audio-talk

It's been a while and apart from it being a bit noisy, I'm very pleased. However it's never been totally quiet and I'm not 100% sure about the SMPS filaments for the GM70s; that being a bit of a compromise. So first bought Hammond transformers for this based on Rod Coleman's design for his regs http...

I reckon if the currents are huge and changeable then yes, it might make a difference. Many 100s of watts into super inefficient speaks, I'd want the power supply wiring short especially from the bridge to the caps. There I'd want it real short coz large caps, quite huge current pulses = mucho inter...

Ah yes, I wasn't very clear. The input phonos have always been grounded. I've never had any luck grounding the input sockets. In certain wiring layouts, usually a busbar system, many folk do this with success. I've never built a bus bar grounding system as IMHO, there are better wiring layouts. My ...

This amp which you may have seen ended up similar https://www.diyaudio.com/community/thre ... ll.271081/

Unsurprisingly, it seems a great idea to me to drive the finals balanced from a Tx.

It's an interesting thread.

Cheers,
Stephen

Have you tried a low impedance device in the d3a cathode to get the gain higher? Diode, led, RC combo would all sound different.

Looks like a good first go.

I realise a mangled PCB wasn't the plan but a few links for the heaters to get the right valves in wouldn't be wrong now that you got it going.

Hopefully your hum is down to regs not going quite right.

Depends on the cartridge. It's not a totally universal solution and only for MCs. A bunch of commercial stages do this.

IIRC, Nick's circuit is able to cope with a spread in the curves within reason which I think he is suggesting in some of his posts. That might be fine for the d3a. I've accepted the current valve situation for my power amps. Many will use, say more exotic (now) unobtanium/expensice DHTs like 45/46 e...

Could try and find E810F but probably same issue.

D3a last for ages. In the end they are vfm.

It was called lossy parafeed not by Thorsten but by Voltsecond. I've used it to couple to TVC 1u film with 22u BG and 1k in parallel. I thought it easier to terminate the LCR with the characteristic Z than work out the accurate drive Z unless driven direct off a pentode or similar. But then I don't ...

The classic 600r lcr module can cause some issues which is why some of late have taken a different course of higher Z all the way to 10k. 1.5k or thereabouts is seen as a "better" bet to keep away the issues associated with much higher z. Some get rid of the requirement of a huge coupling ...

With that lcr, don't you either have to drive it with a 600R source or terminate it with 600R?

I might have missed something with the driver as I'm looking at it on a phone.

That makes sense. HiFiCollective have just replied and their meter is calibrated so a couple of 47nF from them might be the way forward. When they say calibrated, what exactly does that mean? Calibrated to what? What is the accuracy of their meter? What is the accuracy of the standard it's being ca...

The hifihaven cct started as an earlier version of mine. I've conversed a lot with Salectric over the last decade or more helping with his deviation. He's still going so his latest is different to the build threads but I think he may have done a build thread for his latest. Many use the d3a as a tri...