Using full sized integrated amp - Page 8

Hi! I´m new in head-fi, but have been hearing by headphones for at least 20 years.
Now I have a Sennheiser HD565 feeded from the headphone jack of a NAD 3240PE. I didn´t compare it to other (integrated od dedicated) amps.
Scompton, I like what you wrote about the NAD3155 (which I wanted to buy just after it went off market, I got the 3240 instead). Does the 3155 just use a resistor between main (speakers) out and phones jack (like the 3240)? Or does it have a dedicated circuit.
Do you think I should be satisfied with my 3240? Or would a cheap dedicated headphones amp for few hundreds of Euros (like Pro-Ject) increase sound quality?
Thanks for giving your opinion!

KonstantinT - I recently contacted NAD about their current line of amps and receivers. I was told that ALL their systems have headphone jacks that are resistored off from the main amp.

It's best to ask NAD, but I doubt NAD ever went the opamp route. My guess is that the two amps you mentioned both use resistors.

I have the service manual for the 3155 and it uses resistors.

There's been a lot of disagreement about this over the years on various forums and newsgroups (I've been involved in most of them, I think ). Thanks to Ebay I've had the opportunity of looking inside a great many 90s amps and receivers and it's clear most HP jacks are run off the speaker oulet via resistors. (In fact on one, a Rotel RA931 MkII, I actually snipped the resistor bodies off the leads and soldered on higher value resistors--this was before I thought of making up my own little resistor box). I don't see why this is so hard for some people to grasp as its common sense--the cheapest way of doing things, which is always common sense to manufacturers; yet I still see people posting here that most amps/receivers use op amps worth a few cents, this apparently being the justification for spending hundreds on dedicated HP amps (many of which--ha!--use op amps). If you think about it, using an op amp in a speaker amp would be cheating. When people plug headphones into their amp, they expect the same signal as is being sent to their speakers. Even if they're not dedicated HP listeners they may have expensive phones, and quite likely they selected the amp on the basis of reviews--reviews based on the amp's performance through speakers. So they should fairly expect the same sound through the HP jacks as through the speaker connections. And of course dedicated HP listeners like ourselves have even more right to be able to select an amp based on reviews and get the same sound the reviewer gave 5 stars to. Now I know none of this will stop the myth of the 10c op amp, but I do hope this thread inspires a few HP users to experiment with the amps they may already have or can acquire cheap on ebay. They may be surprised what quality is on offer right under their noses.

And I heartily agree that this thread should be a sticky.

I have a question. Has anyone considered the larger "green footprint" when running a receiver/integrated amp (made to drive speakers), only to use it's amp driven headphone jack to drive their headphones?

Seems like a lot of amp for that purpose, power wise? Thoughts?

Power is one of the concern that keeps me flirting with a dedicated headphone amp. I don't have a number, but I guess my five channels power amplifier (2x100w, 2x50w, 1x110w) uses multiple times more power at idle than any dedicated headphone amplifier at work. Especially considering that I am hesitant to turn it off so that I don't have to warm it up again.

I hadn't thought about that, Penchum. But I wonder...how long would it take for the extra carbon in my footprint that would be created by having two separate components manufactured, to be passed by the power used by running a 40 watt amp to power headphones. A while, I'd guess.

Tim

Well Tim,

I think there are a bunch of variables, and I'm not one of those fanatics on power usage, but here is an example worth looking at:

I have this Pioneer Integrated Amplifier here, an SA9500II, it's all restored and working like a champ. It has an excellent headphone jack, it can produce 80 watts RMS, and it draws 200 watts world voltage model. The 220-240V only model draws 560 watts.

I have a Pioneer SX-780 Receiver in the living room, all restored, with a nice headphone jack, it can produce 45 watts RMS, and it draws 150 watts.

I have this Yamaha C-40 Pre-amplifier here, that has an excellent onboard discrete headphone amp, it's all restored and working great. It draws 13 watts.

So, even if I'm not comparing dedicated headphone amps to receivers/integrated amps, there is still a sizable "draw" difference between these three units. I could easily be happy listening to any one of them, but hell, saving 187 watts by making a choice, doesn't sound like too bad of an idea. That's like turning off 3 incandescent light bulbs.

Trying to equate the manufacturing processes into a personal "carbon (green) footprint" doesn't pan out to be much of a "personal" incentive. They are going to crank up those robots and make them anyway, because they are still selling. Buying older receivers/dedicated amps for headphone purposes doesn't equate well either. The damage has already been done, years ago. What they draw now, is the only true carbon footprint consideration in these nice old units.

The only place where you and I are empowered to make a difference, is in how much we "draw" from the grid. The choices we make may have only smaller returns associated with them, but multiply that by a large number of people making similiar choices, and the returns get big fast.

I just don't have any idea about how much dedicated headphone amps draw, it is not well advertised it seems, but I'm reseaching it.

This is a very good point, and indeed I consider it the chief reason to consider a dedicated HP amp--not improved sound quality as I can't detect any. I happen to occasionally use speakers as well for my LCD TV which has lousy sound, so I need an integrated, but in times past when I didn't, I sought out and owned many pre-amps, for exactly the reason you've raised--low consumption. Indeed I've even sold a couple of excellent sounding amps (Marantz PM8200, for one) because they ran very hot and were clearly draining the grid, and rejected others listed on Ebay after discovering their power consumption figure (Technics 'New Class A' and 'Class AA' are terrible in this area). So this is a genuine consideration and a good argument in favour of dedicated HP amps---that and, where it matters, portability. Of course it doesn't obviate the argument I've been advancing, that when newbies post here about amps for their newly acquired HD650, AKG 701 etc, they should not be automatically directed toward dedicated HP amps but advised to seriously listen to the speaker amp they may already have before spending more.

There's also the matter of how long one leaves one's amp on. I know with me there's a tendency, when I know power consumption is low, to leave the amp on permanently. When I can feel the heat from the other side of the room, I turn it off at every opportunity.

One last point. Amps like the LD MkV resemble integrateds anyway in their design. I wonder what the consumption of an LD MkV is?

I've got a message off to DavidZ, to see if they already have that info or not. Soon as he replies, I'll post it up. I'm curious too.

Why not follow the green argument further? Why are you using a headphone the requires an amp in the first place? The difference between headphones like the HD595, AD2000, AD900, D2000 (in my opinion don't require an amp) , and the HD600, HD650 K701, DT880 (in my opinion could use an amp) exist on a microscopic scale for people who are not hard core audiophiles.

I'm not advocating giving up your power-hungry headphones, but a dedicated amp for a pair of headphones would not even be an issue if certain headphone manufacturers improved the efficiency of their headphones. If Sennheiser made two versions of the HD600, one more expensive (even $100 more expensive) with the efficiency to run well from portable/sound card sources, I'd buy it. An extra $100 for the heapdhone is still cheaper than any decent headphone amp, even if I built it myself.

To be honest I don't even understand why some headphones require an amp in the first place. If some top of the line headphones improve very little with an amp, why not all of them? People have asked this question before. Nobody seems to have an proper answer.

Can anybody guesstimate the power consumption of a dedicated SS headphone amp? I'm going to guess 1W. Does that sound about right?

What about a modern stereo integrated? The HK 3490 seems to have <1W idle and 310W max. The NAD 315BEE is 22 watts in idle, 185 watts max. I'm guessing if either power headphones it will be at 40~50 watts at reasonable listening levels. Sound about right?

I realize the only way to really figure this out is with a wattmeter, but I don't have one. The 5.1/7.1 receivers seem to really eat up electricity, even more so than the stereo integrated.

--edit--

I just looked up the specifications for the CK2III and the power supply for the M3. The transformer for the CK2III seems to be able to suck down a maximum of 7VA. The sigma11 power supply transformer is 25VA! You don't even want to know about the sigma22. I understand that the power supplies are probably rated much higher than the actual draw, but I'm now really curious how much power these amps consume.

The Zana Deux, I believe Craig Uthus told me, uses about 200 watts.

And SOUNDS like it does!

Headamp list the power consumption for 2 of their home amps:
Gilmore Lite - 7.5 Watts
GS-1 - 15 Watts

Meier Audio list the power uptake of 3:
Arietta - 2 Watts
Cantate - 6 Watts
Opera - 12 Watts

I'd be curious to see a comparison between solid state and tubes.

Does anyone know how you get a thread considered for a sticky? It's a shame for all this to just disappear into the void.

(Even if there are those who would prefer that it did).