Treble pot and Preamp boost questions

Overdrive Special, Steel String Singer, Dumbleland, Odyssey, Winterland, etc. -
Members Only

Moderators: pompeiisneaks, Colossal

Post Reply
User avatar
dobbhill
Posts: 434
Joined: Sat Jan 22, 2005 12:04 am
Location: Louisiana

Treble pot and Preamp boost questions

Post by dobbhill »

I have a 250k audio treble pot in mine. That's what I had around, and it works. Does anyone know if it will make a big difference if I change it to a linear pot??

I don't have the Jazz/Rock switch installed. When disconnecting the bottom of the treble pot from the top of the bass pot for the preamp boost, is the bass cap supposed to be connected to the bottom of the treble pot or the top of the bass pot? I tried it both ways and found that the boost was way too big with it connected to the bass pot, and very subtle when connected to the treble pot.

Thanks for your suggestions and experience. I have gained much from all of you and appreciate all your help. I hope I can be of service to some of you.

D
llemtt
Posts: 332
Joined: Sat Feb 04, 2006 3:13 pm

Re: Treble pot and Preamp boost questions

Post by llemtt »

250K lin for treble is better that audio taper, old fender amps used audio taper but it was a 30% taper, not the common 15% type

Teo
dogears
Posts: 1902
Joined: Wed Feb 01, 2006 1:29 pm

Re: Treble pot and Preamp boost questions

Post by dogears »

Hi Teo,

I am not sure I agree.... I have been favoring the audio taper trebles for a little while now. Fwiw, the K&M amps I have seen had audio taper treble as well. I like the look of the pot up at 2 oclock instead of down at 9 oclock... Just some Feng Shui!! LOL

I use the Skyliner tonestack. 250ka Treble, 250ka Mid, 500ka Bass, 150k slope, .001uf on bass pot, .01midcap

30% tapers would be sweet!!!! Too bad they are so rare.
llemtt wrote:250K lin for treble is better that audio taper, old fender amps used audio taper but it was a 30% taper, not the common 15% type

Teo
User avatar
Funkalicousgroove
Posts: 2235
Joined: Mon Jul 25, 2005 8:04 pm
Location: Denver, CO
Contact:

Re: Treble pot and Preamp boost questions

Post by Funkalicousgroove »

You can get 30% ers, they're just spendy!! Westlabs gets like $15ea!!
Owner/Solder Jockey Bludotone Amp Works
User avatar
glasman
Posts: 1446
Joined: Wed Jan 19, 2005 10:37 pm
Location: Afton, MN (St Croix River Valley)
Contact:

Re: Treble pot and Preamp boost questions

Post by glasman »

Funkalicousgroove wrote:You can get 30% ers, they're just spendy!! Westlabs gets like $15ea!!
And the PEC's are not much cheaper.
Located in the St Croix River Valley- Afton, MN
About 5 miles south of I-94
aka K0GWA, K0 Glas Werks Amplification

www.glaswerks.com
User avatar
Funkalicousgroove
Posts: 2235
Joined: Mon Jul 25, 2005 8:04 pm
Location: Denver, CO
Contact:

Re: Treble pot and Preamp boost questions

Post by Funkalicousgroove »

I think the Westlabs are clarostat. Anyone ever mess with Bourns Conductive plastic pots?
Owner/Solder Jockey Bludotone Amp Works
llemtt
Posts: 332
Joined: Sat Feb 04, 2006 3:13 pm

Re: Treble pot and Preamp boost questions

Post by llemtt »

dogears wrote: I like the look of the pot up at 2 oclock instead of down at 9 oclock... Just some Feng Shui!! LOL
Yes you are right, always keep only stairs that go up :wink:
dogears wrote: 30% tapers would be sweet!!!! Too bad they are so rare.
Fender uses some in their current production amps, but buying from them as replacement parts is expensive and also Clarostats, Weber,... are very expensive.

BTW I use almost exactly the same values, only 250K-L for treble and .022u mid cap.
User avatar
dobbhill
Posts: 434
Joined: Sat Jan 22, 2005 12:04 am
Location: Louisiana

Re: Treble pot and Preamp boost questions

Post by dobbhill »

Thanks for the suggestions. I made some changes last nite:


the Skyliner tonestack. 250ka Treble, 250ka Mid, 500ka Bass, 150k slope, .001uf on bass pot, .01midcap

connected the bass cap to the bottom of the treble pot and the boost relay between the treble pot and top of bass pot.

local feedback on-off-on switch: 44meg-off-22meg

power amp feedback to 4 ohm tap.

Now I have a new amp and it smokes!! I've been playing the amp for 5 years and only thought it sounded good. Funk had the same experience expressed in a previous post.

Thanks again for the guidance and suggestions to all, especially dogears.

D
Post Reply