[yyzSB]

I was talking on A'gon with a well know component designer about XLR cables. He was of the opinion that for XLR connections that support the XLR AES48 standard it would not matter too much which interconnects are used. The Benchmark gear does support this standard (I asked) and they themselves say on their web site that you only need a certain type of low cost professional grade interconnect. They specify a cable that can carry a 24 dBu signal and called them professional grade cables. I am using some expensive Audience XLR's. I do not have any spare XLR's to compare one against another, but I am under the impression that my XLR's are consumer grade and cannot carry the signal at Benchmarks recommended 24 dBu.

http://www.aes.org/publications/standards/search.cfm?docID=44

I am going to order 2 sets of Benchmark branded XLR's for the DAC3B - HPA4 - AHB2 chain but was curious if anyone else had compared the professional grade Benchmark XLR's versus what they refer to as consumer grade XLR's?

https://benchmarkmedia.com/blogs/application_notes/balanced-vs-unbalanced-analog-interfaces

"Look for CMRR specifications on balanced inputs. "

I just posted this question to the people at Audience. They XLR cables I am currently using.

 

[llamaluv]

Thanks, I dunno why I didn't see that while browsing the settings. Can anyone explain why the RCA is so much louder than the XLR by default?

Found this. Interesting though, my XLR inputs were left untouched yet RCA was louder, when it should be equal since they're boosted automatically to be matched?

On the screenshot from the manual you previously attached, it says:

​

By default, the unbalanced inputs on the HPA4 are automatically boosted by 15.8dB so that they will match the level of the professional-grade balanced inputs.​

​

Note that that's +15.8dB, not +6dB.

So to get the resulting headphone output volumes to be the equivalent between XLR and RCA inputs (assuming that the XLR input voltage is exactly twice that of the RCAs -- ie, +6dB), the boost setting for the RCA input should be set to -10dB and the XLR boost setting left at its default of 0dB.

 

[llamaluv]

This evening I did a comparison between the XLR and RCA inputs and found them to sound remarkably similar.

I had both connections coming from the same DAC (a DAVE), and had the RCA input "boost" setting at -10dB (as described above), such that the two inputs were volume matched. And by disabling all but those two inputs in the HPA4 settings, I could alternate between the two seamlessly using the remote and essentially self-administer a blind A/B test.

On the Susvara, I could not tell the difference. Like at all. I didn't even attempt to guess which was which because they sounded so similar.

Interestingly though, on the Abyss Phi TC I could, and I actually preferred the RCA input by just a hair, at least based on how my specific system is configured. Using RCA, it sounded a little wider, slightly sweeter in the midrange, and perceptually a shade louder (even though if anything RCA should be down 0.2dB due to the 15.8dB internal offset). FWIW.

This was of course an imperfect little experiment because any DAC's XLR and RCA outputs will never be 100% identical (voltage differences aside). Plus, I don't have identical models of XLR and RCA interconnects, though they are both from the same product line (Danacable Diamond mk1 RCAs versus Danacable Diamond Reference XLRs).

Anyway, my takeaway is that the RCA inputs on the HPA4 are very, very good relative to XLR, and all things being equal, I wouldn't balk at using RCA in the slightest (and in my system, I probably will be into the future).

 

[koven]

This evening I did a comparison between the XLR and RCA inputs and found them to sound remarkably similar.

I had both connections coming from the same DAC (a DAVE), and had the RCA input "boost" setting at -10dB (as described above), such that the two inputs were volume matched. And by disabling all but those two inputs in the HPA4 settings, I could alternate between the two seamlessly using the remote and essentially self-administer a blind A/B test.

On the Susvara, I could not tell the difference. Like at all. I didn't even attempt to guess which was which because they sounded so similar.

Interestingly though, on the Abyss Phi TC I could, and I actually preferred the RCA input by just a hair, at least based on how my specific system is configured. Using RCA, it sounded a little wider, slightly sweeter in the midrange, and perceptually a shade louder (even though if anything RCA should be down 0.2dB due to the 15.8dB internal offset). FWIW.

This was of course an imperfect little experiment because any DAC's XLR and RCA outputs will never be 100% identical (voltage differences aside). Plus, I don't have identical models of XLR and RCA interconnects, though they are both from the same product line (Danacable Diamond mk1 RCAs versus Danacable Diamond Reference XLRs).

Anyway, my takeaway is that the RCA inputs on the HPA4 are very, very good relative to XLR, and all things being equal, I wouldn't balk at using RCA in the slightest (and in my system, I probably will be into the future).

Any impressions on the sound compared to your Pass amp? Are you planning to keep both SS?

 

[llamaluv]

Any impressions on the sound compared to your Pass amp? Are you planning to keep both SS?

Ah yea, I just started doing direct comparisons between the HPA4 and X150.8 with the Susvara over the last couple days.

I was initially quite taken by the HPA4's clean presentation, which I posted about earlier. The HPA4 is wider than the X150.8 on the Susvara, which is interesting. Presents details in a more accentuated, self-conscious manner. And creates the impression of sharper, quicker transients. Treble is sweeter, which I like a lot on most recordings. And probably smoother, even. I love the HPA4's treble on the Susvara. The bass, too, with the Susvara is nice and clean and "tuneful". The upper-midrange is to me a little overdone on some recordings though, especially on compressed and "bad" recordings. That can be subjective though, of course.

On the whole, I may still prefer the Pass Labs X150.8 with the Susvara. It's warmer from the lower mid-range down to but not including the sub-bass. Has a shade more oomph in the lower register generally (though I definitely wouldn't call the HPA4 "bass-lite" with the Susvara). At 93 pounds and 150 watts, I guess it had damn well better be. Has a denser, lusher sound. "Analog-like". Combined with its superior depth, all those qualities creates an enveloping kind of presentation that can be compelling in an almost opposite way to something like the HPA4. Almost like a tubes-versus-solid-state type of thing.

With the TC however, it's turned out to be a no-brainer. This was a surprise to me. I think I developed a premature prejudice against solid state with the TC, and never really liked the it on the X150.8. Anyway, I've ended up doing most of my listening with the HPA4 so far using the Abyss. It brings out all the strengths of the TC without being fatiguing. I get no sense whatsoever that it wants for more power. And it sounds appropriately relaxed when it's supposed to. Really clean, articulate bass. And again, very nice, sweet treble. The amp has made me re-evaluate my opinion of the TC in general (I think it's a better headphone now than I did pre-HPA4).

I still haven't done a ton of listening to the Utopia on the HPA4 but very much liked the couple hours I have done. Similar as with the TC, probably the most important thing I've noticed is that while being highly resolving (of course) and dynamic, it still sounds relaxed.

 

[koven]

Well said! Totally agree w/ your thoughts on HPA4+Susvara, and your reasons on ultimately preferring the Pass pairing is similar to how I feel about the Bakoon i.e. more organic and tonally richer than the HPA4. Nonetheless a bit of hair splitting as the HPA4 is incredible in it's own way, especially for under $3K!

 

[SilverEars]

I thought this amp sounded pretty ordinary, and quite pricey for such performance of sound. I don't see what the big deal is about. I've heard this type of sound in low priced amps. HD800S sounded like it does out of a typical SS out of this amp lacking bass and upper-mids with treble emphasis.

 

[koven]

I thought this amp sounded pretty ordinary, and quite pricey for such performance of sound. I don't see what the big deal is about. I've heard this type of sound in low priced amps. HD800S sounded like it does out of a typical SS out of this amp lacking bass and upper-mids with treble emphasis.

To be fair, HD800S sounds equally mediocre out of any SS amp.. It really needs some tube flavor to be enjoyable.

 

[SilverEars]

To be fair, HD800S sounds equally mediocre out of any SS amp.. It really needs some tube flavor to be enjoyable.

Yes, HD800S out of ZDS is pretty stellar, but it can sound fairly good out of BHA-1, which is also a solid-state that doesn't sound typical. Oddly, BHA-1 doesn't have solid-state characteristics like typical, but it's not like PASS amps which I found a bit warmer than my liking. Same for for EC tube amps, not really warm in a tube sense, but quite fast like solid-state, but without the usually solid-state tonality if you know what I mean. BHA-1 is a different solid-state to EC being different sounding tube amps. lol

 

[koven]

Yes, HD800S out of ZDS is pretty stellar, but it can sound fairly good out of BHA-1, which is also a solid-state that doesn't sound typical. Oddly, BHA-1 doesn't have solid-state characteristics like typical, but it's not like PASS amps which I found a bit warmer than my liking. Same for for EC amps, not really warm in a tube sense, but quite fast like solid-state, but without the usually solid-state tonality if you know what I mean.

Absolutely.. haven't tried the BHA-1 but did have the EC BW2 in the past which was quite an atypical SS sound.

 

[Tobes]

I think its fair to say that Benchmark don't design equipment to 'flavour' sound. That approach won't suit everyone's personal goals or equipment taste, but I think its a reliable baseline for broad compatibility and long term enjoyment.
FWIW, I had the BHA-1 prior to getting the HPA4 and compared them over a week or so using the Focal Utopia.
Both fine headphone amps but I heard greater clarity and transparency - more truth and realism - from the HPA4.
I also preferred the functionality and flexibility of the HPA4.

 

[MacedonianHero]

I think its fair to say that Benchmark don't design equipment to 'flavour' sound. That approach won't suit everyone's personal goals or equipment taste, but I think its a reliable baseline for broad compatibility and long term enjoyment.
FWIW, I had the BHA-1 prior to getting the HPA4 and compared them over a week or so using the Focal Utopia.
Both fine headphone amps but I heard greater clarity and transparency - more truth and realism - from the HPA4.
I also preferred the functionality and flexibility of the HPA4.

Plus, I found a "sheen" on the treble region with the BHA-1 that is not there with the HPA4.

 

[koven]

Another plus SQ aside the volume control on HPA4 is incredible and unparalleled.

 

[Pastwa]

To be fair, HD800S sounds equally mediocre out of any SS amp..

Did you try them with Bakoon? I would expect HD800 should get a very decent bass extension and heft in lower frequencies with this amplifier (much better than with HPA4) if it is any similar to its brother HPA-21.

 

[koven]

Did you try them with Bakoon? I would expect HD800 should get a very decent bass extension and heft in lower frequencies with this amplifier (much better than with HPA4) if it is any similar to its brother HPA-21.

I have not since I only recently got the Bakoon a couple weeks ago.Though HD800S is one I tend to buy then sell in a vicious repeated cycle for some reason.. so I'm sure I'll have another at some point and would be able to try with Bakoon.