Hello fellow humans.
I have the opportunity to own both the infamous Icon Audio HP8 Mk.II Signature as well as the Cayin HA-3A tube amplifiers. These units are ZMF lovers favourites. I personally had a lot of questions about how they compare when deciding to get into tubes, and I noticed throughout a good number of threads, quite a few others had questions as well. I couldn't find anywhere else on the interweb where the HP8 was compared in depth, and there are only one or two english reviews. Well, now I own both, and have the opportunity to give a brief overview of the differences. Both units are using their default tubes (no tube rolling yet).
Tested on:
- ZMF Caldera, using default ZMF caldera medium lambskin pads.
- ZMF Atrium Open, using ZMF auteur hybrid pads.
- Focal Clear using ZMF Suede Sub pads.
The HP8 only offers 6.35mm single-ended and a Youkamoo adapter which appeared to have no impact on sound signal or quality. The Cayin was heard through balanced XLR and 4.4mm.
The Cayin HA-3A
My Cayin was was made in 2022 and is the “B” version that uses a different set of default tubes (EH 6v6, JJ 12au7, RCA 25AX4GT). It's noise floor is predominantly black on low impedance setting. Was not expecting that as the Cayin HA-XA series is known for issues with impedance matching and noise. I can hear a bit of noise on medium and a bit more on high, but the ambient noise of traffic outside is more noticeable than the noise coming through the connection. Also tested my 12.6ohm Unique Melody MEST Mk.II’s in the 4.4mm/low imp. And again heard minor hum (if I really listened for it) on low. The noise floor rose to audible levels on medium and high.
Sonic characteristics (+vs the HP8 Mk.II):
- First thing that comes to mind is “layered air”
- Surprisingly girthy sound. Especially up top.
- Much slower decay than the HP8, but somehow doesn’t translate to sounding slower.
- More of an edge on it than the HP8; HP8 sounds bolder, but the notes have softer edges.
- Ever so slightly bigger soundstage vs the HP8 (like 10~15%, maybe)
- Character of the HA-3A is fast, and lively. Seems in contradiction to some people’s description as “delicate” or “nuanced”. I don’t know that I’d use either of those words to describe what I’m hearing.
- Bass feels airier than the HP8, and more present, but less controlled. It’s funner, but more fatiguing.
- Midrange sounds less well imaged than the HP8. HA-3 can get congested.
- Less concerned with articulation, instead aiming for a specific rich-of-neutral tube timbre
- Again, intensely layered sound. Can almost touch the layers of air; well defined soundstage
- Switching to the Atrium open, the headphone now sounds slowed down. A romantic headphone now sounds moreso
- What the HA-3 wants to do is translated perfectly to the Atrium O. The experience is rich, dynamic, and even more lush.
- The upper range has more presence, locality and sparkle. The HP8 does this also, but the Cayin has even more. The biggest surprise thus far.
- SIGNIFICANT texture boost.
- The Focal Clear didn't really like this amp IMO. Not that it did badly, but the amp somewhat muddied the presentation, at least with the factory set of tubes. I don't think anyone who bought and likes the Focal Clear is after this sound signature for what the Clear does with sound.
- I can imagine this reversing with brighter tubes.
The HP8 Mk.II Signature edition
My HP8 was made March 29th, 2023. It's equipped with the default set of tubes (Electro Harmonix 12AX7, 2x David Shaw Signature CV181 (6SN7)'s). Listened with no music, I hear no noise on the floor whatsoever; it's pitch black. That being said, I have noticed the right tube is slightly noisier than the left. Every now and then, it starts "fuzzing" for a minute or two, but this goes away. It is probably picking up a signal from something (?).
Sonic characteristics (+vs the HA-3A):
- Bold, yet soft. Very full bodied. I can’t imagine anyone wanting a SS vs this.
- Somewhat wider portrayal of the FR versus the HA-3; The HP8 can be more delicate. Quiet segments are quieter, loud segments are louder & more forceful.
- Soundstage is slightly smaller but more localized; less air, but traded for more holography. It wants you to enjoy the music, but it still wants to impress you.
- More sparkle on the top end; highs have a crystalline nature, and whilst the HA-3 has a slower roll off, the power of those high notes stays with you a moment longer.
- Articulate, yet smooth. The HP8 is in fact addictively smooth, generally great and extremely inoffensive.
- Many people seem to prefer the medium impedance setting with the HP8. I found medium made the sound signature very forward and sometimes very unpleasant. For some of my test-tracks, the soundstage disappeared and I felt like I was trapped in an elevator with the band. Low impedance with a higher listening volume seemed to do a better job preserving the character of the music.
- This however was not the case with the Atrium Open. WOW is the word. Medium did a much better job of powering the 300ohm dynamic, and the HP8's accurate, bold, and confident timbre did the AO WONDERS. For a headphone that doesn't change much via source, It was a clear upgrade for the Atrium.
- The Atrium kept it's original warmer, and romantic timbre, but now benefited from a mild soundstage boost, and was a little sharper in the imaging. Again, the initial attack of the notes just wanted to stay with you a moment longer making the Atrium sound not only inviting and romantic, but bolder, stronger, and more muscular.
- The top end also received a sparkle boost, but not as much as the HA-3.
- Switching to the Focal Clear, it again sounded much better on the HP8. No contest. The timbre of the HP8 is just far more suited to the fast, punchy, resolving nature of the HP8. The HA-3 in comparison sounded like it wanted to Focal to do something that wasn't in it's wheelhouse.
After thinking about it for a while, I really was able to put into words the difference between the two tube amps, and I really do think it’s accurate: The HA-3 makes everything sound like a live performance. It makes you feel like you’re at the bar and listening to the band play on stage. The HP8 in comparison, sounds like you’re at a theatre. Not in terms of soundstage, but in terms of the character of It’s sounds which I’d peg as almost…”professional” in comparison.
The HP8’s body is smoother, and more articulate. But, the HA-3 has a forwardness to it’s texture you don’t get from the HP8, at least not with it’s default tubes.
This all being said, I absolutely understand why people would feel the HP8 is the better amp. It’s an excellent, somewhat more traditional sound that doesn’t make anything sound bad, and makes everything sound amazing. It has literally no downsides that I can hear. It's entirely possible to buy this amp, never modify it at all, and be happy for the rest of your ownership.
The HA-3 on the other hand took me to different places that I couldn't believe (this amp made me cry...). But, at the same time there were also 2 or 3 songs I came across in my collection that the amp didn’t do anything for whilst I thought this song blew my mind on the HP8. The HP8 was immediately amazing, where as my first reaction when turning the HA-3 on was “...Oh?...ok…” until I realized what it was trying to do. In comparison to the HP8, if you bought the HA-3 I would say it would be best to tube roll.
Ultimately, neither amp is the obvious best, I think both amps are actually surprisingly different, which was entirely unexpected.
All of this being said, I’m planning my NOS tube purchases as we speak…
HA-3A goes first...going to see if I can get it a step closer to the HP8's signature without losing what the HA-3 does best.
I can move threads if need be since this is the amp thread. Looking at the Soekris DAC 2541 or Brooklyn Liberty DAC II. The MHDT Orchid looks nice but I can't figure out how to source it new. Gustard A26 also on the list. Similar price range as the amp: up to ~$1500 with some wiggle room.
