OK, time to update the headphone amp vs integrated amp/receiver headphone jack debate as I promised.
Sorry for the length but I've a lot to cover.
The following is simply my opinion based on discriminating (and sometimes not so discriminating
listening for over 40 years, plus direct comparison of a top of the line (TOTL) 70's classic receiver headphone output to a MAD Ear+ HD Purist. The HD is generally considered to be an excellent stand alone tube based amplifier available at a very good price.
I've been considering a SS stand alone amp to complement my own tubed HD Purist. But like many of you, I've already spent too much money on this hobby.
This thread and a thread on audiokarma.org about headphone jack output motivated me to do some experimenting with the classic SS amps of the 70's.
Here's a statement and quote from the audiokarma thread:
The poster states the headphone out on his amp from the 70's sounds excellent. Then says:
"For comparision I use Sennheiser hd600 headphones with a Headroom Max headphone amp....so if something sounds good compared to the Max it sounds GOOD." He was talking about his TOTL Kenwood amp from the late 70's. And the Headroom Max sold for $1,887 before it was upgraded/discontinued.
That got me moving.
My TOTL (for 1977!) Sony 6800SD receiver has arrived. Paid about $150 including shipping on ebay for it. ( http://cgi.ebay.com/ws/eBayISAPI.dll...MEWN%3AIT&rd=1
) Plus I have a near TOTL Kenwood amp due next Thursday, (more info here: http://audiokarma.org/forums/showthr...highlight=7300
) but I've enough good info from listening to the Sony to post some conclusions.
First a description of the Sony so we know what we're talking about.
It was Sony's top of the line receiver for a year before being displaced by the 7800SD, originally sold for $600, and pumps out a VERY conservatively rated 80 watts/channel.
It uses a stepped attenuator and a transformer the size of a coffee can. The headphone out is directly driven by the main amp with just one resistor in line to step down the juice. No wimpy little add on board for the headphones here.
Just a quick off topic paragraph about the Senn 600 series. Boy do they need juice.
When used to drive speakers I usually set the volume knob of the 6800SD three steps from fully attenuated which is not quite 9 o'clock. When driving the 600/650s, I have to set it at 12 o'clock. My gosh, that's a lot of juice. Just for comparison, Westone UM2's and Senn 595's settings are more like the speakers. Mind you, I'm talking about listening LOUD, which I do with certain rock albums or even E Power Biggs playing church organ music. This type of music is meant to be played loud.
The quick comparison:
MAD Ear+ Purist HD. ( http://mapletreeaudio.com
) This amp is a beauty. Very, very clean and very, very smooth. It doesn't add anything to the music at all IMO. But if you change the output tube, you can change the character of the sound.
Use a clinical tube and you get clinical sound. Use a rich, guttural sounding tube and that's the sound you get. This amp is an extremely good value at between $500 and $600 depending on options. Very rich bass, very smooth highs both reaching the limits of what we can hear and a bit beyond. Not quite as tight as SS but much smoother and plenty tight enough. A sound I prefer for most but not all my listening. And oddly enough the more I listen to this amp with the Senn 600/650's the more I like the combination.
Sony 6800SD sound: The headphone jack output is surprisingly good. Very clean, very transparent. No coloration to speak of. It holds its own against the HD Purist in all but the very highest frequencies. A smooth sound for solid state (Sony's of that era were considered sweet sounding). Only the tiniest touch grainy at the loudest volumes. Bass is excellent and tight, as good as you can ask for even at the loudest listening levels. Concert level bass with the right phones.
I considered the highs very slightly grainy, but only at loud listening levels and when directly compared to a dedicated tube amp. Still very, very good when compared to most solid state, including dedicated amps. All in all a great value. You'd have to spend way more than $102.50 in a dedicated amp to get anything approaching this sound.
Is the HD Purist or another dedicated headphone amp worth the price differential when compared to a headphone jack?
Good question for most. But in my opinion, absolutely, IF you prefer tubes. I listen to a LOT of music. The HD is so smooth, listener fatigue is not an issue at all. Plus the ability to change the sound by taking a few seconds to swap a tube is invaluable.
Headphones and amps are expensive, tubes are relatively cheap. When looking for that elusive perfect sound, the flexibility and purity of the HD is unbeatable.
But that's for a fussy listener who favors tubes. If I favored SS or if I were a college student, or even an audiophile on a budget, headphone jack output of the amps from the classic period is hard to beat.
Why no mention of tube amps/receivers. Because I didn't try one. But also because they are relatively uncommon compared to SS and hence more expensive. Plus tube receivers/amps need many tubes and good tubes are expensive to replace.
READ THIS PART!
The headphone jacks of receivers built after the receiver/amplifier wars of the mid to late seventy's generally are not very good, in fact IMO they suck, not to put too fine a point on it. Don't get me wrong, there is fine output to be had from some contemporary receiver headphone jacks. But it is rare and takes some hunting and is gnerally not available in cheaper models.
In my review/comparison I'm ONLY talking about the headphone outs of top of the line receivers and amps from the glory days. A period roughly from 1973 through 1981. After that the price wars came and quality went down hill quickly.
BTW the low and mid price amp headphone outs of this vintage solid state period, while still pretty good, aren't worth the price savings. We're only talking of $50-$100 or so to step up to TOTL after all.
Make absolutely sure the headphone jacks of the amp/receiver you are considering is connected to the main amp circuits. No separate board for the headphone out. Other than that check audiokarma.org and other forums of that type, lots of good info about what were the best vintage TOTL models. Then hunt through the for sale listings. Check as many sites as you can find including ebay. Then be careful. Lots of bad old amps on their last legs out there. Plus capacitors age. This means the higher frequencies might be missing even if everything else is working fine.
Bottom line in my opinion FWIW:
Lots of caveats, but if one is on a budget and has the time and patience to find the right classic amp/receiver with a headphone jack driven directly from the main amp there is no need to spend big bucks on a separate amp for your headphones unless you need the absolute best sound.