[seacard]

Does a certain amp match up better to a certain headphone, or is the headphone completely irrelevant so long as the amp has low output impedance, high input impedance, low distortion, and a flat frequency chart?

I am looking for an amp to match up with the Senn HD800. Is something cheap-ish like the Behringer HA4700 going to be just as good as anything else, or is there something that the Behringer can't do. If it's the latter, what spec should I look for to make sure that I wring everything out of the HD800.

 

[Uncle Erik]

It's a tough call with the HD-800. So far, we've only had thm for a couple of months and no consensus has been arrived at. There probably won't be an absolute consensus, either, but it'll be much better known by the end of the year.

One important factor to keep in mind is that the HD-800 is terribly amp sensitive. You will hear variations between amps. So far, I've been very pleased with their sound from transformer coupled tube amps. However, keep in mind that I'm a tubehead and really enjoy that sound. It's a little on the warm and tubey side, and that flavor comes through.

If you like a crisper sound, then solid state will give that to you. But since the HD-800 has amazing detail retrieval and is sensitive to amps, I'd go with something with a very clean, overbuilt power supply. Any flaws in amplification will show up with the HD-800.

 

[moonboy403]

Quote:

Originally Posted by seacard /img/forum/go_quote.gif Does a certain amp match up better to a certain headphone, or is the headphone completely irrelevant so long as the amp has low output impedance, high input impedance, low distortion, and a flat frequency chart? I am looking for an amp to match up with the Senn HD800. Is something cheap-ish like the Behringer HA4700 going to be just as good as anything else, or is there something that the Behringer can't do. If it's the latter, what spec should I look for to make sure that I wring everything out of the HD800.

Given that you were at the meet, I'm surprised you asked this question.

There were plenty of amps to audition and the most notable ones when you were present were Rudistor RPX-100, Zana Deux, Sonett, Apache, Hat Peed thingee with caps, Phoenix, and B22.

 

[johnwmclean]

Source is just as important as the amp. I've had a terrible time with the HD800's until just recently. My amp is considered a good match for the HD800, upon upgrading the source there has been a vast improvement. The HD800's are bitch of phone in a bad matched set-up.

 

[royalcrown]

Looking at the Behringer HA4700 you mentioned, I don't see why it should be a problem. It's likely that distribution amps like the HA4700 would be powerful enough to permanently destroy any headphone if cranked up all the way. Plus it has an impressively low output impedance for a professional amp, and while I haven't yet seen compelling proof that damping factor for headphones is as important as for speakers, the HD800 is the one to be safe about, given its lack of testing and high price. The HA4700 will provide plenty of power with inaudible amounts of distortion.

 

[seacard]

Quote:

Originally Posted by moonboy403 /img/forum/go_quote.gif Given that you were at the meet, I'm surprised you asked this question. There were plenty of amps to audition and the most notable ones when you were present were Rudistor RPX-100, Zana Deux, Sonett, Apache, Hat Peed thingee with caps, Phoenix, and B22.

Being a long-time reader of the Audio Critic, I'm sort of torn. I *think* I hear differences between solid state amps, but I also have never blind-tested them or volume matched. Peter Aczel's theory that all properly designed solid-state amps sound identical also makes good sense to me. I am too much of a science guy at heart (neuropsych major).

 

[Bullseye]

I think that behringer amp is a good option. Loads of features, nice price, nice specs.

 

[jcx]

Quote:

Originally Posted by seacard /img/forum/go_quote.gif Being a long-time reader of the Audio Critic, I'm sort of torn. I *think* I hear differences between solid state amps, but I also have never blind-tested them or volume matched. Peter Aczel's theory that all properly designed solid-state amps sound identical also makes good sense to me. I am too much of a science guy at heart (neuropsych major).

I think that could be a little bit beyond the evidence - some headphone impedances and amp combinations would be expected to show frequency response differences above ABX DBT thresholds ( tube amp high output Z or undersized output coupling Cap on SS portables ) - plus some (often recommended) combinations can fail the no clipping/current limiting preconditions at real world SPL when music dynamic peaks of +20 dB are considered

the more complete statement would be that practically all SS amps could be equalized and output impedance padded to sound the same (or even to sound like a tube amp)

diyAudio Forums - Blind Listening Tests & Amplifiers - Page 22

original article:

Stereophile: The Carver Challenge

 

[krmathis]

I believe that matching amplifier and headphone is important.
Lets say the headphone is on the bright side, then you probably do not want to pair it with an amplifier with the same bright sound signature. You may be better off with an amplifier that tone down the bright sound signature a bit, to make it all balanced.

Most headphones and amplifier have different sound signature and they need (imo) to be matched carefully.

 

[moonboy403]

Quote:

Originally Posted by seacard /img/forum/go_quote.gif Being a long-time reader of the Audio Critic, I'm sort of torn. I *think* I hear differences between solid state amps, but I also have never blind-tested them or volume matched. Peter Aczel's theory that all properly designed solid-state amps sound identical also makes good sense to me. I am too much of a science guy at heart (neuropsych major).

You should've been there toward the end of the meet when me, Deadneddz, and Santacore were auditioning the ALO Amphora, that little bugger was bright as hell with the D7000 when we turned it up and none of us could listen to it for anymore than 30 seconds where as it never happened on the Phoenix even though we cranked it up. If all solid state amps sound the same, that wouldn't have happened. Now do we really need to do a blind test to tell us that the unbearable ear-screeching brightness of the Amphora was caused by placebo?

 

[PhilS]

Quote:

Originally Posted by moonboy403 /img/forum/go_quote.gif Now do we really need to do a blind test to tell us that the unbearable ear-screeching brightness of the Amphora was caused by placebo?

Yes, only if the screechiness caused you to hurl could it be said not to be placebo, and perhaps not even then, as placebo is the most powerful force in the universe. Which makes one wonder, why don't they have a super-hero (or super-villian) named "Placebo- Man."

 

[seacard]

Quote:

Originally Posted by moonboy403 /img/forum/go_quote.gif You should've been there toward the end of the meet when me, Deadneddz, and Santacore were auditioning the ALO Amphora, that little bugger was bright as hell with the D7000 when we turned it up and none of us could listen to it for anymore than 30 seconds where as it never happened on the Phoenix even though we cranked it up. If all solid state amps sound the same, that wouldn't have happened. Now do we really need to do a blind test to tell us that the unbearable ear-screeching brightness of the Amphora was caused by placebo?

Well, there are really two parts to my answer. First, nobody claims that all amps sound the same, only that all properly designed amps sound the same. (I don't know myself if this is true, but let's at least get the theory right before we attack it.) I don't think it's worth spending a lot of time discussing ALO's merits as a company or a designer of high-quality equipment, but I haven't seen the input impedance, output impedance, voltage swing, distortion, or frequency chart. If I had to guess, the Amphora is not going to look very good on these numbers, and will probably look substantially worse than the $100 Behringer.

Second, you really may need to do blind testing. There is a great experiment where subjects were shown two lines. One line was clearly (and I mean CLEARLY) longer than another. But when others (confederates of the researcher) said that the lines were of equal length, the subjects of the experiment also agreed that the lines were of equal length. There is a lot of power in having somebody say "hey, this amp doesn't sound very good, take a listen and tell me what you think." Not saying that's what happened here (in fact, I'm fairly confident that the problem here was caused by a poorly-designed amp), but something to be taken into account.

 

[royalcrown]

Quote:

Originally Posted by moonboy403 /img/forum/go_quote.gif You should've been there toward the end of the meet when me, Deadneddz, and Santacore were auditioning the ALO Amphora, that little bugger was bright as hell with the D7000 when we turned it up and none of us could listen to it for anymore than 30 seconds where as it never happened on the Phoenix even though we cranked it up. If all solid state amps sound the same, that wouldn't have happened. Now do we really need to do a blind test to tell us that the unbearable ear-screeching brightness of the Amphora was caused by placebo?

There's an obvious explanation: the ALO Amphora runs off of a 9V battery. There have been measurements that show 9 volts is just not enough for some headphones:

Is a headphone amp needed? - Hydrogenaudio Forums

Clipping sounds exactly as you've described: you crank it up and the sound becomes harsh. You crank it up with the Phoenix and you're fine because the Phoenix is a desktop amp and has a higher voltage swing.

 

[moonboy403]

It just so happened that Headphoneaddict is able to drive his K1000 with the Amphora,

"For a lark I tried my new K1000 on the Amphora (with my 4-pin to SE adapter) and on the Single Power balanced. Up to the volume limit of the Amphora there was no clipping and the sound was clear, just not as loud as I would like to normally listen to them."

We were auditioning the Amphora with a D7000 here guys.

Moreover, here what he said on his SP Square Wave XL and his Amphora,

"They both drive two headphones at the same time, but the Amphora can drive two low impedance phones at the same time without flinching and the Sq Wave XL struggles to do that. "

So I really don't think power is lacking here.

 

[seacard]

Quote:

Originally Posted by moonboy403 /img/forum/go_quote.gif It just so happened that Headphoneaddict is able to drive his K1000 with the Amphora, "For a lark I tried my new K1000 on the Amphora (with my 4-pin to SE adapter) and on the Single Power balanced. Up to the volume limit of the Amphora there was no clipping and the sound was clear, just not as loud as I would like to normally listen to them." We were auditioning the Amphora with a D7000 here guys. Moreover, here what he said on his SP Square Wave XL and his Amphora, "They both drive two headphones at the same time, but the Amphora can drive two low impedance phones at the same time without flinching and the Sq Wave XL struggles to do that. " So I really don't think power is lacking here.

I don’t want to question Headphone Addict because he is a great guy, but the idea that the Amphora can drive the K1000 loud enough to the point where you can accurately assess the sound and even tell whether the sound is bright or harsh is a bit far-fetched. On the other hand, I haven’t seen Amphora’s published output power so I am not qualified to comment on it.

Here are the specs for the Amphora:

Input impedance – 20k
Output impedance (preamp outputs) – less than 100 ohms
Inputs - 2 sets
Headphone outputs – 2 sets
Preamp outputs – 1 set
Gain – Switchable 0dB / 12dB
Battery - 9V Li-Ion
Play time between charges – greater than 24 hours
Charger – Li-Ion auto-charger. Fully charges in less than 4 hours
Charger input voltage – 100Vac – 240Vac, 50/60Hz

What's the impedance on the Denons? 25?