[qusp]

most modern opamps have no need to be class A, modifying a truly modern opamp for class A operation (as easy as a couple of resistors) will often make the sound worse not better. dont buy into catch phrases without knowing why.

 

[wuwhere]

I really don't understand why someone would want a class-A HP amp. I used to own a class-A mono-block pair of amps for a full range ribbon speakers but for HP application?

 

[Currawong]

Quote:

What does inefficient and practical have to do with getting the best sound possible? My home amps have that class A sound. Why would anyone want to go on the road with anything less.  That is of course unless they have never heard it.

 
Because I'd rather not carry a lot of batteries or a huge amp around if I'm going portable.

 

 

[qusp]

Quote:

I really don't understand why someone would want a class-A HP amp. I used to own a class-A mono-block pair of amps for a full range ribbon speakers but for HP application?

didnt you used to have the class a topkit for D10 from hiflight? with some older opamps it works quite well, but most modern chips already runin a or ab stock

 

[wuwhere]

Quote:

didnt you used to have the class a topkit for D10 from hiflight? with some older opamps it works quite well, but most modern chips already runin a or ab stock

EL8201 as buffers for the D10 with AD744 output bypassed class A opamps. I actually like this combo, very warm-sounding.

 

[grokit]

The battery life seems good, good power too:
 
[size=x-small][size=x-small]"DRIVE ANY HEADPHONE IN THE WORLD FROM 16Ω to 600Ω[/size][/size]
[size=x-small][size=x-small]RECHARGABLE 9V Li-ion BATTERY WITH HIGH PERFORMANCE FETURES MADE BY MICROSHAR(MS600)

UP TO 12 HOURS CONTINUES USE BATTERY LIFE

ONLY 2 TO 3 HOURS CHARGING TIME[/size][/size]
[size=x-small][size=x-small]SWITCHING (90 TO 240VAC) WALL CHARGER HIGH QUALITY MADE BY MICROSHAR[/size][/size]
[size=x-small][size=x-small]IT POSIBLE FOR USE AS A 9V PORTABLE HEADPHONE AMP OR 12V DESK TOP HEADPHONE AMP"[/size][/size]
[size=x-small][size=x-small]And the kicker:[/size][/size]
[size=x-small][size=x-small]"LABORATORY HAND MADE IN THE USA"[/size][/size]

 

[Sumflow]

Why do tube amps sound different?

 

[shigzeo]

More distortion is the main reason. Tubes and op-amps/transistors are very different animals. 

 

[Sumflow]

A hundred times, a hundred watts per channel, is one thing.  But a hundred times what it takes to push in-ear earphones should be tiny in comparison.

Quote:

Quote:Originally Posted by Currawong   Because I'd rather not carry a lot of batteries or a huge amp around if I'm going portable.

What do you need impedance: 56 ohms? 100 times whatever it is can’t be much larger than a ipod. How does that constant current work?

 

[Currawong]

 
Quote:

Why do tube amps sound different?

They don't necessarily.

 

[shigzeo]

^^ indeed - from eachother, they don't have to, but when compared to solid state amps, they generally gain their 'smoothness' from greater levels of distortion.

 

[Xan7hos]

I believe that the HiSound Amp3 mp3 player/amp combo is supposedly Class A. I can definitely tell you that it doesn't offer a lot of headroom so it can drive most IEMS and low imp headphones (32-60 ohms) but it might not get as loud as one would like. Not to mention the hiss on the unit is distracting at times

 

[shigzeo]

The AMP3 certainly doesn't drive my iems very well: closed in stereo and loads of hiss, not to mention the somewhat noticeable bass roll off: far from good with earphones. It is comfortable with 100Ω and more. 

 

[justin w.]

Quote:

Thank you I did not know until now that the uAMP109G2 was a class A amp. 

  They post specs like class A amps do.. I will look into it.  THD+N ≤ 0.00003% Made in USA.    Thanks..
Quote:

What does inefficient and practical have to do with getting the best sound possible? My home amps have that class A sound. Why would anyone want to go on the road with anything less.  That is of course unless they have never heard it.

There are too many zeros on that THD+N.  It's physically impossible. 

 

[shigzeo]

^^ indeed!