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Need help building an amplifier-headphone adapter

Hello

I have an integrated amplifier (12W) that does not have a headphone output and I want to find a way to listen via headphones.

The easy solution would be to find a device like the ASL UHC. But I have not managed to find one for sale in Europe.

http://www.divertech.com/asluhcsignature.html

Now I want to try to build one myself :) Could be a nice project and will add a nice feature to my amplifier.

Does anyone here have experience building such a device as the ASL UHC? Are there any kits or schematics available?

Thanks for any advice.
indiesverige
czarivey
5,946 posts
 
You may do as Yogiboy did with directly coupled output stage amplifier. That will work if you have relatively high impedance headphones. If you don't, you won't be able to control the volume correctly and will have a chance of blowing either your ears or headphones whichever comes first.
If you have an output transformer in your amp, you'll need to find another transformer to match impedance of your headphones.
yogiboy's avatar
yogiboy
5,656 posts
 
Czaivey,Won't your preamp control the volume just like it does with speakers?
zd542
5,339 posts
 
"If you have an output transformer in your amp, you'll need to find another transformer to match impedance of your headphones.
Czarivey (Threads | Answers | This Thread)

02-18-14: Yogiboy
Czaivey,Won't your preamp control the volume just like it does with speakers?"

I think he means having a situation where a very small change on your volume knob gives a very big increase/decrease in volume. Its very hard to control when that happens.
indiesverige OP
10 posts
 
My amp is a Shindo Apetite.

How would I find out if this has an output transformer and what its impedance would be?
zd542
5,339 posts
 
"How would I find out if this has an output transformer and what its impedance would be?"

Try to pick it up. If its really heavy, then yes, it has an output transformer. As far as impedance goes, it should be labelled by the speaker terminals. You could also check your owners manual. All that info is listed.
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