[ch1n4]

  Last month, i bought one from Amazon Japan; so i think i am qualified to post my own experience and impression with this wonderful little gadget:
First, let's talk about its build quality; i think it is built like a tank with all aluminum body and polished front panel; however the four screws left on the top metal cover are eyesore but according to the owners of the original model A4, their presence may faciliate the replacement of OPAMP, which i have found is not so for A4-BL; more on that later. 
Second, about its sound qualtity: i have some highly sensitive IEMs and some high and low impedance cans to pair with my A4-BL; and they pair well; the sum up, the sound of A4-BL is very neutral, resolving and spacious, not colored, more like FOSTEX adopting a reference tuning on this one, which may displease some audiophiles who have preference for a very colored sound and find the sound of A4-BL a little boring; it is noteworthy that i have only listened to the SE and have not tried the BAL OUT, which may be more powerful and euphonic judgding from the specs (300MW BAL vs 150MW SE); having read the A4 thread, i am very intrigued to try OPAMP rolling on A4-BL but my attempts to do so failed because this required the complete disasembly of the entire metiallic enclosure, taking out of the PCB and even the removal of the potentiometer, which is very tricky; however I do have a careful look at the internal PCB layout and find it quite different from that of the original A4  because FOSTEX does adopt a TRUE balanced design on this one. First I see three NJR2114Ds and two OPA2134PAs soldered onto the right corner of the PCB with a replaceable DIP version of OPA2134PA on a DIP socket, which i think is right located at the gain stage of the PCB. In addtion, what makes me think this is a truly balanced design is that channel imbalance issue frequently found on non-balanced amps is non-existent on this one. On top of that, the new type of capacictors touted by FOSTEX in its ads are actually NICHICON FG series and I do see two or three MUSES-series capacitors.
I think what i need to do now is to find a pair of balanced headphones to see how it pairs with A4-BL; i eye for BEYER T5P 2nd GEN, but boy, what a hefty price to pay! my wallet is crying.

thanks for your impressions. Did you test it with high impedance phones? I am wondering if it could drive a Sennheiser HD 600/650 in balanced mode.
is it already available outside japan? couldn't find any reviews...

 

[lbbef]

I've been thinking of getting the HP-A4BL for quite some time.

I have the HP-A4 and use it exclusively as a DAC into my AT-HA22TUBE. I'm feeding it clean power from a linear power supply into a USB conditioner which also separates the data and power lines. And it simply sounds amazing.

But the HP-A4BL with the upgraded components as well as the ability to feed it dc power directly is tempting. Not to mention the quad rate DSD support (original HP-A4 only double rate). If they had it with a dual PCM1792A then it'll be perfect. (PCM1792A is my favorite DAC chip)

But I guess all this has to wait since I just recently upgraded the power and cables in my setup.

 

[lbbef]

That aside. There seems to be a minor mismatch in specs between the Fostex international site and Fostex JP site. The international site lists 300mW into 32ohms unbalanced. The JP site lists 150mW into 32ohms unbalanced.

 

[Villy]

B&H expects to have it available in stock by May 20th, so maybe within a month we'll have some impression and details from more responsive members. I am still interested, though it is not likely I'll make a move until I read some solid reviews. And even then it is unlikely, my current setup is pretty hard to beat but I'll keep open mind (and ears about it.

 

[Uzuzu]

 
 

 

 

 

Here the Link to the Japanese spec sheet:
 
http://www.fostex.jp/wp/wp-content/uploads/2015/12/FOSTEX_HP-A4BL_Release.pdf
 
http://www.fostex.jp/products/hp-a4bl/
 
4 pole XLR-balanced output and inside a Burr-Brown PCM1792A. I believe the rest is basically the normal HP-A4.

I believe that headphone is the TH-600 mk 2, compliment to the recent TH-900 mk 2 released with disconnectable cables. And they ditched the magnesium cups for wood.

 

[tp147]

Hello altogether,
 
has anyone experience with this amp paired with Hifiman HE400, 500, 560, 600 or Audeze LCD 2 or 3 and has the amp the capability to drive those planners proper?
I would suggest it is able to drive Fostexs own T50RP or the more expensive TH500RP, isn't it?
 
BTW: If this amp has a real symmetric design, why doesn't it have a symmetric balanced line out with XLRs?
 
Thanks & cheers
 
Thorsten

 

[Slow_aetk]

I wonder if the DAC part of it is also balanced? Which is the same as asking if the PCM1792A is a 4 channels or 2 channels?
This amp is very interesting and not expensive if it is a real and full balanced dac/amp.
 
Anybody?

 

[Villy]

I'm not aware of it being sold outside of Japan, some people had it shipped from there but I doubt many enough to have meaningful impressions, let alone experience with planars. I'm eager to hear some feedback too, and will indeed buy it once available in the states.

 

[Slow_aetk]

I'm not aware of it being sold outside of Japan, some people had it shipped from there but I doubt many enough to have meaningful impressions, let alone experience with planars. I'm eager to hear some feedback too, and will indeed buy it once available in the states.

It is available in Europe or at least in Switzerland. My preferred reseller has one in stock. To buy or not to buy...

 

[WayTooCrazy]

  It is available in Europe or at least in Switzerland. My preferred reseller has one in stock. To buy or not to buy...

Buy, test, give impressions, return if you don't like.

 

[Villy]

I have put a pre-order with B&H here in the US, at $399 - don't know what it costs in EU, but getting DSD DAC with balanced amp from Fostex at this price, in a good-looking package at this price is a no-brainer. Not to mention the potential ability to swap opamps, so yes just get it and report back.

 

[Shogster]

Is it worh it getting this version if im not going to use the balanced out? Im going to use it with the Purplehearts.

 

[tp147]

I Germany it is around 500 EUR (550 USD), but its balanced output is only for headphones, line out is only RCA unbalanced.
 
Please give us your impressions.
 
Thanks & cheers
 
Thorsten

 

[Treeko]

Hey guys is it 300mW unbalanced or balanced? And from an owners perspective how is it fairing?
Cheers in advance!

 

[chowyeung]

Excuse me. May someone confirm whether the rear RCA outputs are fixed or variable? Can HP-A4BL be used also as a volume controller for active speakers?
Thanks in advance.