using the method he proposes with an oscilloscope)
14) "Components that meet the Basic Quality Criteria (BQC) for high fidelity sound always sound identical to each other".
He mentions this as the basic quality criteria: "1) Inaudible noise levels (a S/N of 86 dB or better is required), 2) Inaudible wow and flutter (less than 0.01%) 3) Linear frequency response across the audio bandwidth (20 Hz - 20 KHz +/- 0.1 dB), 4) Harmonic distortion of less than 1%"
(Y)
15) "You must do ABX testing to obtain valid results from listening tests".
(DK - I am not sure about his favoring of ABX over AB tests, and I'm not sure whether quick blind testing is able to reveal things like dynamic differences. But I agree of course that controlled blind listening is more valid than subjective sighted listening, if properly done, with subjects who are trained for the testing format)
-------
There is more in interview, but these were the claims which struck me the most. What do you guys think?
I had briefly heard of him before, but when reading the interview it dawned on me that he seems to be one of the few independent manufacturs who is deeply committed to rationality and objectivity when designing speakers. He makes a number of claims in the interview, and I would like to know more about the validity of those claims.
Challenge to y'all: I will list what I think are the most interesting claims he makes in the interview. Then I will ask you to indicate whether you agree or not - yes (Y), no (N), don't know (DK). And possibly motivate why. I will start myself to get the discussion going. Please read the interview first though!
1) "Roger Sanders makes the best loudspeakers in the world".
(DK - not listened to them or seen enough measurements, but Robert E. Greene in TAS seems to agree)
2) "A S.O.T.A. speaker must use an electrostatic midrange".
The reason he provides: "The reason that electrostatic speakers are so good is that they are the only type of midrange driver that has essentially no moving mass. Magnetic speakers simply cannot match the performance of electrostatics in the midrange because they are heavy so cannot be accelerated quickly and accurately at treble frequencies"
(DK - tbh I haven't listened enough to good electrostatic speakers. Are there measurements that back up this claim about electrostats vs magnetic speakers in general?)
3) "Magnetic woofers have many problems with their enclosures that cause them to produce with a lot of overshoot and ringing that makes it impossible for them to integrate well with a massless electrostatic speaker".
(N - I am skeptical of this claim. But are there measurements which can back it up? In general, my sense is that bass "quickness" has more to do with the room than with the woofers themselves)
4) "The solution is to use a transmission line enclosure system to virtually eliminate overshoot and ringing in the woofer".
(DK - I don't know enough about transmission lines, but I seem to remember that they have problems with time smear and phase behavior?)
5) "No speaker can be considered S.O.T.A. if it uses a passive crossover. All speakers will perform better when driven by active crossovers and individual amplifiers for each of their drivers".
(Y)
6) "Loudspeakers are the most important component in your system. All are seriously flawed. You should put most of your money and effort into getting the best ones you can".
(Y)
7) "Rooms interact with loudspeakers to seriously degrade the sound. It is essential to deal with this problem using proper positioning, room treatment, and DSP".
(N - I'm of the opinion that we "listen through" the room to a substantial degree, at least provided good speakers and good positioning. I think this position has more support in the peer-reviewed studies than Sanders' view)
8) "The distortion from a Class A amplifier is no lower than in a Class AB amplifier. So there is absolutely no reason to use Class A anymore"
(Y)
9) "I do not consider switch mode (Class D) amplifiers to be high fidelity devices". (for full bandwith)
Reason: "This is because they do not have linear frequency response. Their high frequency response depends on the character of the load (the loudspeaker). Therefore they must be specifically adjusted to your specific speaker to have linear frequency response. Because woofers do not reproduce high frequencies, switch mode amps are excellent for driving woofers (which require a lot of power)".
(DK - but my subjective listening inclines me to agree. When trying out class D myself it have sounded a bit artificial to my ears, but I have heard tailor-made active speakers (like the LS1) with class D which have sounded excellent. Are there any independent measurements on this?)
10) "Digital recording media [and digital playback] is flawless. By comparison, analog is very poor".
(Y)
11) "As long as you use a data rate of 192 KBPS or higher, you cannot hear any difference between an MP3 recording and the original source".
(Y - with reservations. I know there are people who have been able to ABX 192 KBPS vs higher resolution, but I think it's virtually indistinguishable for normal listening to music. There might be an argument for using full 16-bit if one does heavy DSP and EQ to the signal though)
12) "DSP systems are extremely powerful and effective tools. They can improve all audio systems and every audiophile should use them".
[Sanders uses it for crossover and speaker eq, and recommends room correction in the bass but not in higher frequencies]
(Y)
13) "There is no such thing as too much power"
Reason: "It is easy to show that most speaker systems require about 500 watts to play musical peaks cleanly. Most audiophiles use amps with far less power. Therefore audiophiles are comparing clipping amps most of the time".
(Y - my gut agrees with this. But I would like to see more measurements on this, using the method he proposes with an oscilloscope)
14) "Components that meet the Basic Quality Criteria (BQC) for high fidelity sound always sound identical to each other".
He mentions this as the basic quality criteria: "1) Inaudible noise levels (a S/N of 86 dB or better is required), 2) Inaudible wow and flutter (less than 0.01%) 3) Linear frequency response across the audio bandwidth (20 Hz - 20 KHz +/- 0.1 dB), 4) Harmonic distortion of less than 1%"
(Y)
15) "You must do ABX testing to obtain valid results from listening tests".
(DK - I am not sure about his favoring of ABX over AB tests, and I'm not sure whether quick blind testing is able to reveal things like dynamic differences. But I agree of course that controlled blind listening is more valid than subjective sighted listening, if properly done, with subjects who are trained for the testing format)
-------
There is more in interview, but these were the claims which struck me the most. What do you guys think?
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