Solid State Guitar Amp Forum | DIY Guitar Amplifiers

Solid State Amplifiers => Schematics and Layouts => Topic started by: phatt on March 11, 2013, 09:50:58 AM

Title: Kustom 100 head
Post by: phatt on March 11, 2013, 09:50:58 AM
Thumbs up for this one,,I've been playing at the local pub (Sunday arvo jam) and I noted a chap used this Amp through a PA which at first sounded horrible but I was impressed that he quickly dialed in a sound that was Very much the classic thick marshall sound.
He was playing a stock Mex strat,, no pedals.

So I looked it up and first hit was this;
http://guitar-dreamer.blogspot.com.au/2012/04/kustom-quad-100-dfx-mod.html

Wow how lucky you can be sometimes.
Note the link to a PDF of the Schemo as well. :dbtu:

I'm not much interested in the digi efx trip, it's more the analog preamp section that impressed me. This is likely considered a cheap Amp but boy oh boy it nails that classic sound very well.

My guess (after some quick and dirty simulations) I Note the input is much like a lot of fender SS inputs which kills everything below ~100hZ. Then C13 and C15 roll off a big slope above 3khZ forming a close to perfect Marshall response curve.

IC8B is obviously some kind of cab sim (which I've not yet simulated). This drives IC8A , a balanced line out. Which is the output that drove the PA and the sound I heard.
I've not had time to play through the rig myself but my ears are experienced enough to recognize that classic sound. 8)
May not be a heavy metal machine but a few pedals might evoke some other tones.

Having spent many hours trying all sorts of cab sim type circuits which are often complicated,, this might be a much simpler build as I would not need all the fancy switching for crunch, clean, drive, boost and efx.

Hum, I might have to get out the bread board and do some testing.
Damn so many ideas I get but I run out of time to test them all.  >:(

Interested in hearing others who have heard/used this Amplifier?
Ed; Oh forgot to ask;
Any of you talented folks wish to make observations pro or cons,, I'm all ears.
Phil.
Title: Re: Kustom 100 head
Post by: newbiediy on March 11, 2013, 11:05:30 AM
I'm very interested, Phill. I followed your link but was unable to find the pdf link. A direct link would be appreciated.
Thanks before.
Title: Re: Kustom 100 head
Post by: Roly on March 11, 2013, 11:33:03 AM
Kustom
Used by Creedence Clearwater Revival.
Padded covering
Two front ports
Came in 'orrible colours
1971

(http://upload.wikimedia.org/wikipedia/commons/thumb/3/32/Kustom_200_bass_amplifier_%281971%29.jpg/220px-Kustom_200_bass_amplifier_%281971%29.jpg)
Title: Re: Kustom 100 head
Post by: phatt on March 12, 2013, 01:26:10 AM
Hi Roly,, ? link seems to work ok for me.
Not to worry Schemo here;
https://rapidshare.com/files/2168011693/quad_100dfx_kustom_guitar_amp_sm.pdf

The Amp head in question, see pic.

The chassis could easy fit into a much smaller box.
Obviously trying to make it look big for the Valvey look fashion statement,, Like wot 4???
Uses a STK404-100 chip as poweramp.

Yep I do recall seeing a few of those bright pin cushioned heads around in my youth. lol.
Phil.