HiFi Premp schematics?

[Mlaen]

I'm searching for a hifi preamp schematics for my 2*25W amp.
I have been searching trough google for two days and found nothing. The problem is that I would wanted to have a transistor preamp (jfet, mosfet) with tone controles.
I found only http://www.albertkreuzer.com/ but that is for guitars
Can anyone help me with that please?

 

[wim]

You can look at the website of Rod Elliot, project 37 (discrete pre).

There are onters on that site, but not discrete.

 

[Mlaen]

Yes I saw that but it doesn't have a tone controls (bass, treble)
Something else?

 

[wim]

It is easy to implement a tonecontroll section of another pre-amp design from Rod Elliot. Look at project 02 or 97.

 

[Mlaen]

How about like this:

Ok, for start I found this tone conctrole circut: http://www.mitedu.freeserve.co.uk/Circuits/Audio/t-ctrl.htm

The schematics of my amp is in attachment. This amp has no need for preamp...
So my question: how do I connect all this:
Should I inlude the preamp or not?
If yes; do I connect tone control circut before or after the preamp?
I'm little confuzed about this so please help mi with this one?
Thanx!

 

[Mlaen]

Hmmm, just saw that there is no attachment... here's the link to amp: http://www.electronics-lab.com/projects/audio/001/index.html

 

[renjiish]

try this jlh preamp.it is very good

http://www.tcaas.btinternet.co.uk/jlhmodpre.htm

 

[bigpanda]

Hi,

So you've finished your 25W x 2? How do you find it?

 

[Mlaen]

@renjiish
- Looks big I'll see. Thanx for that!

@bigpanda
- I can't tell you how it sounds. It's not 100% complete + still waiting for transformer to arrive.
Did you get my email?

 

[bigpanda]

Heatsink

Hi Mlaen,

Don't know you send me a mail until I read your post. I had use two heatsink : one was 12"x4.5"x1.25" and the other was 3"x3"x6". The first one is what I have purchased from a electronic store while the second one is a design from a particular company for their amplifier kits but I happen to be able to get a piece from them. Either one works fine. Sorry I don't have a DC to shoot them and post the pictures. But the pcb I mailed you was a bit different from the one I built. The one I had have 2 seperate small heatsink for the drivers(per channel) and a big heatsind for the outputs. The one I had for you had only 1 heatsink for both the drivers and the outputs but I think the 1st heatsink should be able to handle them all. But you would have to use a L shaped bracket for that.