Fuchs ODS too spiky on the treble side

[phsyconoodler]

I've got a Fuchs 100 watt ODS and it is way too trebly even with the treble control all the way down with single coil low-output guitars.
I notice that most of my builds are somehwhat the same with stock values.
Has anyone tried using a more Fendery value coupling cap/bypass cap arrangement for getting the goods with low output single coils?
I bet it will sound great.
I'm going to start re-voicing the Fuchs and I will update my results in a couple of days.
I can't stand the treble bite of these amps!

[alvarezh]

Hi, Andy (Fuchs) is a forum member, I would think he's the most appropriate person to take advise from on this issue. Why not P.M. him?

I don't remember his username, perhaps someone else can come up with it.

All the best.

[stelligan]

FUCHSAUDIO

Strats and these amp types have always been an adventure for me. Good luck with the re-voicing. I'll bet Andy has some tricks up his sleeve......

[phsyconoodler]

Seems pretty basic to me.Bigger bypass caps and larger coupling cap values.
The amp is even a bit too bright with some humbuckers.

It has 1uf on the first preamp cathode and the rest for v1 and v2 are 4.7uf,pretty standard Dumble except for the 1uf.
Way to small for strats IMHO.
How much damn treble do you need?

[ATL Strat]

Dumble 123 is supposed to be a strat-voiced dumble. The attached schematic was posted a while back, but I forget who posted it (maybe 10thTX?). Maybe this will help you out.

[phsyconoodler]

I pulled the board and replaced a few bypass caps.He has a switch that switches a couple of caps out in the preamp section and it really made zero difference which way it was so I just went ahead and popped out the 4.7uf and 1 uf caps and replaced them with 22uf caps.
Not only does the clean sound infinitely better with my strat with Texas Specials,the overdrive sounds way better too.
I tried a couple of speaker cabinets,one with a pair of greenbacks that was not really doing it and a peavey cab loaded with a pair of freshly reconed Black Widows.
Wow! That cabinet sounds incredible!
All you have to do to make it humbucker friendly is turn the treble and bass controls to your liking.
Overall,it sounds WAAAYYYYY better and the spiky treble is gone for good.
Nasty amp to work on by the way.I'm not liking the PC board at all.The amp sounds good now and that's all that matters.

[Structo]

Does the Fuchs have a bright cap on the volume pot?

[phsyconoodler]

No it has a bright switch.
I also tried it through a Boogie with a Black shadow.Stellar!

It just doesn't sound good passing all that treble early on.
I just built a 22 watt Dumble style amp with a pair of 6V6's and I used 10uf caps and it's really much better sounding than the Fuchs.I use Hammond Iron.Pretty much superior in every aspect.
I may even swap the 10uf's for 22uf's in that one too.The guy I built it for only uses single coils.

At least this Fuchs is useable to the customer now.As it was it was an icepicky monster.We even tried it through a Fuchs cab loaded with Red White n Blues and a pair of EVM 12L's.Both were icepick city.
With the bypass cap change it is really nice.

I have had Fendery/Dumbly builds that needed to have the bypass caps lowered to as low as .68uf but this Fuchs was nasty.Not no more!

[ATL Strat]

You should try some G1265 speakers sometime if you have access to any. They do wonders to tame "ice-pickiness" and they sound really nice in Dumble-style amps

[aflynt]

My #102 build sounds great with my Strat in its stock form as long as I use the D'Lator. Without the D'Lator, removing the master bright cap and putting a 330pF/250K/330pF network on the send/return makes it sound much better.

-Aaron

[phsyconoodler]

I've got a G1265 coming for my customer.He agrees that we should be using that speaker.

We did get it in the zone but the bypass caps I changed should have made much more of a difference than they did.
The reverb circuit may be adding treble too.
Fuchs may be brilliant,but I can't stand that amp.Simple is always better in my book.
The tone controls are wired wierd too.Usually you can jumper the terminals on the bass pot to get it to work a different way,but jumpering this control did nothing at all,so I removed it.
I don't like it.Simple as that.

[Structo]

What size couplers does it have on the output of the phase inverter?

I noticed that had a pretty big frequency change on my amp which was too bassy, so I reduced them from .1uF to .05uF.

So if yours are lower than .1uF it might be a place to visit.

[vibratoking]

This won't solve your problem, but maybe offer a different impression of Fuchs' amps. I have ODS50 combo. It is not a bright amp. In fact, it is very smooth. Almost too smooth. There are times that I wish it was brighter. I put a Scholz Sugarcone in it to get more highs. Yours sounds very different I suppose.

[Chris333]

I kinda wondered if something may be wrong with the OP's amp. I've only played one Fuchs, but my ODS 30 is at the other end of the scale from ice-picky.

[mlp-mx6]

Agreed. I'd check the ground connection(s) for the tone stack as a start.