Carlsbro Sidewinder Circuit - UK Vintage Radio Repair and Restoration Discussion Forum

Geoffbarber · 31st Aug 2014, 10:24 am

Hi Folks,

Does anyone have a circuit diagram for a Carlsbro Sidewinder 60w guitar amplifier, please.
I've tried Carlsbro, but no joy !
Regards
Geoff

Diabolical Artificer · 31st Aug 2014, 10:48 am

John Chambers site chambonino.com has a lot of Carlsbro related articles and schematics. See www.chambonino.com/carlsbro/carlwires.html

Sorry didn't have time to look if the 60w Sidewinder was amongst them, but if not , maybe you can get an idea of how Carlsbro configered their amps.

Good luck,Andy.

Geoffbarber · 8th Sep 2014, 1:04 pm

Hi Andy,
Many thanks for your prompt response.
I'm still waiting a reply from John as there's no circuit on his website. I did get routed to an old Ebay advert as the seller did say he was selling a CCT with his Sidewinder, however he deleted the CCT because he has so many calls for a copy. This does show there's a real requirement out there for a CCT.

However back to the real reason a need a CCT: Although me Sidewinder is working fine I need to find out why the amps bass resonance is so poor. For example, the output is 15dB down at 500Hz and a whopping 23dB down at 100Hz. Its no wonder a lot of people say the amp hasn't the warmth of a valve amp.

In the absence of a CCT I guess I'll have to do it the hard way!

Any help would be appreciated
Regards
Geoff

jamesperrett · 8th Sep 2014, 1:45 pm

The first things I would look at would be the coupling capacitors. I would also look at the tone controls - is there a way of bypassing them to check?

Diabolical Artificer · 9th Sep 2014, 1:23 pm

As I said I couldn't see the Sindwinder circuit , but thought you may be able to glean some info from the circuits of other models of the same wattage etc. Really it shouldn't be too tricky to back engineer and draw your own.

It also may be worth while contacting Carlsbro themselves, I think they still make amps.

If you want to contact John, its best to ring him after 12pm. He doesn't really do emails.

Good advice above, you could also try changing the caps on the tone circuit or put bigger value caps on the cathode bypass caps on the pre amp stage. They're usually 25u, you could try anything up to 100u, but start low like a 33/47u.

Andy.

Geoffbarber · 9th Sep 2014, 6:08 pm

Hi Andy,
Many thanks for the advice. I had tried Carlsbro but as a new company has taken over carlsbro support they don't have any circuits for older amps.
Spent today tracing out the tone circuit and found the 4.7nf from the MID pot has gone low. Replaced and the output is now only 4dB down at 100Hz and it sounds a lot warmer.

Thanks again for your time.
Geoff.

31st Aug 2014, 10:24 am	#1
Geoffbarber Triode Join Date: Apr 2013 Location: Scarborough, North Yorkshire, UK. Posts: 22	Carlsbro Sidewinder Circuit Hi Folks, Does anyone have a circuit diagram for a Carlsbro Sidewinder 60w guitar amplifier, please. I've tried Carlsbro, but no joy ! Regards Geoff

31st Aug 2014, 10:48 am	#2
Diabolical Artificer Dekatron Join Date: Jul 2009 Location: Sleaford, Lincs. UK. Posts: 7,669	Re: Carlsbro Sidewinder Circuit John Chambers site chambonino.com has a lot of Carlsbro related articles and schematics. See www.chambonino.com/carlsbro/carlwires.html Sorry didn't have time to look if the 60w Sidewinder was amongst them, but if not , maybe you can get an idea of how Carlsbro configered their amps. Good luck,Andy. __________________ Curiosity hasn't killed this cat...so far.

8th Sep 2014, 1:04 pm	#3
Geoffbarber Triode Join Date: Apr 2013 Location: Scarborough, North Yorkshire, UK. Posts: 22	Re: Carlsbro Sidewinder Circuit Hi Andy, Many thanks for your prompt response. I'm still waiting a reply from John as there's no circuit on his website. I did get routed to an old Ebay advert as the seller did say he was selling a CCT with his Sidewinder, however he deleted the CCT because he has so many calls for a copy. This does show there's a real requirement out there for a CCT. However back to the real reason a need a CCT: Although me Sidewinder is working fine I need to find out why the amps bass resonance is so poor. For example, the output is 15dB down at 500Hz and a whopping 23dB down at 100Hz. Its no wonder a lot of people say the amp hasn't the warmth of a valve amp. In the absence of a CCT I guess I'll have to do it the hard way! Any help would be appreciated Regards Geoff

8th Sep 2014, 1:45 pm	#4
jamesperrett Octode Join Date: May 2007 Location: Liss, Hampshire, UK. Posts: 1,876	Re: Carlsbro Sidewinder Circuit The first things I would look at would be the coupling capacitors. I would also look at the tone controls - is there a way of bypassing them to check?

9th Sep 2014, 1:23 pm	#5
Diabolical Artificer Dekatron Join Date: Jul 2009 Location: Sleaford, Lincs. UK. Posts: 7,669	Re: Carlsbro Sidewinder Circuit As I said I couldn't see the Sindwinder circuit , but thought you may be able to glean some info from the circuits of other models of the same wattage etc. Really it shouldn't be too tricky to back engineer and draw your own. It also may be worth while contacting Carlsbro themselves, I think they still make amps. If you want to contact John, its best to ring him after 12pm. He doesn't really do emails. Good advice above, you could also try changing the caps on the tone circuit or put bigger value caps on the cathode bypass caps on the pre amp stage. They're usually 25u, you could try anything up to 100u, but start low like a 33/47u. Andy. __________________ Curiosity hasn't killed this cat...so far.

9th Sep 2014, 6:08 pm	#6
Geoffbarber Triode Join Date: Apr 2013 Location: Scarborough, North Yorkshire, UK. Posts: 22	Re: Carlsbro Sidewinder Circuit Hi Andy, Many thanks for the advice. I had tried Carlsbro but as a new company has taken over carlsbro support they don't have any circuits for older amps. Spent today tracing out the tone circuit and found the 4.7nf from the MID pot has gone low. Replaced and the output is now only 4dB down at 100Hz and it sounds a lot warmer. Thanks again for your time. Geoff.