Ferguson 396G Record-Player 3 valve amp!? - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

Edward Huggins · 17th Oct 2017, 8:29 am

It's not so much about the need for a 2 valve pre-amp with a very high gain (which is laible to worsen the problem) it's about the impedence matching of a tablet/smartphone/MP3 to the input stage of the valve amplfier. You might be missing the point here, creating extra work for yourself and yet not solving the problem.

McMichael488 · 23rd Oct 2017, 11:54 pm

Thanks Edward. Apologies for the delay, only just noticed your reply as it had moved to page 2 & I hadn't noticed!
I guessed I would be missing many points as I'm out of my depth at present

So impedence input mismatch.. Can I fix that? Could I use an input transformer if such a thing exists perhaps?

There's plenty of people who have successfully connected a line-in to their devices & it would make this set get used & enjoyed much more than just as a record player only. So I'm keen to do whatever modifications are necessary.
As I mentioned previously this was going to be scrapped & I got it for a cheap valved stereo amp to work on & learn on & improve as best I can.
I've bought some books to ingest. They are mainly concerned with valve radio repair.
Is there a valve amplifier building / repairing book anyone might know of to recommend please, that I may cross referance information from?
Thanks

I'd happily put a switch in that selects normal (original) operating mode for Gram input & modified mode for mp3 (line in) if need be.

peter_sol · 29th Oct 2017, 9:45 am

The tone control would only have reduced the treble as it was turned and you don't need to do that using your phone so if you have enough volume you are OK
no worry about impedance matching. a low impedance (phone) is ok feeding a high impedance valve amp.

17th Oct 2017, 8:29 am	#21
Edward Huggins Dekatron Join Date: Sep 2015 Location: Southwold, Suffolk, UK. Posts: 8,327	Re: Ferguson 396G Record-Player 3 valve amp!? It's not so much about the need for a 2 valve pre-amp with a very high gain (which is laible to worsen the problem) it's about the impedence matching of a tablet/smartphone/MP3 to the input stage of the valve amplfier. You might be missing the point here, creating extra work for yourself and yet not solving the problem. __________________ Edward.

23rd Oct 2017, 11:54 pm	#22
McMichael488 Triode Join Date: Jun 2014 Location: North Yorkshire, UK Posts: 20	Re: Ferguson 396G Record-Player 3 valve amp!? Thanks Edward. Apologies for the delay, only just noticed your reply as it had moved to page 2 & I hadn't noticed! I guessed I would be missing many points as I'm out of my depth at present So impedence input mismatch.. Can I fix that? Could I use an input transformer if such a thing exists perhaps? There's plenty of people who have successfully connected a line-in to their devices & it would make this set get used & enjoyed much more than just as a record player only. So I'm keen to do whatever modifications are necessary. As I mentioned previously this was going to be scrapped & I got it for a cheap valved stereo amp to work on & learn on & improve as best I can. I've bought some books to ingest. They are mainly concerned with valve radio repair. Is there a valve amplifier building / repairing book anyone might know of to recommend please, that I may cross referance information from? Thanks I'd happily put a switch in that selects normal (original) operating mode for Gram input & modified mode for mp3 (line in) if need be.

29th Oct 2017, 9:45 am	#23
peter_sol Octode Join Date: Aug 2003 Location: Welwyn Garden City, Herts. UK. Posts: 1,906	Re: Ferguson 396G Record-Player 3 valve amp!? The tone control would only have reduced the treble as it was turned and you don't need to do that using your phone so if you have enough volume you are OK no worry about impedance matching. a low impedance (phone) is ok feeding a high impedance valve amp.