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Mr Peabody
07-28-2008, 08:52 PM
My CD player is unique in that it has 2 analog filters to choose from. One the manual describes as having a very linear frequency response. This one makes the instruments sound like everything is shoulder to shoulder in a line across the sound stage. This is a similar trait my Krell players had. The benefit to this is sometimes subtle details are easier to hear because of the evenness, another, a more controlled bass sound. The second one has a less linear frequency response and I forget exactly how they describe it in the manual. When switching to this your hear the sound stage almost relax, a depth is perceived, instruments have more of a 3D image and more ambient information. I personally like the 2nd better. I'm sure not everyone after listening to the two would agree but it got me wondering if this difference could all be just frequency response and as we all talk about difference in gear, or lack there of, I really find it interesting that this type of difference can be made with just a filter. To me, this shows one account of how difference, can, be made. If you had two players of the same quality using the typical one filter application, brand A uses a linear filter, brand B uses one not so linear, then how can you deny a difference in sound? The two players may even look virtually identical on paper.

Thinking of synergy, how would a linear CDP effect a system not so linear? There could be varying preferences but I think most would find that synergy would happen best when a player has the same character as the system it's placed in.

Anyway I have been fascinated by this filter thing and thought I'd throw it out to inform and insight :)

kexodusc
07-29-2008, 04:15 AM
I'm sure not everyone after listening to the two would agree but it got me wondering if this difference could all be just frequency response and as we all talk about difference in gear, or lack there of, I really find it interesting that this type of difference can be made with just a filter.

Mr P, you bring up a few interesting questions - is linearity the goal? That all depends on what your CD player manufacturer considers "linear". If it means super flat response, then I would tend to agree with that as the goal for a few reasons, but ultimately they boil down to personal preference, not absolute correctness.

The sound characteristics you described are very similar to 2 pairs of small computer speakers I made. The first measured very flat in FR (+/-2 dB max), the second had a slightly recessed midrange and probably measured +3/-5 dB (going by memory here). Problem is they sounded better on my desk in a near field application. They definitely sounded a bit boomy/sizzly if I set them up in a typical stereo/triangle config, but also still a bit, well, more fluid, or easy. Soundstage depth and separation of instruments varied greatly just by me moving. (Behold the power room acoustics - IMHO equal or greater in importance than any single piece of gear). So, I guess my personal preference won out over convention cause I preferred the speaker that didn't measure as tight in FR.

To me the differences you described are directly attributable to FR. And in my head manufacturers should pick linearity as a starting point. After all, it is the job of the recording engineer to capture any soundstage depth etc, and that's accounted for in the frequency gains on the recording. If we deviate from linearity, well, we're not hearing what the engineers wanted us to hear, or what was going on in a live recording...

...but, who's to say the engineers have it right? Who's to say the equipment used faithfully captured the FR profile of the music that night? Who's to say we are wrong because we prefer altering the FR profile of the music we listen to because it sounds better to us? (we all have different hearing abilities).

I'm not terribly familiar with how filters are applied on your CD player, but I'm guessing it slants the response in favor of what the designer prefers - which is not at all unlike what amplifier and speaker designers do. If everything measured perfectly flat, everything would sound very similar. But that's not the case. And good thing too, our hearing responses are all too different for a one size fits all solution. And it is likely that variance in our sensitivities to certain frequencies that contributes to our preferences for different equipment.



To me, this shows one account of how difference, can, be made. If you had two players of the same quality using the typical one filter application, brand A uses a linear filter, brand B uses one not so linear, then how can you deny a difference in sound? The two players may even look virtually identical on paper. For sure.


Thinking of synergy, how would a linear CDP effect a system not so linear? There could be varying preferences but I think most would find that synergy would happen best when a player has the same character as the system it's placed in. Well, if it was linear, it would be "neutral" to the system components around it, would it not? We start to climb a slippery slope if we buy bright speakers, then a warm amp to counter excessive brightness, etc. If I bought a highly detailed amp/pre-amp, and very detailed speakers, then a CD player that focused on providing great airy detail, well it might be too much of a good thing by the end?

Think this just further demonstrates the importance of synergy.

Ajani
07-29-2008, 03:23 PM
My CD player is unique in that it has 2 analog filters to choose from. One the manual describes as having a very linear frequency response. This one makes the instruments sound like everything is shoulder to shoulder in a line across the sound stage. This is a similar trait my Krell players had. The benefit to this is sometimes subtle details are easier to hear because of the evenness, another, a more controlled bass sound. The second one has a less linear frequency response and I forget exactly how they describe it in the manual. When switching to this your hear the sound stage almost relax, a depth is perceived, instruments have more of a 3D image and more ambient information. I personally like the 2nd better. I'm sure not everyone after listening to the two would agree but it got me wondering if this difference could all be just frequency response and as we all talk about difference in gear, or lack there of, I really find it interesting that this type of difference can be made with just a filter. To me, this shows one account of how difference, can, be made. If you had two players of the same quality using the typical one filter application, brand A uses a linear filter, brand B uses one not so linear, then how can you deny a difference in sound? The two players may even look virtually identical on paper.

Thinking of synergy, how would a linear CDP effect a system not so linear? There could be varying preferences but I think most would find that synergy would happen best when a player has the same character as the system it's placed in.

Anyway I have been fascinated by this filter thing and thought I'd throw it out to inform and insight :)

I think the answer is No... If we all really wanted linearity, we'd simply select the products with the best measurements and be done with it... You'd probably stick with Krell or Arcam over Conrad Johnson (since I suspect those 2 measure better)...

Not to be an anti-audiophile, but the very fact that all Brands don't sound the same, or even remotely close, tends to indicate that linearity is not the goal... Brands are voiced to appeal to the needs of specific listeners... Planars are not designed to appeal to the same consumers as Horn or traditional driver speakers... B&W has a definite 'house sound' as does Monitor Audio, Dynaudio, PSB, Klipsch and Revel... each aimed at consumers with different preferences in sound... This is why brand bashing makes absolutely no sense... What sounds good to me, may sound like rubbish to you and vice versa...

bobsticks
07-29-2008, 04:12 PM
...but, who's to say the engineers have it right? Who's to say the equipment used faithfully captured the FR profile of the music that night? Who's to say we are wrong because we prefer altering the FR profile of the music we listen to because it sounds better to us? (we all have different hearing abilities).


Ain't nobody sayin' a thing because you're right. I've known a few amateur soundmen in the bar/club scene who's hearing is so shot that their gigs are painful. I'm sure this is not an anomaly within the industry.

Besides, it's my house.




...Planars are not designed to appeal to the same consumers as Horn or traditional driver speakers... B&W has a definite 'house sound' as does Monitor Audio, Dynaudio, PSB, Klipsch and Revel... each aimed at consumers with different preferences in sound... This is why brand bashing makes absolutely no sense... What sounds good to me, may sound like rubbish to you and vice versa...

Yup, so when I'm done with this current set of toys I'll get a new one. Despite declarations to the contrary this is a great time to be an enthusiast. So many fantastic companies producing topnotch kit. So many tunes, so little time...

Mr Peabody
07-29-2008, 06:50 PM
The filter I was talking about is more accurately a oversampling algorithm. The second is described as not being so linear but balances it with greater dynamic range and liveliness. Aw, here read it for yourself it will probably make more sense: http://www.taelektroakustik.de/eng/index.htm

I know this is deeper than I need go but I wonder just how linear a live performance is? I think a live acoustic set would sound more like the 2nd algorithm because the performers would be in different positions on a stage where maybe a live show using amps or PA system may be more like the first filter in a way, forgo venue influence, the amps would make more of an even sound stage and dynamics may be limited by the electronics used.

O'Shag
07-29-2008, 07:13 PM
Mr. P, what Transparent cables are you using? I think ultimately it's whatever sounds better for you that counts. My own preference would definitely be for a more 3-dimensional presentation. It would seem that would be the more realistic. A flat 2-D image really doesn't do it for me, even if there is more apparent detail. That Boobs n Bum CD player must sound really good nudge nudge wink wink say no more:wink5: .

Mr Peabody
07-29-2008, 07:47 PM
My Transparent is all in my HT set up and I can't remember the series but it's only a notch or so above the entry level. I do have a long pair that connects my phono stage to my preamp. I use the Siltech New Yorker in my stereo (CJ) rig.

kexodusc
07-30-2008, 05:41 AM
The filter I was talking about is more accurately a oversampling algorithm. The second is described as not being so linear but balances it with greater dynamic range and liveliness. Aw, here read it for yourself it will probably make more sense: http://www.taelektroakustik.de/eng/index.htm.
Like I said, depends how the filters actually work. Their descriptions are rather vague, but I don't like the steep roll-off they suggest in Filter 1. Sounds a bit like signal shaping/changing rather than playback. The 2nd filter sounds less aggressive, but there's not enough info.


I know this is deeper than I need go but I wonder just how linear a live performance is? I think a live acoustic set would sound more like the 2nd algorithm because the performers would be in different positions on a stage where maybe a live show using amps or PA system may be more like the first filter in a way, forgo venue influence, the amps would make more of an even sound stage and dynamics may be limited by the electronics used

How linear is the live performance? It's not really applicable. The live performance is the original, true signal. It isn't linear (or there'd be no dynamics and all frequencies would sound as loud), but it is what we are trying to reproduce perfectly. If a component doesn't have a perfect FR linearity, it alters the relative magnitude of some of the instruments and notes from what they truly should be. Ie, if a bass note on stage was -4 dB relative to the singer's voice, and a CD player plays it back at -7 dB, we've altered the signal from what was true. In theory, the recording preserves the truth, and linearity faithfully plays it back as it should be.

But, it's not that simple. If the perfect linearity comes at the expense of faithful and perfect reproduction of the dynamic range, then we can see a similar phenomenon. A cymbal transient might be +14 dB higher than that same singer's voice, but now it's beyond the ability of the CD player to capture. Is it clipped and how hard? We're losing some of the musical info by way of detail and spacial cues - which sounds exactly like what you might be describing here?

I would experiement with both - I bet for typical rock/blues music, with comparatively limited dynamic range, Filter 1 might be better - but for jazz and classical I'd probably lean to Filter 2.

A bit of FR deviation isn't the end of the world as your environment will introduce way more deviation. And a bit of dynamic range loss isn't the end of the world either - I bet your listening room has a lower noise floor than most full concert halls so more info is getting to your ears anyway, also a lot of factors influence how much decay a sound wave will experience, and dynamic range isn't always the limiting factor.

It's nice to be able to customize to match your listening.

Mr Peabody
07-30-2008, 06:29 PM
The first filter don't sound rolled or cut off though. The high end seems not to have much difference in magnitude between the two.

So you are saying if a recording has a frequency response all over the place then a linear player will play it as it is, "all over the place"? I'm not so sure it works that way. On my Krell 280cd I could definitely hear a difference in a good and bad recording but the presentation was almost always similar, if that makes sense.

Your guess on the filters is exactly what I thought too. I find myself using 2 the most. I really don't enjoy when everything sounds like it's on the same line, it just don't seem natural.

kexodusc
07-31-2008, 05:49 AM
The first filter don't sound rolled or cut off though. The high end seems not to have much difference in magnitude between the two.
Not surprised, I don't think the steep roll-off occurs in the standard fundamental audible range (20Hz-20KHz)
I won't pretend to be an expert on upsampling anything or digital filters, but based on the tiny blurb I read, I can speculate they start to aggressively roll-off well above the 10 KHz threshold, so you aren't noticing rolled off highs, but might be noticing a slight lack of transients and spatial cues that give music it's "3 D" body. I don't know how else they could do it without doing something too drastic. I doubt the steep roll-off is all that adverse anyway. There's a point where we can't even hear transient information. My guess is it allows the device to focus it's limited attention to the frequencies you can hear, thus ensuring linearity.



So you are saying if a recording has a frequency response all over the place then a linear player will play it as it is, "all over the place"?
Well, if the FR of the device is perfectly linear, then it won't change the magnitude of the frequencies captured in the recording. It'll play those frequencies back at the exact level it's reading them off the recording. If the recording says bass is -4dB relative to the vocals, it won't change that relative difference in volume. In theory we'd hope that the -4 dB bass was the goal of the artist (the recording is capturing the artists desires) If it does change that relative difference, it's no longer perfectly linear.
Think about it. If you were to record a signal that was a frequency sweep from 20 Hz to 20 KHz at a constant gain and put it in the CD player, a perfectly linear cd player would always playback every frequency at the exact same level. IE it would be the reference level (+/- 0db). The closer to to a straight line the FR plot is with the sweep the more linear it is. No deviation or distortion of the original signal.

Obviously FR isn't everything in sound quality though. An $8 CD player is probably 99% as linear as an $8000 CD player these days. But I'm not aware of even the craziest science-loving objectivist that would suggest an $8 CD player sounds the same as an $8000 player, so the differences are coming somewhere else...but that's another thread.


I'm not so sure it works that way. On my Krell 280cd I could definitely hear a difference in a good and bad recording but the presentation was almost always similar, if that makes sense.

I think the Krell you mentioned is further example. Every CD player worth buying is pretty darn linear to start. How much excessively linear they get is the question. You're Krell distinguished between good and bad recordings because it didn't alter the relative FR much (it didn't try to "fix" bad recordings)- it preserved the crappy recording's info. The presentation would be similar because any distortion of the original signal that was occuring by design or otherwise would always happen in the same manner. Ie, if the Krell rolled off highs, it would apply that to all recordings. If it compressed dynamic range in the bass area, it would do that to all recordings. That's the great thing about machines. They're usually consistent. So their presentation is similar.



Your guess on the filters is exactly what I thought too. I find myself using 2 the most. I really don't enjoy when everything sounds like it's on the same line, it just don't seem natural.
Hmmm, I could be very, very wrong on my interpretation of the word "linear". I equate "linear' with FR in the context T+A uses it. You seem to be equating it with soundstage depth (everything in a straight line). I don't deny that's what you're hearing, but when I read their blurb on Filter 1:
"The first process (Filter 1) delivers an extremely linear frequency response "
they seem to suggest linear relates to the frequency response, the not the position of instruments on stage.

But if you're hearing Filter 1 put the instruments in the same line on stage, then I might be able to guess why...As I mentioned earlier - if the transients and spacial cues are being slightly sacrificed by the device in order to provide superior FR accuracy, then I think that's why you'd notice soundstage differences. Remember, these digital processing devices can only do so much work in a given second - so it chooses to focus on FR, or focus on Dynamics and other aspects. To perform one task as best it can, it has to dedicate more effort there and pay less attention to somewhere else. If Filter 2 isn't as anal about absolutely perfect FR, and is more concerned with transients and spacial cues, then it probably sounds a bit more 3-D and "natural", even if the FR isn't perfect (though I doubt the FR deviances are noticeable). Depending on the type of music, the need for one focus might outweight the need for another. It's a great feature to be able to customize, and maximize performance of the D/A converter by matching its tasks to the needs of the source.

To each their own. I personally feel too many stat-jockeys worry about watts, THD and FR when judging audio quality. I'm sure everyone's heard gear that measures great, but doesn't sound all that impressive...

Wish I could find one of those out my way...I'd love to play with it.

Mr Peabody
07-31-2008, 06:26 PM
I with you on linear, I was just talking about the perceived effect filter one has to me.

kexodusc
08-01-2008, 03:48 AM
I'm gonna have to keep an eye out for this player in stores. I don't recall seeing one.
Mr. P, feel free to experiment with different music types on each filter, I'm curious to know if less dynamic music comes through better on filter one for example?

Mr Peabody
08-01-2008, 05:39 PM
T+A has a lot of products, for sure keep your eye out I'd love to hear some one else's opinion of them. I personally have not heard anything bad or even average from them, it's all been great. When I get a chance I want to go in and hear the Power Plant integrated which is my players mate. I wanted to hear it last visit but ran out of time with all the experimenting we did.

I put my Krell in the system to see how it would sound. Man, the bass and power is incredible. For just kicking back and listening though I still prefer the CJ but miss that power. While the Krell was in, I dropped the new Disturbed in. Now that disc sounded better with filter 1. Odd thing, when I played this disc through my Adcom rig it didn't sound clean. I was playing it loud. So I thought the Krell would rock and it did but the recording still wasn't clean. So I guess it's one of those things you were talking about being in the master. You know what I mean, of course with Rock and distortion clean probably isn't the right word, more like the distortion is more and tries to mask some of the other things.