Review and Measurements of Benchmark HPA4 Headphone Amp/Pre

[RichB]

Is anyone using Logitech harmony remote for the HPA4 or LA4?
I couldn't find them from harmony device list.

I am using a Pronto remote. The LA4 mute, volume up/down, and input up/down are the codes used for the DAC3. Try using that device. As I have mentioned before, the direct input commands do not work unless used with a companion DAC2/DAC3. Benchmark,, Benchmark, Bueller...

- Rich

 

[FourT6and2]

Have put about 18 hours on the HPA4 and THX 789 now. Using DAC3-B. They sound great. No complaints other than price. 789 and HPA4 sound very close. 789 is sliiiiightly brighter/snappier on the attack of bass and drums. HPA4 is sliiiiiightly thicker/deeper overall. But this is me really nitpicking something. Features aside (I don't need touch screen or multiple inputs/outputs or a preamp or all that junk), they both sound equally amazing so it's hard to justify $3,000 when the 789 is only $400. I've got about 3.5 weeks to make a decision and will be doing more comparisons for sure. Benchmark is certainly built better.

 

[doug]

Keep listening to the HP4. That’s been my downfall with all of the Benchmark gear that I own. The shit just grows on you, and when you go back to other gear, to me, there was always something ... missing.

 

[xema]

When I had the audition of the HPA4, I found its lineout sounds as perfect as its measurements, but its headphone output is not as perfect as the lineout.
Its headphone output is quite good for the most part, but the sound stage is strangly narrow and higher above my forehead, which I had almost never met in other headamps.

Well, I'm so satisfied by its preamp, so I bought a LA4 instead.

 

[Darkweb]

Man Benchmark makes some ugly ass gear. Who could think that adding a Walmart credit card reader touchscreen to the front of gear looks good? It not only looks horrible, but dates your product the second it comes out.

 

[BYRTT]

Had a bad day or what @Darkweb looking for a battlefield, imagine this machine probably looks and perform exactly as creator wanted it to and anybody not satisfyed that spirit can move on and buy some other gear that suits their mood and taste.

 

[Lac013]

Look through his history, he just adds negativity throughout different threads

 

[Russ_L]

The HPA4 has 4 analog inputs, meaning a maximum of 3 button presses to change to your desired analog source. Are a couple of extra button presses such a big deal if you watch a movie? It isn't for me, but then I primarily use the HPA4 for listening to music.

Single or divorced?

Russ

 

[RichB]

Single or divorced?

Russ

I don't have AI macro's on my remote.

- Rich

 

[Russ_L]

The missing discrete input and HT bypass is the reason why I still didn't pull my trigger on LA4....
Sigh...

?? LA4 has HT bypass if so desired. Any input can be set to a fixed value (unity gain in this case) in the setup menu. Now if only your prepro could trigger that input ala Wyred for Sound STP-SE. RichB missed that one.

Russ

 

[tobes]

Single or divorced?

Russ

Haha. Married 24yrs actually. My wife never uses the system in my music room.

 

[anmpr1]

Haha. Married 24yrs actually. My wife never uses the system in my music room.

Hi Fi has always been a male thing. Maybe a few outliers. I use Benchmark electronics and bigger than nature ever intended loudspeakers in the living room, but waifu would rather listen to her media over a Galaxy Note. I don't even think she recognizes the difference between the two systems--only the Note is easier for her to navigate--she can walk around the house with it. Talk to virtual friends in real time, and leave instant messages. Watch stuff on a little screen. Benchmark needs a WeChat function. LOL

 

[jruser]

If you measure the 2 Vrms RCA outputs, you will find that the noise is 15.7 dB lower than that of the professional XLR balanced outputs. The noise on the RCA outputs is 0.31 uV at unity gain and 0.18 uV at minimum gain (-112 dB). The SNR is identical on both interfaces, but it is very difficult to find RCA inputs that have a 0.31 uV EIN (equivalent input noise). Low noise systems need to be built with professional-grade balanced interfaces. High-voltage professional balanced interfaces make it much easier to achieve an excellent SNR (at the system level).

This information contradicts what is published in the manual. The manual lists <8uV for the unbalanced outputs, with a SNR of only 108db. I'm thinking about purchasing one of these, but I'd be using unbalanced outputs. That listed 108db SNR for unbalanced isn't too impressive and I really don't understand why it is so much worse than the 135db of the balanced outputs.

 

[Spocko]

This information contradicts what is published in the manual. The manual lists <8uV for the unbalanced outputs, with a SNR of only 108db. I'm thinking about purchasing one of these, but I'd be using unbalanced outputs. That listed 108db SNR for unbalanced isn't too impressive and I really don't understand why it is so much worse than the 135db of the balanced outputs.

You can always look to the Schiit Freya S, which was very well measured on ASR. Best bang for the buck preamp.

 

[ShiZo]

Wait a second, hpa4 unbalanced is 108 snr?

Looks like the a90 might beat it now also?

I still love mine though.

 

[anmpr1]

This information contradicts what is published in the manual. The manual lists <8uV for the unbalanced outputs, with a SNR of only 108db. I'm thinking about purchasing one of these, but I'd be using unbalanced outputs....

Benchmark always advises using balanced connections. It makes no sense to buy this and not use it to its full capability. You'd be better off with something else. To use an automotive analogy, would you purchase a 911 Turbo S and fill the tank with generic regular at the corner Food 'n Fuel?

From the manual...

Connecting Other Audio Components: When possible, use balanced interfaces to connect the primary devices in your system. Balanced interfaces offer significant performance advantages due to the differential signals and higher voltage levels. In most cases, balanced interfaces will reduce noise in your system.

 

[jruser]

This information contradicts what is published in the manual. The manual lists <8uV for the unbalanced outputs, with a SNR of only 108db. I'm thinking about purchasing one of these, but I'd be using unbalanced outputs. That listed 108db SNR for unbalanced isn't too impressive and I really don't understand why it is so much worse than the 135db of the balanced outputs.

FYI to everyone. I emailed Benchmark and John replied with this:

"The manual shows an A-Weighted SNR of 116 dB relative to a 2V rms output. The output can deliver 4 V rms which is 6 dB higher. This gives an A-weighted SNR of 122 dB. The measurements in the manual were made with an Audio Precision AP2722. We now have an Audio Precision APX555 which has lower EIN. The post on the forum was made after measuring a production unit with the APX555. We probably need to update the manual. The specifications in the manual are overly conservative.

Please note that there are almost no balanced inputs that have a low enough EIN to preserve the SNR that the HPA4 RCA outputs deliver, so the discussion is somewhat academic. Balanced interconnects are the only way to go."

 

[Spocko]

FYI to everyone. I emailed Benchmark and John replied with this:

"The manual shows an A-Weighted SNR of 116 dB relative to a 2V rms output. The output can deliver 4 V rms which is 6 dB higher. This gives an A-weighted SNR of 122 dB. The measurements in the manual were made with an Audio Precision AP2722. We now have an Audio Precision APX555 which has lower EIN. The post on the forum was made after measuring a production unit with the APX555. We probably need to update the manual. The specifications in the manual are overly conservative.

Please note that there are almost no balanced inputs that have a low enough EIN to preserve the SNR that the HPA4 RCA outputs deliver, so the discussion is somewhat academic. Balanced interconnects are the only way to go."

Is it safe to conclude that in terms of the lowest measurable noise floor, the most accessible "end game" stack is Benchmark LA4/HPA4 + AHB2?

 

[jruser]

Is it safe to conclude that in terms of the lowest measurable noise floor, the most accessible "end game" stack is Benchmark LA4/HPA4 + AHB2?

That's my general feeling.

They need to make a phono pre to complete the system.

 

[RichB]

That's my general feeling.

They need to make a phono pre to complete the system.

For a Phono , this is truly overkill (I like overkill)

- Rich