Search found 5695 matches

by simon
Mon May 13, 2024 9:49 pm
Forum: Speakers
Topic: TG "The Loudspeaker" Build (Sort of)
Replies: 168
Views: 16749

Re: TG "The Loudspeaker" Build (Sort of)

Yes very interesting. I can't help thinking that getting an adequately balanced platter, with suitable thickness, roundness and centrality would be exceptionally difficult for DIYers though.
by simon
Fri May 10, 2024 1:51 pm
Forum: Valves
Topic: Valve amplifier service
Replies: 200
Views: 98753

Re: Valve amplifier service

I had a bit more success this morning and ended up paralleling 4k7 giving 3k8 overall. Interestingly I think some of the instability I had yesterday was due to the USB C plug in DAC converter thingy I use with my phone for testing - it was the Fostex 208eZ cones moving worryingly way more than I've ...
by simon
Thu May 09, 2024 10:13 pm
Forum: Valves
Topic: Valve amplifier service
Replies: 200
Views: 98753

Re: Valve amplifier service

I very briefly clipleaded 2k2 resistors parallel to the 20k earlier. There was a bit of a squeak as it powered up, then it stopped. Turn the volume pot and it squeaked again. Stop turning the volume pot and the squeak stopped. When I say squeak it was reasonably high frequency which changed before s...
by simon
Tue May 07, 2024 10:52 pm
Forum: Valves
Topic: Valve amplifier service
Replies: 200
Views: 98753

Re: Valve amplifier service

Yes. This amp's been a bit, um, temperamental, so there's every chance it won't be happy. Only one way to find out.
by simon
Mon May 06, 2024 9:13 pm
Forum: Valves
Topic: Valve amplifier service
Replies: 200
Views: 98753

Re: Valve amplifier service

I think I get it now thanks. Worth a try to see what happens I suppose. Easier than redoing the first stage.
by simon
Mon May 06, 2024 8:54 pm
Forum: Valves
Topic: Valve amplifier service
Replies: 200
Views: 98753

Re: Valve amplifier service

Nick wrote: Mon May 06, 2024 8:35 pm However its also possible increasing the NFB will make the amp less stable.
But as I'd be decreasing the ratio it should be okay then?
by simon
Mon May 06, 2024 8:11 pm
Forum: Valves
Topic: Valve amplifier service
Replies: 200
Views: 98753

Re: Valve amplifier service

Okay, I'm in unknown waters :-). The NFB increases the gain, yes? I like the idea of paralleling R18, thanks!
by simon
Mon May 06, 2024 12:32 pm
Forum: Valves
Topic: Valve amplifier service
Replies: 200
Views: 98753

Re: Valve amplifier service

A reminder of the circuit: . WAD K5881 mk 2 small 2.png . Consulting the bible (thank you Mr Jones) the gain of the SRPP is around 82. So I'm guessing really that a gain more like 30 might be better. Playing with different op points for the existing ECC83 pre valve as a simple common cathode stage, ...
by simon
Mon May 06, 2024 12:07 pm
Forum: Valves
Topic: Valve amplifier service
Replies: 200
Views: 98753

Re: Valve amplifier service

The amp has been pretty well behaved at Dave's for three months now. It's still had its odd moment and Dave's had to use ground breakers at times, which isn't great as he can hear the device. But mostly it's been okay. Phew. Dave wanted to try a volume pot in the amp itself rather than use a pre amp...
by simon
Sat May 04, 2024 8:13 pm
Forum: Everyones Projects
Topic: C3g Aikido Phono
Replies: 327
Views: 101479

Re: C3g Aikido Phono

Slow progress but the Boozehound Labs stage is complete. It works, as in put the needle on the record and music comes out of the speakers. I didn't have chance to listen earlier, only check that it actually works. Sounded okay as far as I could tell and I think has more gain than the step ups. . 202...
by simon
Fri May 03, 2024 9:28 am
Forum: Speakers
Topic: TG "The Loudspeaker" Build (Sort of)
Replies: 168
Views: 16749

Re: TG "The Loudspeaker" Build (Sort of)

That's frustrating about the panel sizes, what do you put it down to? At first I wondered if it might be thickness of glue, but it wouldn't account for 1.8mm. I find I tend to oversize some panels by a couple of mm when I'm cutting out so I can trim rout flush at the end. A reflection of my woodwork...
by simon
Wed May 01, 2024 1:14 pm
Forum: New Users
Topic: Hi from Germany!
Replies: 23
Views: 1688

Re: Hi from Germany!

I have nothing to add to this thread, apart from hello!, but it's fascinating. Please keep up the discussion.
by simon
Tue Apr 30, 2024 12:34 pm
Forum: Speakers
Topic: TG "The Loudspeaker" Build (Sort of)
Replies: 168
Views: 16749

Re: TG "The Loudspeaker" Build (Sort of)

Yes I know what you mean. I've used four coats of water based varnish, lightly rubbed down with brown paper between coats, on small bits of oak, then a wax polish. And it does somehow look a bit unnatural. I wonder if it needs a light stain first to enhance the richness of oak?
by simon
Sat Apr 27, 2024 9:46 pm
Forum: Everyones Projects
Topic: More NVA Board Based Stuff
Replies: 17
Views: 1418

Re: More NVA Board Based Stuff

I can also offer freebies! I use a DCB1 buffer with a PCB I drafted and I have spare boards. It needs LSK170s but Nick kindly sent me a few to match for a project and I'm sure he wouldn't mind me passing on the 4 needed. It's got a mute delay but needs a bipolar PS. I've probably got some SuperReg b...
by simon
Fri Apr 26, 2024 9:52 pm
Forum: Assorted Stuff
Topic: RCA Phono Plug Recommendations
Replies: 9
Views: 539

Re: RCA Phono Plug Recommendations

My favourite price! Cheers, I'll drop you a text.