The Signal Transfer Company

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#107
Mooly said:
Last one for today 🙂

This was a business list I found for the Topland Park. No Signal Transfer Company or GJC company listed that I could just see 🙁

19 Companies in HX7 5RW, Topland Country Business Park, Cragg Vale, Hebden Bridge - Endole
Click to expand...


Then it seems fair to say that the two ventures are closed for business - a great pity I think, because Doug Self's designs are really worth having if one is looking for genuine, high end performance at decent prices, IMHO.


I have built two of his designs: the class G power amplifier and a modded version of his 'Precision Pre-amplifier' for a multi-amped project which serves me very well indeed - that is to say that the sound quality and system reliability is totally beyond reproach, and although I am not intending to build anything more at present, it would be nice to know that his products are still available.
 
#114
Just got this from Gareth :



Hello Gerry,

The people at Topland have got in touch with me saying that they have had comms from you trying to get hold of me.


Full contact details, business and personal, are:


Landline: +44-1422-885196
Cell: +44-7779-385207
Email: signaltransfer@freeuk.com
gconnor@freeuk.com
gareth@gjcdesigns.co.uk


Hopefully this will establish contact.

With thanks and best regards,

Gareth





Gareth Connor.

The Signal Transfer Company,
Unit 9a, Topland Country Business Park, Cragg Road,
Mytholmroyd, West Yorkshire, HX7 5RW, England.
signaltransfer@freeuk.com
gconnor@freeuk.com
Tel: 01422 885 196
 
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#116
Glad to know they're still in business, let's hope it all runs smoothly with STC from now on - and I hope those who had previously given up on them will read these later posts so that they can get in touch with Gareth/STC for their requirements too.
 
#117
self pre amp

Gerry, when you say you built a modded version of the Self precision pre-amp what mods were you were referring to? I ask as I'm in process of building one myself (well its a project ongoing for 3 yrs but I now have some time!). Mods I will incorporate are in D Self's book 'small signal audio design' 2nd edition page 428 where he revisits some of the design thinking.
 
#119
Hi etlasr, Doug designed three versions of that pre-amp, the first, utilising 5532 op-amps, appeared in Electronics World magazine - then in collaboration with Peter Baxandall he redesigned it to produce a top end, no compromise unit using expensive LM4562 op-amps. It was published in Elector Magazine. The final version was published (I think by Jan Didden in Linear Audio Magazine), and was a kind of compromise between the first two.
The problem for me was:
a) I was not prepared to pay for the high expense op-amps; and
b) the required pot values: in version 1 they were 10k (noisy), version 2: 1k (which would apparently warm up appreciably in use) and version 3: 5k. I had only 2k5 pots and wanted to use them rather than buy new ones - likewise the op-amps: I had a large collection of 5532's and wanted to use them up rather than buy new ones of any type.
So my solution - also from Doug Self's articles - was to 'quad path' - that is, to use 4 paralleled 5532 op-amps and correspondingly lower value resistors to keep noise contribution low and enabling the use of my lower value pots (which do not warm up in service).
Unfortunately I do not own a copy of Small Signal Audio Design (yet), so not aware of what further suggestions he has proposed there, but I do have copies of all three of the designs listed above and will email those to you if you are interested in them for info and full circuit design and diagrams.
 
#120
Gerry, yes would very much like to see the info. Have sent you my email address by private message. I can send you the info from Self's book if you like. It's nothing radical just tweaks but as I'm building from scratch its worth doing.
 
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