Covington Fireplace Ultra Treble Booster Trace

[maynut]

Just to chip in a little bit of extra info that might be of interest to those here - I found a photo online of the inside of a Cornish TB-83 and although the circuit is of course hidden, there is one component on display which appears to be a rectifier diode.
I'm sure this makes no difference to the sound and is probably just to prevent a reverse voltage from a wrongly corrected battery, but for those of us who want exact details, hopefully this is of interest.
Here's the pic:
https://www.google.co.uk/search?q=inside+a+cornish+TB83&espv=2&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiplZnCiqHTAhUIIMAKHbxjAYYQ_AUIBigB&biw=1280&bih=906#imgrc=q27oWUGxxenGbM:
or here:
https://reverb-res.cloudinary.com/image/upload/s--n_bh0Lo5--/a_exif,c_limit,e_unsharp_mask:80,f_auto,fl_progressive,g_south,h_620,q_90,w_620/v1470947841/wtbbn4nzwild5wouzxjp.jpg

Also I managed to reach Greg Covington online and although he was of course reluctant to give away the schematic, he did say that his 'Ultra' booster was an attempt to get his boxes closer to being identical to the TB-83 - before he eventually gave up and took the Cornish apart to discover he was only one component's difference to it.
No mention of what that component was exactly but I'd bet Nick's efforts here are as close as you will find to a real TB-83.

Cheers guys

[nickbungus]

Nice work.   Surprised he didn't give you the schematic.   He doesn't sell anymore and he was once in the same boat as us.   I've never been sure about the ethics of tracing but he's done it so i can't understand why he hasn't helped.

[maynut]

Yes, kind of my thoughts too - however, although he doesn't strictly build any more, he is still offering to build one-offs for those that contact him as he did with me.
Seems he'd rather still 'keep his hand in' as it were, so I guess I can understand why he wouldn't share his schematic 

Perhaps it's because he'd spent so much time and effort building/modifying them 'blind' and got so close on his own without tracing, just listening and tweaking. Who knows.

Maybe I'll have another bash ha ha

[alfafalfa]

If you want the schematic, just google it, you can find the schem as well as the board !

[nickbungus]

I've never seen the Cornish schematic.   The Fryer one is easy to find.   .  Pease share a link Alfafalfa

[maynut]

Hi Alfafalfa,

Glad you have found the Cornish schematic, even better the board, a lot of us on here have been searching for it for ages. Please do share the link so others can benefit.
Thanks

[nickbungus]

[maynut]

Man, has nobody opened up a Cornish yet?  Seems like by now someone other than Greg Covington would have done it!...