Fostex HP-A4BL (the A4 with balanced output)

[HungryPanda]

Just received this wonderful little amp. Got to listen to my LCD-X's balanced for the first time. I have now ordered a balanced cable for my HD650's

 

[KingFiercer]

Has anyone tried to change op amp? Does this make sense here?

 

[Dartin Bout]

Someone earlier in this thread opened this unit up and confirmed there was balanced circuitry but they never came back with the outcome of their investigation. The internals do seem to be quite updat date. I am interested in op amp rolling because I wnet from a set of LM4562 to Muse02 on my Auzentech card and really like the change. There are the Burson 

Supreme Sound Opamp V5

 
 

that I think would fit if there are dip connectors..​

 

[KingFiercer]

So changing OPA2134 will only affect line output?
I tried to listen HP-A4 via USB, the sound was a bit harsher and thinner than I prefer.
Has anyone compared A4 and A4BL? Some owners wrote that A4BL has more bass and power in sound.

 

[obsidyen]

So what is the opamp in this unit, and is it a good one? Is it not possible to change it easily like the first model?

 

[Sayed2020]

For those looking for an external upgrade, I can confirm the iFi iPower 12 volt 1.8 amp power supply works great with this balanced DAC amplifier : )

 

[davidmthekidd]

Anyone else having issue with this dac/amp on windows 10?

 

[hanouk]

I have the regular HP-A4 (not BL), received today, I got no sound (even with win10 recognizing it and after having installed the driver). I tried to update the firmware from 1.01 to 1.10 and now it's even worse, my hp-a4 has the 44.1k led flashing red constantly.

Any idea ?

 

[HungryPanda]

Fostex recommend not using with W10

 

[KingFiercer]

When using optical toslink there is no annoying problems with sound latency in videos and games, which I have with USB connection on Win7 x64. It's good solution for Win10 I suppose.

 

[davidmthekidd]

This thing rocks.

So I ended up purchasing this little baby out of sheer curiosity. I needed a bedside Amp/Dac set up, and as touched upon above, was contemplating between another O2+ODAC, a JDS The Element, Schiit Jotunheim, and this Fostex HP-A4BL. The Fostex was the cheapest to include a balanced XLR output on top of an optical out (for connecting to the PS4 Pro/PS4 or Xbox One), so I thought why not. You can find it from between £360 and £375, which makes it fairly solid value. It's only $350 in the US, which is even better value for money.

The Schiit Jotunheim was the next cheapest attractive alternative to include balanced out, but doesn't have an optical in, and is also £90 more expensive at todays exchange rate (including shipping), but not including taxes (a possible 20% VAT on top). Granted specs wise it's a lot more powerful.

Initial impressions.

After some brief testing with the HP-A4BL yesterday, I cannot believe this Dac/Amp combo is not more popular. Why this thread is only on page 5, whilst the Jotunheim's is on page 177, I'm not quite sure.

In terms of sound quality, it is every bit as competent as the Violectric V200+Rein Audio X-DAC, the X-DAC+O2 and the O2+ODAC. There are miniscule differences between some of them, depending on the connection type and combination set up used, but it's generally a case of very minor, oft insignificant, other times nonexistent one's that don't massively sway things either way.

Importance of volume matched A/B'ing, including blind.

Essentially the HP-A4BL on it's own (internal DAC and amp) via USB, sounds exactly the same as the Rein Audio X-DAC + Objective 2 combo via Optical, which is one of my fave combinations that I own or have tested (including versus other much more expensive gear I either own, or no longer own). And for the record, I A/B blind tested multiple times (with the help of my wife), and volume matched via mic readings before hand. Before I did that, placebo was well and truly kicking in (including when comparing the two different digital filter modes).

The mind is a powerful thing. Trust me, until you've persistently A/B tested with extreme analytical concentration, with as close to perfectly volume matched set up's as possible, do not think you can accurately gauge sonic differences. Simply put, you can't. Even a 5-10% difference in volume between set ups can make all the difference.

USB vs Optical?

Another good thing about the HP-A4BL is that out of my Macbook Pro Retina, just as with my X-DAC, there does seem to be a very slight difference in signature between Optical and USB (based on rudimentary preliminary testing), which is good because it allows me to switch between neutral and ever so slightly warm.

Power.

One slight negative however is that the HP-A4BL doesn't quite have the same amount of power as my O2, nor my Violectric V200. That said, it still has more than enough for my use, and is sufficient enough to power the MDR-Z1R's, HD800's and T1's. With the Z1R's I don't go need to beyond half volume on low gain, and with the other two, I don't even get to half way on the volume knob in high gain, In other words, there's more than enough juice for real world use.

For now.

I'll go in to more detail in my subsequent review, including comparisons with all the different combos I've compared, but for now I'd like to do more tests, including more blind A/B one's. I haven't even gotten around to testing the balanced out yet, which I'm looking forward to.

In conclusion ahead of my review though, just go buy this amp/dac. For the money you simply cannot go wrong.

Pic.

Here's a cheeky mobile snap. Apologies for the ugly white cardboard box, just waiting for my new Oak bedside draw to be delivered!

How's that Combination of the MDR-Z1R with the Fostex HP-A4BL??? I Have the A4BL already, I would like to know how does it pair with the Z1R or even the Z7? Can it produce frequency's under 20Hz?

 

[Naim.F.C]

How's that Combination of the MDR-Z1R with the Fostex HP-A4BL??? I Have the A4BL already, I would like to know how does it pair with the Z1R or even the Z7? Can it produce frequency's under 20Hz?

It pairs fantastically. I use it via USB out as that sounds ever so slightly cleaner and crisper to me than optical which I felt was a touch warmer (could just be placebo). Sonically it pushes my Z1R's and other headphones (HD800, HD800S, LCD-3, T1.1 etc) as well as anything else I've tried, at least at the sort of volume levels I listen to anyway. Never had to push the volume knob more than halfway either. With the German cans I do use the gain mode though.

 

[HungryPanda]

I have to agree this little powerhouse drives everything I have with ease

 

[davidmthekidd]

It pairs fantastically. I use it via USB out as that sounds ever so slightly cleaner and crisper to me than optical which I felt was a touch warmer (could just be placebo). Sonically it pushes my Z1R's and other headphones (HD800, HD800S, LCD-3, T1.1 etc) as well as anything else I've tried, at least at the sort of volume levels I listen to anyway. Never had to push the volume knob more than halfway either. With the German cans I do use the gain mode though.

Cool, Adorama had the Audeze LCD-2 on sale today for $650 New, I couldn't let that get away for such price, got em. Also, I went got the Audeze Balanced XLR cables for it aswell, the HP-A4BL drives the LCD-2 Like a champ, specially Balanced, I can barely push the Volume noob to 12 O'Clock, loud as heck. Great Dac/Amp!

 

[davidmthekidd]

It pairs fantastically. I use it via USB out as that sounds ever so slightly cleaner and crisper to me than optical which I felt was a touch warmer (could just be placebo). Sonically it pushes my Z1R's and other headphones (HD800, HD800S, LCD-3, T1.1 etc) as well as anything else I've tried, at least at the sort of volume levels I listen to anyway. Never had to push the volume knob more than halfway either. With the German cans I do use the gain mode though.

Perfect, So would you recommend that combination? you dont mind running them via 1/4" instead of Balanced. Last question, Amazon has the international version for $1,599, is it a good idea to get that?