Speaker Amps for headphones

Anyone else use a speaker amp to drive their headphones? What do you use? Why? What are the best speaker amps for driving headphones? What kind of adapter do you use? I guess some speaker amps can only be used balanced.

I have a First Watt F7 right now and curious to try other amps and get chatty with the locals.

 

I use a vintage Adcom GFA 535. Cost me all of $125.00 10 years ago. It brings out the best of my HE6SE.
Did a diy xlr wire with parts from Markertek, canare wire and a neutrik connector, tinned the bare wire amp connection cause this amp has unconventional speaker taps, banana's and spades won't work. $10 +-. Added some odds and ends to get the cart looking sensible for shipping. I now have bits for any type of screw I'm ever likely to see.
There may be a headphone amp that makes these phones sound better, The Black AMP, Jot2, phonitor e leave something to be desired.
I did try an Adcom GFA 5500. 200 watts vs 60 watts and had no improvement so I sent it to TMR to be flipped..
Be sure to color code the speaker side left right - + to make the hook up easy. I have seen some boutique cable shops sell a finished version if you don't want to diy. That amp that @Zampotech is developing would likely do well.

 

I have tried a few different amps. I started with a Pass X150.5 since that's what I had from my speaker setup and I wanted to see what more power would do for my Susvaras which are obviously one of the most power hungry HPs out there (83db/mw 60 ohm). The difference was not subtle...the soundstage opened up and the bass very significantly firmed up so I was hooked. I did try this setup with various other HPs (VO, Aeon, HEK SE, HD6xx, HD650), but there was buzzing/noise from them. Given the inefficiency, I did not hear this from the Susvara and only very slightly from the LCD-4 (which also saw some improvements, but less dramatic than the Susvara). I then tried a Pass XA25 which for me was a fantastic pairing. The XA25 is has a much lower noise floor (50uv vs 200uv on the X150.5 and most of the other Pass amps). The sounds just seemed to come out of nowhere with such a black background. This significantly reduced the noise/buzzing, but it was still perceptible with the more sensitive headphones.

I also at one point tried my Primaluna amp. Because it's an OTC amp, my understanding is that it is bad for the tubes to have a load that is much higher impedance (effectively looks like open circuit since there is minimal current flow) than the amp was rated for (i.e. 8 ohms). My understanding is that the power in the transformer will be reflected back into the tubes since it has no where else to go (someone please correct/clarify if I misunderstand) which is bad for the tubes and potentially the amp. So, I just put a couple resistors across the binding posts in parallel to bring the effect impedance of the HP + resistors down to what the tube amp expected (i.e. 8 ohms). I initially just stuck the resistors directly on the binding posts along with the speaker tap cable using spades, but did worry about how insecurely that was mounted and eventually just bought some bananas for the resistors. This worked pretty well, but I had to tube roll to get the bass performance to where I wanted.




You can have blue jeans cable make a custom speaker tap cable out of belden speaker wire for $53.



Hifiman also makes their HE-1 adapter box which I understand to just put resistors in parallel and in series and I have heard anecdotal reports though that this box introduces a bit of a veil to the sound.

 

I've used the vintage Pioneer M-22 in the past (using a very simple DIY speaker tap) with Audeze LCD-XC. This is a good amp for headphone use, never had any issues with pop at power on/off or hum. Keep in mind they are low impedance and pretty high sensitivity (100 dB/mW).

 

I was about to use my old NAD amp for Diana V2 but ended up using the amp for speakers. Anyway, the point of my post is, DIY resistance network is really easy and cheap to make. Just do Robinette and you're good to go:

https://robrobinette.com/HeadphoneResistorNetworkCalculator.htm

 

I use a Pioneer M22 and 45 push pull amp (7W into 8 ohms) for all of my headphones. Why? Because I don't want to spend money on separate amps for electrostatic and dynamic headphones AND speakers.

 

I use a Quad 405 to power my he6se. I use an xlr to banana plug adapter I had made and connect them directly. I rather like it, it balances out the incisiveness of the he6se with a somewhat more mellow (without being warm) presentation.

Why? I had the quad for a long time unused, despite being fond of its sound, and I needed an amp for my he6se after I sold my mjolnir 2. Turns out I like this synergy better.

 

I picked up a crown cdi1000 for $200 after reading about it on this forum. Using it with ec zds as preamp to feed into the he6se v2 with a Yggdrasil A2 as dac. Had blue jeans cable make me couple of custom cables from rca to phoenix connector on the CDI and fork connector out to xlr to connect with the headphone, so basically directly feeding 500w into each channel.
Sounds great, really fast attack and impactful initial bass slam, just wish that the bass decay is a bit longer. A nice complement to utopias. Haven't dared to run the utopias through the CDI though and really don't have a cable for it.

 

Twins! Love mine. How do you like it with the HE6? That was my daily combo for quite some time... Now my F7 drives my JBLs.

I'd put the F7 as headamp up against any other SS headamp I've heard without hesitation in terms of raw performance. I've even used it with fairly efficient dynamic headphones. If it had a 4-pin socket on the front and a switch between the taps and that socket, it'd be my one-and-done amp and I don't think I'd feel like I was missing out on much.

 

Whats the DC offset like?

 

sorry, I have no idea. Never thought of measuring it for such a budget solution and don't have a multimeter on hand.

 

I’ll probably never sell mine on here after saying this but I’m not impressed. I know from experience with DIY amps that even a good build with good quality parts does not a good amp make. I’ve experienced too much variation in DIY amps that have no real explanation. Including the awesome performance of my not so humble Cavslli SOHA1 which beats the F7 even with the HE6. Which should not physically be possible. My F7 just sounds lean and doesn’t outperform my SOHA in any technical way. And before I got an iFI GDN Defender for the F7 it was seriously bass lite. So I don’t know. I’m looking into getting a different First Watt amp and may have just found one.

the amp is so big and heavy I have to keep it under the head of my bed and run 1.5m rca cables from my PO-2XR and a 1.5 meter banana plug to 4 pin XLR cable from the amp up to me. Maybe this is the problem? But I would think if this was an issue it would cause treble roll off not a lean bass lite signature.

for reference the Jotunheim has very similar tonality to my SOHA (but less power) and the F7 is leaner than both and more solid state sounding. Which I don’t think it should be.

but I’m still into the idea of getting a nice speaker amp for my orthos. Probably a different First Watt.

 

I bought one of those cheapish ali Dartzeel clones to use as a headphone amp until my DG300B gets built:


I can’t say it’s the best SS amp I’ve heard but when paired with my Exogal Comet+ it’s definitely warm and relaxing. The downside is both the amp and the Comet seem to blunt transients so I can’t rock out with it as much as I want to. I originally half expected to just buy this for the chassis and shove a Firstwatt clone in so the fact that it works for now is a bonus enough for me. It even has a built in start up relay.

 

DIY First Watt F6 clone on usaudiomart for 850$

 

One caveat to point out is @E_Schaaf likely has a commercial F7, while @rhythmdevils has a diyers best guess at an F7 as the official DIY schematics have not yet been released by Nelson. Most of these DIY guesses are probably pretty close but something may be holding this amp back. I wouldn't have expected it to have any trouble driving headphones and the lateral fets should give it an overall smooth response. Time will tell...

 

My daily driver for HP1:
Sansui 2000a (1969, 100% stock)
Doesn't sound great. Some mid bass boost and treble is hazy , but is at least is better than several SS headphone amps. Jot 1 was the other SS amp I had earlier and the sansui absolutely shames it.


Bought this one for a friend and had it for two weeks to test- Sansui G7500 (100% stock)

All I know now is I either want or a Sansui G7500/7700 or an au-X1. The G series Sansui sounded so grand and aggressive with kind of macro dynamics that simply no headphone amp can even dream of.
Not all G series are good though. G5000 was quite hard sounding. Some other Sansuis weren't great either - AU719, D9, AU517 (Not bad but too much of SS cleanness/simplistic sound)
AU9500 was goood! Very coloured but in a hypnotic way
Another good one , Quad II:

Limited power aside, it sounded very nice. Return of microdynamics, thats where even the good Sansuis are not at par with good tube amps except for maybe the AU X1

Since ones below weren't anything special I didn't bother remebering model names for all

Mediocre ones:
Marantz DC series/2523/4300
Luxman Alpha M06 Class A
Luxman M03
HH Scott 223B
Romulous (some chrome chassis tube amp)
Vintage JVC amps (cheap and not horrible)

Garbage:
Anything from Kenwood/Akai/lower Luxman units/Denon/HK/Crown/Red wine audio (Some chip amp, absolutely hilarious for the price)/First watt clone (dunno what model)