IPB

Welcome Guest ( Log In | Register )

2 Pages V  < 1 2  
Reply to this topicStart new topic
Headphone amps, external power supplies: what difference do they make?, was: "First post here, Hi."
skamp
post May 12 2013, 10:21
Post #26





Group: Developer
Posts: 1450
Joined: 4-May 04
From: France
Member No.: 13875



QUOTE (db1989 @ May 12 2013, 03:17) *
Thanks for doing this so I donít have to. wink.gif


I blame head-fi prose for making me nauseous.

Of interest, is Ethan Winer's description of 4 parameters that affect sound quality: "noise, frequency response, distortion, and time-based errors.". Incidentally, those are measurable. I don't know if it has been done already, but I wonder if anyone's ever conducted a battery of double-blind tests to match their thresholds of audibility with measurements. That would be very interesting (though I can't be arsed to do it myself).


--------------------
See my profile for measurements, tools and recommendations.
Go to the top of the page
+Quote Post
Arnold B. Kruege...
post May 12 2013, 14:31
Post #27





Group: Members
Posts: 3923
Joined: 29-October 08
From: USA, 48236
Member No.: 61311



QUOTE (skamp @ May 12 2013, 05:21) *
QUOTE (db1989 @ May 12 2013, 03:17) *
Thanks for doing this so I donít have to. wink.gif


I blame head-fi prose for making me nauseous.

Of interest, is Ethan Winer's description of 4 parameters that affect sound quality: "noise, frequency response, distortion, and time-based errors.". Incidentally, those are measurable. I don't know if it has been done already, but I wonder if anyone's ever conducted a battery of double-blind tests to match their thresholds of audibility with measurements. That would be very interesting (though I can't be arsed to do it myself).


While Ethan's list lacks some rigor (the better words are IMO noise, nonlinear distortion, and linear distortion), the idea is very good.

The problem with testing the thresholds of hearing for those things is that things can get real complicated fast as soon as your tests engage things like masking.

Arguably the first well-known tests for such things resulted in the Fletcher Munson curves which are interesting because they were done in such as way as to pretty much avoid masking. The general rule is that since masking is so endemic, Fletcher and Munson's numbers are usually highly optimistic, IOW too sensitive. But they are indicative. Perceptual coders would have never worked out if we thought that Fletcher Munson were the be all and end all.

One thing that can be said is that if you get all forms of noise, nonlinear distortion, and linear distortion more than 100 dB down, you need to move on for sure.

The actual thresholds for specific things are mostly in the 30-60 dB range, depending. There are a few cases where 20 dB down can suffice.
Go to the top of the page
+Quote Post
psgarcha92
post May 12 2013, 20:55
Post #28





Group: Members
Posts: 5
Joined: 11-May 13
Member No.: 108067



Respected Moderators,
I am sorry that i did not read the TOS at all. Now that i have, i will be taking care of all that i have been notified about in the preceding posts and TOS.
Thanks for being patient.

@skamp,
Thanks for your replies. You guys are way more experienced about this stuff than i am, i will be taking extreme care of what i post here from now on.

@saratoga
In my reply to the OP, i thought i would just mention my Rig in-case he wonders. I wasn't asking him to use an amp, i just mentioned my Rig. My reply was about trying another set of Earphones and see how it goes for him. It was you who pointed out that an adding an amp makes zero sense. Which i found insulting, and that's why i replied to it. I happen to like the coloration that i end up with, nothing else. The post was about changing Headphones, not adding an amp. I am sorry if i offended you in any way.

Regards
Go to the top of the page
+Quote Post
saratoga
post May 12 2013, 22:36
Post #29





Group: Members
Posts: 5034
Joined: 2-September 02
Member No.: 3264



^^ unless something is really screwy with that amp you are not getting any coloration. That's my point, you took one good output and substituted it for another equivalent one. That doesn't do anything smile.gif. Then you posted to tell us about it.

I am not offended and I didn't mean to insult you but I was trying to suggest to you that you may not understand what you are doing and might want to read a bit more.
Go to the top of the page
+Quote Post
Arnold B. Kruege...
post May 13 2013, 17:33
Post #30





Group: Members
Posts: 3923
Joined: 29-October 08
From: USA, 48236
Member No.: 61311



QUOTE (DVDdoug @ Dec 6 2012, 22:05) *
I don't remember if there is +/- 12V on the PCI bus. I would assume so because they used to have +/-12V RS-232 ports on I/O cards, but I don't know for sure.


You don't need to remember, you just need to know where the spec can be found:

http://en.wikipedia.org/wiki/Conventional_PCI

Pins 1 and 2 of a conventional PCI slot are for + and - 12 volt power.
Go to the top of the page
+Quote Post
saratoga
post May 13 2013, 22:41
Post #31





Group: Members
Posts: 5034
Joined: 2-September 02
Member No.: 3264



Any sound card will use a regulated voltage anyway (or at least it'd better or its quality is going to suffer), so they can generate any voltage level they want from the usual 3.3v rail. This is very uncommon though because most headphones have moved towards lower impedance designs that are meant to be driven by relatively low voltages. Even modern high impedance headphones are actually of relatively moderate impedance by historical standards. Its fairly rare to see headphones that can be safely (for the users ears!) driven at 2 Vrms these days.
Go to the top of the page
+Quote Post
Klipspringer
post Jun 14 2013, 20:28
Post #32





Group: Members
Posts: 4
Joined: 14-June 13
Member No.: 108663



Hi Folks,

This is my first post and I'm very interested in this topic.

Would the previous discussion also be applicable to electrostatic amplifiers for headphones like Stax. That is, would any given electrostatic amplifier operating within normal parameters (i.e all the circuits running within spec) be able to adequately drive the transducer and produce sound from the transducer that would be indistinguishable from any other electrostatic amplifier.

Has anyone ever done a DBT on this or can anyone point me to some literature where this might have been attempted?

Aside for the different principles of operation, is there anything at all special about the amplification needs of these transducers that would distinguish them from the amplification needs of dynamic headphones?

I hope I've conveyed my question clearly and those who have researched Stax headphones can probably understand my curiosity!
Go to the top of the page
+Quote Post
saratoga
post Jun 14 2013, 20:47
Post #33





Group: Members
Posts: 5034
Joined: 2-September 02
Member No.: 3264



QUOTE (Klipspringer @ Jun 14 2013, 15:28) *
Would the previous discussion also be applicable to electrostatic amplifiers for headphones like Stax.


No, that is a radically different technology with no relationship to what has been discussed in this thread.

QUOTE (Klipspringer @ Jun 14 2013, 15:28) *
Aside for the different principles of operation, is there anything at all special about the amplification needs of these transducers that would distinguish them from the amplification needs of dynamic headphones?


Yes, they require an enormous drive voltage.
Go to the top of the page
+Quote Post
Klipspringer
post Jun 15 2013, 00:57
Post #34





Group: Members
Posts: 4
Joined: 14-June 13
Member No.: 108663



QUOTE (saratoga @ Jun 14 2013, 11:47) *
QUOTE (Klipspringer @ Jun 14 2013, 15:28) *
Would the previous discussion also be applicable to electrostatic amplifiers for headphones like Stax.


No, that is a radically different technology with no relationship to what has been discussed in this thread.

QUOTE (Klipspringer @ Jun 14 2013, 15:28) *
Aside for the different principles of operation, is there anything at all special about the amplification needs of these transducers that would distinguish them from the amplification needs of dynamic headphones?


Yes, they require an enormous drive voltage.


Thanks Saratoga for the reply. Yes I'm aware of the difference in technology. I'm curious though if an electrostatic amplifier has a sound profile that the transducer reflects, one that is obvious and could be easily identified in a DBT.

My understanding from reading is that a properly operating amplifier just amplifies a signal and thus should not impart much if any sonic change on the transducer. Also, I've made a little test between different amplifiers on my dynamic headphones and had difficulty telling any appreciable difference between say an iPod's amplification and more expensive amplifiers. This test wasn't controlled and was only level matched through hearing. Regardless, I couldn't really pick one for the other (I hope the previous statement doesn't violate a TOS!).

I ask because there are a wide variety of choices for electrostatic amplification ranging from a few hundred to a few thousand dollars. I would like to purchase some nice electrostatic headphones, but am hesitant to move forward because I cannot adequately evaluate the claims of others in regard to amplification.

If amplification of electrostatic headphones is indeed critical, then I must further examine the amplification element of this purchase. Otherwise, I'll just get the best transducer I can afford and something economical that swings an adequate amount of voltage to drive them.

Go to the top of the page
+Quote Post
Arnold B. Kruege...
post Jun 15 2013, 14:42
Post #35





Group: Members
Posts: 3923
Joined: 29-October 08
From: USA, 48236
Member No.: 61311



QUOTE (Klipspringer @ Jun 14 2013, 19:57) *
QUOTE (saratoga @ Jun 14 2013, 11:47) *
QUOTE (Klipspringer @ Jun 14 2013, 15:28) *
Would the previous discussion also be applicable to electrostatic amplifiers for headphones like Stax.


No, that is a radically different technology with no relationship to what has been discussed in this thread.

QUOTE (Klipspringer @ Jun 14 2013, 15:28) *
Aside for the different principles of operation, is there anything at all special about the amplification needs of these transducers that would distinguish them from the amplification needs of dynamic headphones?


Yes, they require an enormous drive voltage.


Thanks Saratoga for the reply. Yes I'm aware of the difference in technology. I'm curious though if an electrostatic amplifier has a sound profile that the transducer reflects, one that is obvious and could be easily identified in a DBT.


Hard to say since virtually every electrostatic headphone comes integrated with its own power amp. All things considered, that is probably how things should be.


QUOTE
My understanding from reading is that a properly operating amplifier just amplifies a signal and thus should not impart much if any sonic change on the transducer.


All true but that mostly relates to loudspeakers that are designed to work any good amplifier. I don't know of any electrostatic headphones that play by that rule book.

QUOTE
Also, I've made a little test between different amplifiers on my dynamic headphones and had difficulty telling any appreciable difference between say an iPod's amplification and more expensive amplifiers. This test wasn't controlled and was only level matched through hearing. Regardless, I couldn't really pick one for the other (I hope the previous statement doesn't violate a TOS!).


And if you make a reasonable extrapolation of that to electrostatic headphones?


QUOTE
I ask because there are a wide variety of choices for electrostatic amplification ranging from a few hundred to a few thousand dollars. I would like to purchase some nice electrostatic headphones, but am hesitant to move forward because I cannot adequately evaluate the claims of others in regard to amplification.


The wisdom I receive from sophisticated technicans with the resources to check this out is that electrostatic headphones have no inherent advantages over the best conventional headphones.


QUOTE
If amplification of electrostatic headphones is indeed critical, then I must further examine the amplification element of this purchase. Otherwise, I'll just get the best transducer I can afford and something economical that swings an adequate amount of voltage to drive them.


IME there are a number of very good alternatives in the top performance rungs of the ladder, but no clear overall winner.

A lot of money can be wasted chasing the one very best, while in fact any of several very good alternatives can be highly satisfying.
Go to the top of the page
+Quote Post
Klipspringer
post Jun 16 2013, 08:47
Post #36





Group: Members
Posts: 4
Joined: 14-June 13
Member No.: 108663



Thanks Arnold for the thorough reply. I can't really draw any conclusions from my little A/B test beween headphone amps that wouldn't violate a TOS, so I'll leave it at that!

I currently have a really nice dynamic headphone setup and was sort of wondering if the electrostatic world would be oodles better. Considering the additional amp purchase it might not be worth it.

If the sound profile was totally different (I was hoping someone who had a Stax setup would chime in here), then it might be worth it, but if your knowledgeable pals say these two technologies are similar for the most part, then maybe I'll pass for now and wait until I can actually demo a system.

I would still like to understand from a scientific perspective why one electrostatic amp would sound different than another on a given electrostatic headphone. I don't really understan why a little (headphone) transducer should be any different than a big (speaker) one where, from my reading, it's been clearly demonstrated that speaker amps don't impart a marked sonic signature if they're operating nominally.

Why would the headphone transducer be different?
Go to the top of the page
+Quote Post
Arnold B. Kruege...
post Jun 16 2013, 10:23
Post #37





Group: Members
Posts: 3923
Joined: 29-October 08
From: USA, 48236
Member No.: 61311



QUOTE (Klipspringer @ Jun 16 2013, 03:47) *
Thanks Arnold for the thorough reply. I can't really draw any conclusions from my little A/B test beween headphone amps that wouldn't violate a TOS, so I'll leave it at that!

I currently have a really nice dynamic headphone setup and was sort of wondering if the electrostatic world would be oodles better. Considering the additional amp purchase it might not be worth it.

If the sound profile was totally different (I was hoping someone who had a Stax setup would chime in here), then it might be worth it, but if your knowledgeable pals say these two technologies are similar for the most part, then maybe I'll pass for now and wait until I can actually demo a system.


I had a chance to A/B a Stax versus a Sennheiser set of headphones at a high end audio show some years back. Not scientific, but I'm not also not claiming any dramatic difference. They both sounded nice, but the Sennies were a lot more practical. As I mentioned a local acoustics research lab catering to the Auto business (I live in Detroit) did both listening and technical tests and found that they were a little different but that neither had a strong advantage over the other.

QUOTE
I would still like to understand from a scientific perspective why one electrostatic amp would sound different than another on a given electrostatic headphone.


There's not a lot to understand. Making amps sound different is very easy. We built audio power amps from the late 19-teens to the early-mid 1960s before they were good enough to start sounding a lot the same.

These days you almost have to go out of your way to build a power amp that sounds different, but of course you can still do it and people do it for good reasons by putting a DSP inside the amp.

QUOTE
I don't really understand why a little (headphone) transducer should be any different than a big (speaker) one where, from my reading, it's been clearly demonstrated that speaker amps don't impart a marked sonic signature if they're operating nominally.


If you look at on-axis response curves for some of the better speakers, they have flatter response than many headphones.


QUOTE
Why would the headphone transducer be different?


Because it bypasses the head and the pinnae.
Go to the top of the page
+Quote Post
Klipspringer
post Jun 16 2013, 18:54
Post #38





Group: Members
Posts: 4
Joined: 14-June 13
Member No.: 108663



QUOTE
There's not a lot to understand. Making amps sound different is very easy. We built audio power amps from the late 19-teens to the early-mid 1960s before they were good enough to start sounding a lot the same.

These days you almost have to go out of your way to build a power amp that sounds different, but of course you can still do it and people do it for good reasons by putting a DSP inside the amp.

OK, I get this. Would it be fair to suggest then that some boutique manufacturers are deliberately (well intentioned I'm sure) tweaking components that result in EQ stuff inside the amp to distinguish the sound from another amp?

Is that the sort of general thing going on with claims over at head-fi that amp A sounds so much more better than amp B?

QUOTE
Because it bypasses the head and the pinnae.

OK Right. So here we're talking about the perception of sound rather than physical size of a transducer. Also, I just read that headphones are specifically tweaked to emphasize and de-emphasize certain frequencies so as to enhance the illusion of space.

Thanks again Arnold it's all making a lot more sense to me now.
Go to the top of the page
+Quote Post
Arnold B. Kruege...
post Jun 17 2013, 12:32
Post #39





Group: Members
Posts: 3923
Joined: 29-October 08
From: USA, 48236
Member No.: 61311



QUOTE (Klipspringer @ Jun 16 2013, 13:54) *
QUOTE
There's not a lot to understand. Making amps sound different is very easy. We built audio power amps from the late 19-teens to the early-mid 1960s before they were good enough to start sounding a lot the same.

These days you almost have to go out of your way to build a power amp that sounds different, but of course you can still do it and people do it for good reasons by putting a DSP inside the amp.

OK, I get this. Would it be fair to suggest then that some boutique manufacturers are deliberately (well intentioned I'm sure) tweaking components that result in EQ stuff inside the amp to distinguish the sound from another amp?


I'm not a mind reader, nor am I able to test every amp made. I suspect that most amps with eq inside are made that way to optimize their use with specific speakers.

One exception is power amps that are intentionally made with ridiculously high source impedances. But then the results still aren't exactly what you say - they simply exaggerate the differences among different speakers.


QUOTE
Is that the sort of general thing going on with claims over at head-fi that amp A sounds so much more better than amp B?


Again I don't know for sure, but I suspect that many of the perceived differences reported at audiophile sites have a very simple cause - really badly done listening tests.

How many people actually level match and do quick switching under the control of the listener? IME do those two things and many people will start noticing that things that used to sound very different suddenly start sounding remarkably the same. They may probably still hear subtle differences until they go down the blind test/statistical analysis road, but many "mind blowing" differences are likely to go away.

I'm of the opinion that many sonic differences are in some sense real. The sense in which they are real is that in terms of what the listener hears with his ears, there are real differences. However the real differences are not due to inherent differences in the equipment, they are are due to uncontrolled influences in the listening evaluation.

QUOTE
QUOTE
Because it bypasses the head and the pinnae.

OK Right. So here we're talking about the perception of sound rather than physical size of a transducer. Also, I just read that headphones are specifically tweaked to emphasize and de-emphasize certain frequencies so as to enhance the illusion of space.


The methodology and criteria for spectral shaping of the response of headphones probably varies. I suspect that like speakers, it is done based on a combination of measured response and the opinions of one or more golden ears, whether in-house or a consultant.

One of the interesting set of factoids out there is the response of Sennheiser RS 160, 170, 180 and 220 family of wireless headphones.

http://www.headphone.com/rightbetweenyourears/?p=1132

I suspect that all 4 have the same basic drivers, but that the electronics packages vary. We know for sure that the 160 has a fairly wimpy and brain dead electronics package compared to all the rest. As the price goes up, they fix the notch and crank in more bass. Both are just too easy to do if you can control the electronics package. The 220 may have a driver with more Xmax or not.

This post has been edited by Arnold B. Krueger: Jun 17 2013, 12:57
Go to the top of the page
+Quote Post

2 Pages V  < 1 2
Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 



RSS Lo-Fi Version Time is now: 20th October 2014 - 10:49