Search found 5381 matches

by ed
Fri Apr 21, 2023 2:39 pm
Forum: Solid State
Topic: even more lateral fets
Replies: 83
Views: 56488

Re: even more lateral fets

moving on....
mofo2 panels1.jpg
mofo2 panels1.jpg (154.8 KiB) Viewed 5516 times
mofo2 ps1.jpg
mofo2 ps1.jpg (197.34 KiB) Viewed 5516 times
mofo2 pcb1.jpg
mofo2 pcb1.jpg (112.91 KiB) Viewed 5516 times
by ed
Thu Apr 20, 2023 12:32 pm
Forum: Beginners
Topic: Valve Headphone Amp
Replies: 40
Views: 21730

Re: Valve Headphone Amp

by ed
Thu Apr 20, 2023 11:20 am
Forum: Beginners
Topic: Valve Headphone Amp
Replies: 40
Views: 21730

Re: Valve Headphone Amp

Hi Simon If it's of any use, here is the original circuit in rough. I mention it because It shows the relay that allows the hpa to sit between the dac and the power amp. With the hpa switched off the signal is routed directly from the dac to the power amp. when the hpa is switched on the relay route...
by ed
Wed Apr 19, 2023 4:57 pm
Forum: Beginners
Topic: power supply - senior moment
Replies: 2
Views: 3738

Re: power supply - senior moment

thankyou...12.2 and -11.9
by ed
Wed Apr 19, 2023 4:12 pm
Forum: Beginners
Topic: power supply - senior moment
Replies: 2
Views: 3738

power supply - senior moment

I've built a number of power supplies like the one shown, at least I think I have. This one doesn't work. The rail voltages are as shown on the diagram. The Tx is 2 x15v. it's supposed to supply + and - 12v but the negative rail comes out at -20v ish. At first I thought I'd got a dodgy 7912 so I bou...
by ed
Tue Apr 18, 2023 8:55 am
Forum: Beginners
Topic: Valve Headphone Amp
Replies: 40
Views: 21730

Re: Valve Headphone Amp

Hi Simon I’m a bit slow, I didn’t realise the questions might still be outstanding. C2 and C3 are the blocking caps because it’s single ended and there is a voltage on the FET source. R8 is the output load and in the spice diagram it represents the headphones. As Nick has pointed out, it is a buffer...
by ed
Mon Apr 17, 2023 7:23 pm
Forum: Beginners
Topic: Valve Headphone Amp
Replies: 40
Views: 21730

Re: Valve Headphone Amp

Why use ECX10N20? Because it "sounds good"? Is suited to the task? It looks like it's "audio grade" but now obsolete - is it likely to be superior to say IRF510? not obsolete.... https://www.profusionplc.com/parts/ecx10n20 yes, very much superior to irf510 IMO current builds I'm...
by ed
Mon Apr 17, 2023 7:20 pm
Forum: Beginners
Topic: Valve Headphone Amp
Replies: 40
Views: 21730

Re: Valve Headphone Amp

Why use ECX10N20? Because it "sounds good"? Is suited to the task? It looks like it's "audio grade" but now obsolete - is it likely to be superior to say IRF510? not obsolete.... https://www.profusionplc.com/parts/ecx10n20 yes, very much superior to irf510 IMO current builds I'm...
by ed
Sun Apr 16, 2023 1:33 pm
Forum: Beginners
Topic: Valve Headphone Amp
Replies: 40
Views: 21730

Re: Valve Headphone Amp

A couple of things came to mind after your last post. Do you want a headphone amp or do you want to experiment more with valves or do you insist on designing/ building a headphone amplifier. There doesn’t have to be, but there is a distinction. Your post reminded me of the simple latfet hpa that I p...
by ed
Sun Apr 09, 2023 7:12 pm
Forum: Assorted Stuff
Topic: what are you doing ?
Replies: 1308
Views: 436890

Re: what are you doing ?

I was going to do ours last summer but the price of the teak slats put me off...cheapskate as usual...
Sandrine was sitting on it this afternoon but suggested that I didn't risk it...the cheek of it.
bench.jpg
bench.jpg (177.35 KiB) Viewed 6581 times
by ed
Sun Apr 09, 2023 1:53 pm
Forum: Assorted Stuff
Topic: web domain names
Replies: 1
Views: 2879

web domain names

I have had a web domain registered with freeparking for nearly 25 years. In fact I have 2 domains with them at the moment. In late 2022 freeparking changed it’s name to namesco.co. Every year my 12 monthly renewal has increased but this year seemed a bit excessive. I have just renewed Sandrine’s dom...
by ed
Sun Apr 09, 2023 11:50 am
Forum: Your Fave Artists
Topic: What Are You Listening To Right This Minute?
Replies: 6152
Views: 1875348

Re: What Are You Listening To Right This Minute?

been taking a trip down memory lane...back in 1973 everybody thought I'd lost it when I kept raving about these guys...not sure if most of the members are the same but for sure David Surkamp is...

I had no idea they were still around

by ed
Thu Apr 06, 2023 10:41 pm
Forum: Solid State
Topic: even more lateral fets
Replies: 83
Views: 56488

Re: even more lateral fets

a bit more.... I don't like tapping blind holes, I have tried and failed in the past...so my M.O over the last 20 years has been to drill through heatsinks between the fins and attach circuit boards to the sinks with nuts and bolts and spacers. this build was slightly different because I had the pcb...
by ed
Thu Apr 06, 2023 10:16 pm
Forum: Assorted Stuff
Topic: Nothing In Particular
Replies: 16439
Views: 4652625

Re: Nothing In Particular

No burning/melting? that was what surpriised me the most. it cuts about the same pressure as 6mm ply and leaves a bit of feather edge which is easy to rub off with a file or emery block. I was fully expecting it to clog the band and get sticky, but not a bit of it......perfectly clean cut. I've ela...