[Willakan]

"Nice" is in inverted commas for a reason.

 
And yes, I know you were saying the Woo and the M^3 with OPA627s sounded the same. I was speculating based on potential crosstalk problems as to why the GS-1 sounded different. As nick_charles says, it still seems unlikely that it would be audible, but as I say, wild speculation abounds in the absence of measurements.

 

[xnor]

Quote:

Originally Posted by upstateguy /img/forum/go_quote.gif
 
Didn't somebody say that if it sounds good and measures bad, you've measured the wrong thing?

 
This statement only makes sense in situations where there's no established set of measurements.
But we have several measurements (frequency and phase response, THD, IMD, SNR, and so on) that can be used to assess the performance of audio gear like amps and DACs and even components like operational amplifiers.
 
Another way to reply to this is: I've measured the right thing but you fail to understand the results and therefore misinterpret them.
What I mean with this is that you have to know what levels of distortion, crosstalk, frequency response deviation from flat etc. are audible. If you don't, how do you define "measures bad"? Is -70 dB crosstalk bad, what about -40 dB? Just because the result can look bad on a graph doesn't mean the measurement is bad or that you can hear differences.
 
Regarding your M^3, what gain does it have? Ti aka amb advises against the OPA637 depending on the configuration.
And how did you proceed in matching the volume between amps?

 

[Mad Max]

 
Quote:

Just a question:  To achieve some coloration, why would rolling opamps, caps etc, be preferable to the much more predictible and controllable results of EQing?

 
Because I think equalizing sounds like crap.  It's worse than component rolling or switching headphones in my opinion, and I think component/headphone swapping is unpredictable only when you use stuff you've never used before.  I have not tried any hardware equalizers, however.  I just seems to throw a veil over the treble and parts if not all of the midrange and bass in addition to constricting and muddying up the soundstage - and that's without any attenuation going on at all, just having the EQ on.  I don't think I will ever like EQ for the time being.

 

[xnor]

Quote:

Because I think equalizing sounds like crap.

Yet you listen to heavily equalized music. If anything is crap then it's what you wrote.
 

 

[Willakan]

If equalising sounds like crap, you're either doing it wrong or have a godawful EQ. Try a decent 24-bit one - Electri-Q is the only name I can remember offhand. With something like the ipod's equaliser, there are tonnes of problems, which shouldn't exist with decent software EQs. If you immediately notice a degradation in sound with no attenuation or boosting at all, something has gone horribly, horribly wrong somewhere.
 
EDIT: Xnor was rather more to the point I see.
EDIT2: Regarding the M^3 and potential problems with opamps, I think we can safely assume the 637 was not used in a low-gain amp, as I think upstateguy's M^3s are professionally built (rockhopper audio).

 

[bigshot]

There's plenty of colored-sounding gear and plenty of people who love that.  In fact, isn't the more neutral equipment the minority in the market?

Coloration is fine. That's why God invented tone controls. But you don't want hard wired coloration in your sources. If you do that, you need to make sure that each and every one of your sources is colored the way you want it. It's much easier to have all neutral sources and apply your coloration after the preamp stage. That way, one setting colors everything the same.

And no, neutral sources are the vast majority in the market. If you look at the specs for sources, they all strive to have a flat response.

 

[Mad Max]

 
Quote:

Quote:

Yet you listen to heavily equalized music. If anything is crap then it's what you wrote.
 

It's not the same thing, the EQs we use versus what was used in the studio.
 

 

[khaos974]

Nothing prevents you from using the same EQs as the ones they use in studios, that's what I do.:rolleyes:

 

[bigshot]

That isn't how EQ works. It corrects for differences between systems. Everyone has different needs. The settings for one set of speakers and room are nothing like the proper settings for a different set of speakers and room.
 
EQ doesn't add coloration and "veils" it removes them.

 

[xnor]

Quote:

It's not the same thing, the EQs we use versus what was used in the studio.

 
Several mastering grade, super expensive, parametric EQs can be nulled with freeware EQs. What this means is that you can, in fact, achieve the same thing. This is not suprising if you know some digital signal processing basics. I've developed graphic as well as parametric EQs and there is no magic going on behind the scenes. It's all based on the same maths.
 
To not turn this into "all EQs sound the same": Yes, there are different transforms but the simplest one is used in most parametric EQs, some even use iterative methods. Yes, there are different types of filters like IIR and FIR. Yes, some EQs have a feature to oversample in order to make IIRs behave like their analogue counterparts near nyquist. And so on..
 
But all of this boils down to transfer functions for each filter which mathematically define how the input signal is related to the output signal. Y = H . X, where Y is the output, H the transfer function and X the input.
You can analyze any parametric or graphic EQ quite easily. You can record what the EQ is doing and look at the frequency and phase response of each filter. All of this is completely transparent if you know DSP. If you want to know more attend a course or read a book on the topic.
 
 
@bigshot: Yeah, but room correction is just one of many areas of application. You can color the sound to whatever you like with an EQ. In the wrong hands you can cause clipping or veil and ruin sound quality.
EQs are powerful tools. If you know what you're doing I'd argue that you can improve almost every playback system, no matter if you have speakers or headphones.

 

[upstateguy]

Quote:

"Nice" is in inverted commas for a reason.

 
And yes, I know you were saying the Woo and the M^3 with OPA627s sounded the same. I was speculating based on potential crosstalk problems as to why the GS-1 sounded different. As nick_charles says, it still seems unlikely that it would be audible, but as I say, wild speculation abounds in the absence of measurements.

I didn't notice the inverted commas, but I knew exactly what you meant when you used the word "nice".
 
Never the less, I'm not sure you should classify a device with a sound signature as "broken".  Many times, but not all the time, a sound signature can be an improvement and sound very good.
 
Take the 650s for example.  They have a bassy laid back sound signature, yet they are able to reproduce the sound of my piano more accurately than any of my other headphones, including my new T-1s.
 
I don't disagree with you and xnor and bigshot in the science of it, but if you've gone to meets with your favorite headphones and CDs, or a music containing thumb drive, you've noticed that as you plug into the various rigs, and play your music, they don't all sound the same.  At one meet one of the guys brought a portable DVD player with a rock concert DVD... we went around attaching the analog outputs (with permission of course) to many of the amps at the meet and listened with our own headphones.  I was surprised at the differences I heard and we were always able to agree after listening, that we had heard a different sound signature.
 
So what I'm saying is that although the science end of it sounds correct, the reality is different.
 
I also have a problem with restricting your (not you personally) sample to things that measure similarly and sound similarly, and saying that everything that doesn't is either "broken" or a "bad design".
 
Also, we have avoided answering this question:  Does the new 32 bit Sabre chip have more resolution than older chips, and if it does, is it audible?
 

 
Quote:

 
This statement only makes sense in situations where there's no established set of measurements.
But we have several measurements (frequency and phase response, THD, IMD, SNR, and so on) that can be used to assess the performance of audio gear like amps and DACs and even components like operational amplifiers.
 
Another way to reply to this is: I've measured the right thing but you fail to understand the results and therefore misinterpret them.
What I mean with this is that you have to know what levels of distortion, crosstalk, frequency response deviation from flat etc. are audible. If you don't, how do you define "measures bad"? Is -70 dB crosstalk bad, what about -40 dB? Just because the result can look bad on a graph doesn't mean the measurement is bad or that you can hear differences.
 
Regarding your M^3, what gain does it have? Ti aka amb advises against the OPA637 depending on the configuration.
And how did you proceed in matching the volume between amps?

gain of 11 on the 637 M^3.
 
See above.  I don't disagree with you guys about the science, but I've found that the reality doesn't necessarily echo the science.
 


Quote:

If equalising sounds like crap, you're either doing it wrong or have a godawful EQ. Try a decent 24-bit one - Electri-Q is the only name I can remember offhand. With something like the ipod's equaliser, there are tonnes of problems, which shouldn't exist with decent software EQs. If you immediately notice a degradation in sound with no attenuation or boosting at all, something has gone horribly, horribly wrong somewhere.
 
EDIT: Xnor was rather more to the point I see.
EDIT2: Regarding the M^3 and potential problems with opamps, I think we can safely assume the 637 was not used in a low-gain amp, as I think upstateguy's M^3s are professionally built (rockhopper audio).

+1 on Electri-Q
 
and regarding the M^3, you can't use a 637 in the ground channel at any gain.... you have to use the 627.
 


Quote:

 
Several mastering grade, super expensive, parametric EQs can be nulled with freeware EQs. What this means is that you can, in fact, achieve the same thing. This is not suprising if you know some digital signal processing basics. I've developed graphic as well as parametric EQs and there is no magic going on behind the scenes. It's all based on the same maths.
 
To not turn this into "all EQs sound the same": Yes, there are different transforms but the simplest one is used in most parametric EQs, some even use iterative methods. Yes, there are different types of filters like IIR and FIR. Yes, some EQs have a feature to oversample in order to make IIRs behave like their analogue counterparts near nyquist. And so on..
 
But all of this boils down to transfer functions for each filter which mathematically define how the input signal is related to the output signal. Y = H . X, where Y is the output, H the transfer function and X the input.
You can analyze any parametric or graphic EQ quite easily. You can record what the EQ is doing and look at the frequency and phase response of each filter. All of this is completely transparent if you know DSP. If you want to know more attend a course or read a book on the topic.
 
 
@bigshot: Yeah, but room correction is just one of many areas of application. You can color the sound to whatever you like with an EQ. In the wrong hands you can cause clipping or veil and ruin sound quality.
EQs are powerful tools. If you know what you're doing I'd argue that you can improve almost every playback system, no matter if you have speakers or headphones.

The deeper we delve into this, the more things don't sound the same.....
 
The science says they should, but going to meets and listening to rigs says they don't.  Sometimes its sound stage, other times is frequency response differences. like the difference between 880s and 650s and still other times it's resolution, where one Dac, Amp or entire Rig is "cleaner" and "clearer" than another. 
 
One would think that if all gear sounded "relatively" the same, all the rig combinations would also sound "relatively" the same.
 

 

[xnor]

Quote:

The deeper we delve into this, the more things don't sound the same.....
 
The science says they should, but going to meets and listening to rigs says they don't.  Sometimes its sound stage, other times is frequency response differences. like the difference between 880s and 650s and still other times it's resolution, where one Dac, Amp or entire Rig is "cleaner" and "clearer" than another. 
 
One would think that if all gear sounded "relatively" the same, all the rig combinations would also sound "relatively" the same.

Science does not say everything should sound the same. That's BS.
 
Imo, the biggest differences heard are due to different output impedances. After that comes frequency response issues of the DAC or amp (for example low freq. roll-off). After all, frequency response is probably the most important thing to our hearing.
 
Without doing precise level matching it is pretty much pointless to compare different rigs. I'd be surprised if you did not notice differences between any two rigs if the volume levels were not matched properly.
Does that make the rigs themselves sound different? Nope.
 
Ideally, you would match the volume, sit with your back facing the rigs and let a buddy switch (randomly) between them. Unless you've done something like that, how can you tell the differences you heard are real and unrelated to volume mismatch, looks etc.?

 

[Willakan]

Regarding sound signatures, the 650 is a transducer, not an amp or DAC - choosing headphones or speakers to colour the sound is OK I suppose.
Regarding "sound signatures" in equipment, I can't agree with you on that. Any hi-fi system should start from the assumption that the recording is perfect. Obviously, it isn't, but unless you assume that you end up compensating for deficiencies that may or may not exist. Hi-fi was meant to be the pursuit of perfect reproduction of the original recording, not audio SFX. If you DO want to alter the sound, why would you ever want to do that with differences inbuilt into the equipment, that cannot be disabled? 
 
I know about the restrictions on OPA637 usage in the M^3 - the thing about professional building was to say I never thought a professional builder would ship amps that went against the manufacturer's guidelines (having said that, still very unlikely if you self-built)
 
As to the giant differences heard at meets, there are lots and lots of suspects as to the differences. Sorry to bring it up again, but I really think people underestimate just how monstrously large the differences are that failure to volume match precisely can produce - combined with the human mind  even larger differences can result - if they didn't we wouldn't be human!
 
And that's assuming all the amps involved were by-the-numbers-designed SS amps, which seems somewhat unlikely at a head-fi meet.
 
I'm sorry to come back to a typical measurement-backer defense, but it's beginning to look like the most plausible explanation here. 
 

 

[Grahame]

^
That's not even mentioning Fletcher–Munson curves  (equal-loudness contours)  (remember "loudness" buttons)
 

 

[upstateguy]

Quote:

Science does not say everything should sound the same. That's BS.
 
Imo, the biggest differences heard are due to different output impedances. After that comes frequency response issues of the DAC or amp (for example low freq. roll-off). After all, frequency response is probably the most important thing to our hearing.
 
Without doing precise level matching it is pretty much pointless to compare different rigs. I'd be surprised if you did not notice differences between any two rigs if the volume levels were not matched properly.
Does that make the rigs themselves sound different? Nope.
 
Ideally, you would match the volume, sit with your back facing the rigs and let a buddy switch (randomly) between them. Unless you've done something like that, how can you tell the differences you heard are real and unrelated to volume mismatch, looks etc.?

As long as you agree that all complex devices or even most complex devices don't sound the same I'm satisfied.  It's not really important how or why. 
 
That Carver was able to produce and sell amps that historically sounded different, should really end this discussion of "sameness sounding".
 
I understand the level matching rhetoric and have been part of some DBTs.  I've even used those same arguments myself.  I agree with the science, not the reality.
 

 
Quote:

Regarding sound signatures, the 650 is a transducer, not an amp or DAC - choosing headphones or speakers to colour the sound is OK I suppose.
Regarding "sound signatures" in equipment, I can't agree with you on that. Any hi-fi system should start from the assumption that the recording is perfect. Obviously, it isn't, but unless you assume that you end up compensating for deficiencies that may or may not exist. Hi-fi was meant to be the pursuit of perfect reproduction of the original recording, not audio SFX. If you DO want to alter the sound, why would you ever want to do that with differences inbuilt into the equipment, that cannot be disabled? 
 
I know about the restrictions on OPA637 usage in the M^3 - the thing about professional building was to say I never thought a professional builder would ship amps that went against the manufacturer's guidelines (having said that, still very unlikely if you self-built)
 
As to the giant differences heard at meets, there are lots and lots of suspects as to the differences. Sorry to bring it up again, but I really think people underestimate just how monstrously large the differences are that failure to volume match precisely can produce - combined with the human mind  even larger differences can result - if they didn't we wouldn't be human!
 
And that's assuming all the amps involved were by-the-numbers-designed SS amps, which seems somewhat unlikely at a head-fi meet.
 
I'm sorry to come back to a typical measurement-backer defense, but it's beginning to look like the most plausible explanation here. 
 

 
 
I'm sorry to come back to a typical measurement-backer defense, but it's beginning to look like the most plausible explanation here.
See above
 
Hi-fi was meant to be the pursuit of perfect reproduction of the original recording, not audio SFX.
Is it the reproduction of the recording we're after or the reproduction of the event?  Perhaps some of the different sounding equipment does a better job at reproducing the event..........  besides, except maybe for audiophile masters, you know how lousy most recordings are engineered....   made to sound as good as possible through mediocre speakers, in untreated rooms.  How many times have you read something like "if it sounds good through these monitors (name your brand), it will sound good through anything."
 
....why would you ever want to do that with differences inbuilt into the equipment, that cannot be disabled?
Carver made a bundle doing it.  Apparently it is something that is desired, and to a large number of people it sounds better.
 
Again, I have no quarrel with any of the reasons you have brought up and have used them all at one time or another.  My issue is that complex devices with various components and topologies are not going to "all sound the same". 
 
If we can agree that some of these complex devices can be made to sound different and that some of those devices that can be made to sound different have been marketed, produced and sold (think Meridian and Carver and Wadia) the thread can be over.