[Michalmk6]

Yes, I’ve fed my HPA4 with both a Feliks Echo 2 and an LTA MZ3. Provides some nice options depending on my listening mood. Also allows the HPA4 to drive the headphones while still getting the tube sound.

Thanks. Have you noticed any differences in sound between listening to your tube amps separately and when using them as a preamps? Do you connect your Feliks Echo2 to the HPA4 with RCA to XLR cables using balanced stereo inputs or you just use a pair of RCA cables?

 

[Fysty]

Thanks. Have you noticed any differences in sound between listening to your tube amps separately and when using them as a preamps? Do you connect your Feliks Echo2 to the HPA4 with RCA to XLR cables using balanced stereo inputs or you just use a pair of RCA cables?

I haven’t noticed any difference to be honest. The tube amps sound the same through the HPA4. I connect using high quality RCA to RCA interconnects as I see no advantage going unbalanced to balanced.

 

[Michalmk6]

I haven’t noticed any difference to be honest. The tube amps sound the same through the HPA4. I connect using high quality RCA to RCA interconnects as I see no advantage going unbalanced to balanced.

Got it! Thanks again.

 

[Michalmk6]

Just one more question. Have you tried the opposite connection (HPA4 as a preamp)? If yes, have you noticed any difference? Thank you.

 

[Michalmk6]

.

 

[genefruit]

Not the responder to your original question but I expect if you're looking to drive difficult headphones, having the tubes serve as the pre into the HPA4 is going to better serve your mission to drive difficult headphones. Having the clean HPA4 feed the tubes will provide a clean signal but won't provide the additional amplification that I expect you're looking for. Ultimately, if you have the tubes and the HPA4 you can try to your taste and report back.

 

[briantrinh86]

does anybody pair hp4 with hifiman susvara? is it enough power to fully drive the susvara and how the susvara sound with hp4?thanks

 

[Michalmk6]

Not the responder to your original question but I expect if you're looking to drive difficult headphones, having the tubes serve as the pre into the HPA4 is going to better serve your mission to drive difficult headphones. Having the clean HPA4 feed the tubes will provide a clean signal but won't provide the additional amplification that I expect you're looking for. Ultimately, if you have the tubes and the HPA4 you can try to your taste and report back.

Thank you. Yes, I understand that the HPA4 as a pre is not going to give the additional amplification. I was just curious if there is any difference in sound between those two setups.

 

[BassicScience]

does anybody pair hp4 with hifiman susvara? is it enough power to fully drive the susvara and how the susvara sound with hp4?thanks

I had an HPA4 on a trial basis for a few weeks, and it drives the Susvara to acceptable volume levels, albeit without a ton of extra headroom. The combo sounded fine, but inserting my NAD M22 V2 amp into the chain and using the HPA4 as a preamp was a very clear sonic upgrade to my ears.

 

[Fysty]

Just one more question. Have you tried the opposite connection (HPA4 as a preamp)? If yes, have you noticed any difference? Thank you.

Sorry I missed this. I have not hooked it up the other way as I have had any reason to.

 

[Michalmk6]

Sorry I missed this. I have not hooked it up the other way as I have had any reason to.

I understand. Anyway, I'm picking it up tomorrow from my local store.

 

[lumdicks]

does anybody pair hp4 with hifiman susvara? is it enough power to fully drive the susvara and how the susvara sound with hp4?thanks

HPA4 drives Susvara just fine but not great, with almost no headroom left. In my case, I am using HPA4 as pre and Burson Conductor 3XR / Kinki THR-1 as poweramp and it sounds quite substantially better in dynamics, soundstage, quantity of bass and smoothness of high.

 

[lumdicks]

Thank you. Yes, I understand that the HPA4 as a pre is not going to give the additional amplification. I was just curious if there is any difference in sound between those two setups.

The HPA4 will not bring any amplification as pre-amp but its line stage is at reference level, and it improves resolution, imaging and background darkness significantly in my case with perfect control on volume.

 

[Stereolab42]

I'm sure many people have figured this out before me but the key to properly enjoying the HPA4 is simple -- get a DAC that can do +24 dBu out. Benchmark even says this in the manual, to quote: "Tip: We recommend using professional-grade balanced XLR interconnects that provide +24 dBu at 0 dBFS. Consumer-grade balanced XLR interconnects operate at levels that are about 10 dB lower (4 Vrms or +14.2 dBu at 0 dBFS)." I did read that upon purchase but didn't fully understand the implications at the time.

Specifically, the HPA4 is unity gain at 0 dB on the volume control, with only +15 dB of additional gain available on top of that. In other words, a consumer-grade DAC with an XLR connection to the HPA4 can at most result in 4v from the headphone jacks with volume at 0 dB. This is no problem for the vast majority of headphones, but it leaves the Abyss with little headroom if you're playing a quietly recorded track or have some DSP in the chain like crossfeed or bass-boost. And apparently the Susvara (which I don't own) hurts even more.

The solution? Get a DAC that can do proper +24 dBu out, like the RME ADI-2 Pro (which I now have) or one of the Benchmark DACs. This limits your choices of course; you'll need to shift focus away from boutique consumer manufacturers to those more in the pro audio space, but if you're of a more objectivist bent like me then that should cause no worries. Now your volume control is rocking out 10 dB lower and you have plenty more space. This doesn't get you any more power (watts/current) of course... it simply allows you better ACCESS to that power. Certainly it's got the Abyss TC fully covered. The insane Susvara might still be able to pull more power than the HPA4 can provide, but I'll leave that to others to experiment; as someone who's not a fan of HiFiMAN's house sound I'm never going to own one.

 

[LCMusicLover]

I'm sure many people have figured this out before me but the key to properly enjoying the HPA4 is simple -- get a DAC that can do +24 dBu out. Benchmark even says this in the manual, to quote: "Tip: We recommend using professional-grade balanced XLR interconnects that provide +24 dBu at 0 dBFS. Consumer-grade balanced XLR interconnects operate at levels that are about 10 dB lower (4 Vrms or +14.2 dBu at 0 dBFS)." I did read that upon purchase but didn't fully understand the implications at the time.

Specifically, the HPA4 is unity gain at 0 dB on the volume control, with only +15 dB of additional gain available on top of that. In other words, a consumer-grade DAC with an XLR connection to the HPA4 can at most result in 4v from the headphone jacks with volume at 0 dB. This is no problem for the vast majority of headphones, but it leaves the Abyss with little headroom if you're playing a quietly recorded track or have some DSP in the chain like crossfeed or bass-boost. And apparently the Susvara (which I don't own) hurts even more.

The solution? Get a DAC that can do proper +24 dBu out, like the RME ADI-2 Pro (which I now have) or one of the Benchmark DACs. This limits your choices of course; you'll need to shift focus away from boutique consumer manufacturers to those more in the pro audio space, but if you're of a more objectivist bent like me then that should cause no worries. Now your volume control is rocking out 10 dB lower and you have plenty more space. This doesn't get you any more power (watts/current) of course... it simply allows you better ACCESS to that power. Certainly it's got the Abyss TC fully covered. The insane Susvara might still be able to pull more power than the HPA4 can provide, but I'll leave that to others to experiment; as someone who's not a fan of HiFiMAN's house sound I'm never going to own one.

Interesting. But there’s a gap in my understanding. Is the issue simply a matter of not being compatible w/ power-hungry cans? Or is sound quality impacted by lower voltage inputs? In other words, will my (easy-to-drive) Utopia sound worse if driven by my TT2 in DAC mode vs Amp mode ‘cranked up’, assuming I adjust the HPA4 to match volume?

Thanks.