[estreeter]

Not sure if this has been pointed out previously, but the stated prices on the website and at hifiheadphones UK seem to include VAT - those of us who live outside the UK pay less. Long story short, to have the uHA-120 (with optional Vishay pot) delivered to my door here in Oz has cost me the princely sum of 305 AUD. What I had previously disregarded as an 'expensive' amp now slots neatly in just above the iBasso D12 (about $290 delivered) and several of Ray's amps (mid 350s delivered), and well below the Stepdance at $399 locally.
 
Its nice to be pleasantly surprised by the total cost of a portable amp. Rare, but nice.
 
 

 

[i_djoel2000]

Quote:

Not sure if this has been pointed out previously, but the stated prices on the website and at hifiheadphones UK seem to include VAT - those of us who live outside the UK pay less. Long story short, to have the uHA-120 (with optional Vishay pot) delivered to my door here in Oz has cost me the princely sum of 305 AUD. What I had previously disregarded as an 'expensive' amp now slots neatly in just above the iBasso D12 (about $290 delivered) and several of Ray's amps (mid 350s delivered), and well below the Stepdance at $399 locally.
 
Its nice to be pleasantly surprised by the total cost of a portable amp. Rare, but nice.
 
 

hi estreeter, is uha120 using the same case as in amb mini3? they look similar to me..
 
and, anybody noticed significant difference of upgrading the volume pot to vishay p11?
 

 

[Jazzyfi]

Hey b0ck3n, did you get your uHA-120 already? Did you ask Justin to lower the gain to match the ES5? Any tweaks regarding output impedance?
 
Quote:

I'm in contact with Justin, working on some tweaks to best suit use with my Westone ES5. The guy is an absolute gem, wonderful to deal with and has really gone out of his way to accomodate my needs. I'm planning on getting an orthodynamic in the near future and might just get a second uHA-120 to run it balanced

 

 

[b0ck3n]

I had to jump ship on the uHA-120. Justin was kind enough to try some tweaks that he thought of offering as a standard mod, which involved cutting gain in half and lowering output impedance to 1.1 Ohm.

 
Quote:

Hey b0ck3n, did you get your uHA-120 already? Did you ask Justin to lower the gain to match the ES5? Any tweaks regarding output impedance?
 


 

 

 

[Jazzyfi]

I hope that lowering the output impedance won't give any hiss to ES5. iQube has crazy low output impedance of 0.1 ohm to 1.5 ohm at 20KHz but the disadvantage is the white noise (hiss).
Let me know how do you like it once you get it. I might order it as well to pair it with my upcoming SE5 and FX700.
 
Quote:

I had to jump ship on the uHA-120. Justin was kind enough to try some tweaks that he thought of offering as a standard mod, which involved cutting gain in half and lowering output impedance to 1.1 Ohm.

 


 

 

 

[b0ck3n]

He managed to lower output impedance without use of any resistors, so it shouldn't affect the noise floor in any way but rather just limit the effect on frequency response. It did however cause instability under some circumstances, which would waive warranty.

 

[Jazzyfi]

Hmm.. might have something to do with low battery voltage.. or does it have something to do with fast rising edge? Then it might be easily solved by extra caps in the feedback loop.. But I'm guessing too much

. I'll just wait for your impression.

 

[Jonasklam]

i'm really interested in the amp, but what is the point of the vishay p11?
I don't get it.
 
 

 

[estreeter]

Quote:

i'm really interested in the amp, but what is the point of the vishay p11?
I don't get it.
 
 

Which part dont you get ? A better potentiometer theoretically equals better volume control, and thats particularly important for people who own sensitive IEMs. I'm sure the more technically minded can give a better explanation, but thats my take on it.
 
Anyway, mine just arrived, complete with the aforementioned P11 'upgrade'. Nano in one end and KSC-75s out the other, I'll just leave it to run throughout the work day and start listening  tonight.
 
To the guys at HiFiHeadphones UK, thanks for your efforts, but that seems like a hell of a lot of packing for such a tiny amp. When I first saw the box, I had to wonder if you had accidentally sent me something else (!) but somewhere in the bubble wrap there was a small white box with an even smaller amp inside. Very attractve casework lives up to the photos on the website.
 
I have taken some photos to give people an idea of the size, but the thickness relative to the slimline amp will be the big sticking point for many - personally, anything smaller than the D4/P4 seems tiny by comparison. Will post the photos tonight.
 
 
 

 

[frenchbat]

Congrats Estreeter ! Glad the first impression is the right one for you. I'm waiting for my AHA today too, should be the same here.

 

[Jonasklam]

Quote:

Which part dont you get ? A better potentiometer theoretically equals better volume control, and thats particularly important for people who own sensitive IEMs. I'm sure the more technically minded can give a better explanation, but thats my take on it.
 
Anyway, mine just arrived, complete with the aforementioned P11 'upgrade'. Nano in one end and KSC-75s out the other, I'll just leave it to run throughout the work day and start listening  tonight.
 
To the guys at HiFiHeadphones UK, thanks for your efforts, but that seems like a hell of a lot of packing for such a tiny amp. When I first saw the box, I had to wonder if you had accidentally sent me something else (!) but somewhere in the bubble wrap there was a small white box with an even smaller amp inside. Very attractve casework lives up to the photos on the website.
 
I have taken some photos to give people an idea of the size, but the thickness relative to the slimline amp will be the big sticking point for many - personally, anything smaller than the D4/P4 seems tiny by comparison. Will post the photos tonight.
 

Thanks for the explainaination. But seriously, how hard can it be to control volue, you turn and it goes up or down. I'm not trying to be arrogant, just trying to understand and learn.
Maybe the vishay p11 = equals more positions on the volue pot? For eksample, the normal pot could have 30 "positions" where the vishay have 45 "positions" giving you better control over the sound? Is that how it works?
 
Also, I read on headfonia that the AHA-120 had a small channel imbalace issue at low level, but disappeared at listening level. And since the AHA-120 uses the vishay as well, i figured it might be due to that? I may be waaay off here?
 
Anyway, can you check on your amp, when you have the time, if there any imbalances between left and right channel at very low levels?
It is becuase I normally listen to music at very low levels and this statement from headfonia concerns me a bit.
 
Anyway, congrads on your amp! I hope you find it awesome
 

 

[frenchbat]

With sensitive IEM you may get some channel imbalance at low listening level, that's why a quality pot is necessary. Vishay is such a quality pot, or you can also get a digital controlled pot like on the Pico Slim.

 

[estreeter]

I wouldnt spend too much time worrying about anything Mike writes on Headfonia, but by the same token I dont think the AHA-120, a full class A amp, is aimed at the owners of sensitive IEMs, even if Mike used a couple of pairs of earphones in his review. Personally, I would be a lot happier if Justin could make the difference between his amps more instantly recognisable - I would have called the Class A amp the 'AHA-160' or 'Megatron' : anything to differentiate it from its considerably smaller sibling.
 
In my case, the most sensitive IEM I own just isnt going to be close to the high end kit that people report problems with 'hiss', and I have never been particularly worried by that anyway. The amp would need to have a particularly obvious problem for me to complain about that, but others here seem extremely sensitive to any hiss at any volume level.
 
Seriously, if you are intent on listening at very low volumes, I suspect one of the slimline amps from Todd or Justin W might be a better fit than a Class A design which is throwing away a milliWatt for every 2mW it generates - happy to hear otherwise.

 

[estreeter]

The photo, as promised - more photos coming later as I put my review/comparison together. I believe it is both narrower and shorter than the uHA-4 - hardly the Goliath that some seem to think from the website photos:
 

 

[kaushama]

cool stuff! What is the player next to it? HOw does it sound?