HeadAmp for DT770 600Ohm?

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Hello, I've been enjoying my DT770 Premium 600ohm edition for a while now.
I've been powering it from my Asus Xonar Essence ST card and I've started to notice that the bass is a bit weak/low compared to what people say and most reviews.

Thats why I though it would be time to get a dedicated amplifier instead of the built-in amplifier in the xonar.
I was thinking of the Fiio E9, though I have no idea how it performs or if I could throw in a Alps Blue Velvet to slightly improve the sound.

Do you have any suggestions? :)

Budget: 150-200$
Specs:
Needs to power 600ohm headphones without a problem.
SolidState amp would be prefered.
Stereo.
No background noise. (Xonar essence amp is 100% silent)
 
The O2 in this section would work given the higher voltages your 600R cans need. The one user review done so far from an early PCB says it is silent:

http://www.diyaudio.com/forums/headphone-systems/193977-objective2-o2-headphone-amp-diy-project.html

http://nwavguy.blogspot.com/2011/08/o2-summary.html

On AC you require somewhere around 7Vrms / 600R = 11.7mA output, from the around 140mA per channel it can push, so no problem there. You would get up to around (7Vrms ^ 2) / 600R = 81.7 mW per channel output, which is a good match to the 100mW max per channel rating of the DT770s.

On batteries you need somewhere around 4.5Vrms / 600R = 7.5mA and would get around (4.5 ^ 2) / 600R = 33.8mW output.

If his future desktop version winds up allowing for higher rail voltages, like say +/-15Vdc, that would give you somewhere around (9.5Vrms ^ 2 ) / 600R = 150mW per channel, but that would be over the max rating of the headphones - and probably much to loud anyway.

The group buy on the PCBs hasn't closed yet and is just now taking payments if you want to give it a try. :) I just paid around $8 USD for 2 PC boards and the rest of the parts (minus the case or AC adaptor) apparently clock in somewhere around $20 plus shipping from Mouser. With case, batteries, adaptor and front panels it apparently adds up to around $100. Someone is offering a build service too in the thread if you don't want to DIY.

 
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Thanks. :)
Though I was hoping for a completed amp and not DIY.

Since I live in Norway, I'll have to pay alot more than you have to in the US.
Normally 30-40% depending on the item.

Also, there aren't any shops around here that sells electronic parts..



I was lucky with getting tubes and a new vol-pot for my "Xiang Sheng 708B" on Ebay.. Sadly the sound was much better on the Xonar so it was a waste of time and money.
(I bought recommended tubes and a Alps Blue velvet for the amp.)
 
Mouser has Norway as a country selection, but the prices are probably higher:

Mouser Electronics - Electronic Component Distributor

The 7th person in that group buy is also from Norway along with one other, but I'm not sure if they are using Farnell or Mouser Norway. The BOM has Farnell numbers listed too for much of it. Farnell might have an issue with only shipping to businesses in Norway too, if I'm remembering right. There is a way around that though using Borderlinx.com to ship to a US address from US Mouser then DHL to any other country.

The person offering a build service is this fellow (Mr Slim), who apparently is in Canada. He may be willing to ship to other countries - might be worth a post or PM to him if you want.

http://www.diyaudio.com/forums/head...-headphone-amp-diy-project-5.html#post2686121

Also the designer of the O2 did an E9 review here, FWIW:

NwAvGuy: FiiO E9 Headphone Amp
 
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Thanks, I'll look into it. :)
The reason I was thinking of moving to a completed amplifier instead of DIY is because the "Xiang Sheng" didn't perform very well and cost me alot.

Also, I barely have any time for a DIY project.
I have school from 6AM to 5PM, homework and addition to that I have to study for a "Computer and Electronics Certificate" which will probably take me 9-13 months. :(
+ Work at Saturdays.

Thanks for the advice though.
I'll see if its possible.. If not.. I'll have to spend some money on a non-DIY amp.
 
I forgot one. The fellow running that group buy for the PC boards owns an audio company in the UK and he is selling them. Looks like he has re-branded it to the EHP-02 and is doing pre-orders:

EHP-O2 - Epiphany Acoustics

The person who designed the amp released the design as open source, so any company can build and sell it with no license fee. The UK would probably be a lot less shipping charges!

All the other headamps I know well are DIY projects. :) I'm sure you will get a bunch more posts with some good suggestions for non-DIY amps that would work well with the 600 ohm headphones.
 
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