Amp for HD 555/HD 595

[Chris34000]

Hi!

What amp under 150 Euros (200 USD) would you choose for the combination X-Fi Music + HD 555?

What would you choose for X-Fi + HD 595?

Chris

 

[majkel]

Portable: http://forum.mp3store.pl/index.php?s...dpost&p=190118

Belt clip is an option.

Desktop (looking for a nicer housing, bigger knob already found): http://forum.mp3store.pl/index.php?s...8&#entry216378

I have sold around ten pieces and people are happy recommending it to the others. It's been designed with companion of HD595's from the beginning. Any low and moderate impedance headphones will be happy

The second switch is output impedance booster, increasing bass on heaphones like HD595. Desktop version as in the picture + AC adaptor would be 95€ via PayPal.

 

[Chris34000]

Hi!

Thanks for your answer.
Why would you recommend your amp over this product:
http://www.presonus.com/hp4.html

for instance? I am just curious.

Chris

 

[majkel]

I haven't heard about that amp before.

I have auditioned Pro-Ject Head Box II and I honestly don't recommend it for HD595's. I made a A-B comparison to my DIY, and that amp disappointed me. Thin bass, distant soundstage, lifeless presentation and poorly balanced volume potentiometer. All that for more than 100€. You could also look at some portable amps but I haven't listened to them, either. The good ones are expensive, like from RSA, and the cheaper won't probably squeeze all the juice from the HD595's.
Coming back to HP4 - 150mW per channel is not much for a desktop device. With my desktop amp you can push 220mW per channel into 50 ohms, 345mW into 32 ohms, 460mW into 24 ohms and 690mW into 16 ohm headphones. Maximum operating voltage for the parts is the limit. You can go down with the load impedance and reach 1.5W because of the maximum posible output current.

 

[MCC]

If you can find a used headfive, it's known to be an excellent match with 595s. Hence my ownership of one.

 

[Chris34000]

Quote:

Originally Posted by majkel /img/forum/go_quote.gif Portable: http://forum.mp3store.pl/index.php?s...dpost&p=190118 Belt clip is an option. Desktop (looking for a nicer housing, bigger knob already found): http://forum.mp3store.pl/index.php?s...8&#entry216378 I have sold around ten pieces and people are happy recommending it to the others. It's been designed with companion of HD595's from the beginning. Any low and moderate impedance headphones will be happy The second switch is output impedance booster, increasing bass on heaphones like HD595. Desktop version as in the picture + AC adaptor would be 95€ via PayPal.

Do you have a site where you offer the Amp for sale? Do you ship in the EU?

 

[MaloS]

There is a Pimeta in FS forums from a guy who lives in Italy...

 

[majkel]

Quote:

Originally Posted by Chris34000 /img/forum/go_quote.gif Do you have a site where you offer the Amp for sale? Do you ship in the EU?

Yes, EU is preferred for me because no duties will apply. I'll be building the portable version for a guy in Ireland this week. I accepted his payment via PayPal today.

If you don't like the plastic housing, I could provide the Hammond 1455K1201 metal box for 20€ extra. Also, I have found nicer and bigger volume knobs to use.

Regarding PIMETA - I'm pretty curious how my amp compares to this, because for me the PIMETA circuit has got some bugs causing it sounds worse than it could. Of course, it will never exceed the limit of the AD8620 sound signature. Also the belief of class A improving sound of modern op-amps is an error. I've tried biasing many op-amps into class A and the changes were from slight to none. The most responsive was AD825 but it's disputable the op-amp's sound signature improved. On the AD8620 the change is smaller.
The ground channel needs redesign - it's capable of 250mA while the channels need 250mA each, so they can actually sink or source around half the current they are capable of because the ground channel limits it to 250mA total. My amp can sink/source full range of 350mA per channel without the limit because the ground channel provides 0.7~1A, depending on the version. Another inconsistence - if channels are biased into class A, why AD8610 in the ground channel buffer circuit is not? The voltage swing is much smaller here than on the channels so the advantage should be even more audible.