[Sathimas]

Hello,

since my SOHA is now finished (only buffers are to come ...) and university
starts in about one week I need something to look forward to in my next
holidays to get over the next term without going crazy

Something I can brood about in the evening

First of all - the Headphone Amp should be something really neutral this time.
Dead flat frequency response as far as possible. My phones are Beyerdynamic DT880.
I'd like to be able beetween coloured (SOHA) and uncoloured sound, if you know what I mean.

My total budget (including case etc.) is $200 max.

Now to the maybe more difficult part:
The Headphone Amp should have a integrated PreAmp, so that I'm able to connect an amplifier or active speakers to it.
I know that some Amps offer this function, but I havn't heard about a DIY-Amp with that feature.

I don't know much about preamps and HiFi electronics in general, so please tell me if it's not possible to realise my idea for this budget in good quality.
I think it would be best if the PreAmp used the same circuit like the headphone amp, due to the quality of the amplification?
But I'm quite sure that it will not be enough to connect some RCA-out-connectors parallel to the headphone out.

Hopefully this will be possible, in real case of need I'd be willing to spend some more money.

Thank you for any suggestions

Sathimas

 

[kvant]

Quote:

Originally Posted by Sathimas /img/forum/go_quote.gif But I'm quite sure that it will not be enough to connect some RCA-out-connectors parallel to the headphone out.

I think that it can actually be as simple as that. For example, the Pete Millett's paper has a title "Build a Low-Voltage Tube Hybrid Headphone/Line Amp" and the preamp out is precisely just parallel to the headphone out. The GS-1 of Headamp is likely to do the same thing.

My understanding is that once you have a headphone amp, it is all you need for a preamp application. Even more than that, since the preamp does not need to be capable of outputting as much current as headphone amp (the input impedance of power amps is much larger than impedance of Grados).

You can try your SOHA as a preamp and see how it goes. Just power on the SOHA first and the power amp afterwards so that a thump does not surprise you unprepared. (I don't know for sure how SOHA behaves on turn on, but it is always better be careful.)

 

[Sathimas]

Well - it's really cool that it's so easy

So - what Headphone Amp would be suitable for me?
I thought about the M3 which costs about 140$ but has no power supply included.
What would a fitting power supply cost? With the M3 I'll definitely blow my budget ... but who cares, thats what I'm working for

Maybe somebody has any better or additional idea?

 

[Jam_Master_J]

Dynalo and PPA are both pretty neutral and in that price range.

 

[Sathimas]

I think I'll stick with the M³ because its simple to get a full kit.
Also because of the excellent documentation on the website.

Does anybody know somebody who sells a kit of the sigma11 psu?

 

[FallenAngel]

Quote:

Originally Posted by Sathimas /img/forum/go_quote.gif I think I'll stick with the M³ because its simple to get a full kit. Also because of the excellent documentation on the website. Does anybody know somebody who sells a kit of the sigma11 psu?

You can always just build a tread, it's easier, smaller and easy to DIY on breadboard or buy Tangent's great little kit for only $17.

 

[Pars]

Quote:

Originally Posted by Sathimas /img/forum/go_quote.gif I think I'll stick with the M³ because its simple to get a full kit. Also because of the excellent documentation on the website. Does anybody know somebody who sells a kit of the sigma11 psu?

You might contact jrossel as he does offer a sigma22 kit as well as an M3 kit (at least he used to have the M3).

The dynalo is another good choice, but might be slightly bright with DT880s. If you could swing a B22, that would be another great way to go.

For preamp duty, don't forget things like muting (preferably switchable, and your speakers will thank you

) and input switching.

 

[Sathimas]

Jeff was the next person I wanted to contact - I already bought my SOHA- Kit from him.
The B22 is definitely out of my price range, at least for a headphone amp.
"Bright" is a word I don't like

The DT880 is quite sensible in this way.
With my first Amp, it was very bright, with the standard SOHA it became better and with the GE6680 I now have it's perfect.

The muting delay is already planned and a source selector too.
This amp will be kind of an future-proof investment, that's why I start
to plan so early. Just want to have enough time to think about it.

Today morning something else came to my mind.
At the moment I'm using a Onkyo 674 AVR and Wharfedale Evolution Speakers as my surround setup.
Some time in the future I'd like to buy some studio monitors as stereo-speakers since the Evo10 doesn't
have enough punch an I simply don't get a satisfying result using a 2.1 setup.

The problem is that the 674 has ne Pre-Outs and I woulnd't be able to connect the monitor-speakers.
Up to now there's plenty of space left in my M³ case, so I thought of fitting a High-Low-converter in it.
I don't know if the english term is the same ... It's a device that converts "speaker signal"
down to something you can send through a RCA cable (e.g. to active speakers.)

Those devices are mainly used in Car-Hifi when the car-radio has no pre out.
No idea if something like this exists for home-use.

It's just an Idea ... I just don't like the Idea of selling my nice 674 only because of the missing pre-outs.
At the time I bought it I had never even thought about active speakers.
The problem is that I'm a student and don't have enough room to place big floorstanding speakers.

I see this project mutating into some kind of all-purpose-weapon

 

[jinp6301]

ckkIII?

it sounds pretty neutral to me!