Hi all - here's possibly some overkill in details of the system/environment and the problem I've experienced.
I will be moving things around in the rack/environment tomorrow and do some more testing/listening.
One of the monoblock amps cut out on me a few times - the first time after about an hour of playing. It would come back after being switched off but only for a few minutes.
The amp doesn't feel hot anywhere on the case and the power light was lit quite happily - but no sound. I switched XLR cables around and speaker cables - but it seemed it was just this one amp that was silent.
There was no smoke/pop/flash or anything untoward - the amp just cut out.
I did have the amps sat on a wooden block quite close to each other - about an inch apart and like this the left hand one would cut out.
There was a gap of about 3 inches to either side of each amp – so basically, they were in an enclosure which is open to the front and back but surrounds the amps.
I have since moved them apart - the one that cut out is now on a granite tile about a foot in front of the other. When set up like this it's been playing quite happily for about 25 minutes with no problems. In fact, like this they’ve been quite happy for just over an hour.
All the equipment I use has been built by other people since I have no DIY equipment skills 😊
I am using a DCB1 pre-amp which uses a Hypnotize DC B1 Jfet buffer with a Valab 50K stepped attenuator which I use at around the one o’clock position.
The speakers are Wilmslow Audio Gemini with the following specifications (copied from their website): Treble: Morel CAT308 Bass-mid: Morel CAW538 (x2) Frequency response: 40Hz - 22000Hz Sensitivity (2.83v/1m): 91dB Amp requirement: 30-150w Impedance: 4 ohm These use an external cross-over – again built by someone else and unfortunately, I don’t know the specs of these.
The speaker cables are Bigbottle Audio Spotfire.
The interconnects from the preamp to the amps are RCA->XLR using Van Damme Pro Grade XKE Oxygen Free Copper Dual Screened silver plated cable with Neutrix connectors.
I’m using a Puritan Audio PSM156 mains purifier with a variety of mains cables.
The mains cable to the amp which experienced the problem consists of Oyaide EE/FS-2.6mm solid core cable terminated with Furutech FI-UK mains plug and a Furutech FI-11 gold plated IEC. I’ve since swapped this over with the other amp for an MCRU power cable (not sure what version).
The whole rack is about 2 and a half feet from a radiator.
So – 2 monoblocks, same connectors, same speaker cables and 2 different power cables. One has experienced cut outs – the other has been fine.
Kevin had been very helpful over the whole thing and I am more than keen to keep hold of these and find a solution.
Since the original problem occurred and moving them apart and switching the power cables around they’ve performed perfectly. Weird 😊
I've moved things so the monoblocks are seperated from each other and with good airflow.
Unfortunately the one monoblock (let's call it 'A') playing up yesterday is still having problems. It was running fine for an hour or so yesterday afternoon - no problems but this morning it's refusing to play.
Started playing a track and there was about a minute of music from both channels and then 'A' stopped playing - no music from one channel. It did try to chime in again a couple of times but then refused to play ball.
Wondering whether I have a duff power cable I swapped it out for a generic kettle lead - no joy. Switch on - a few seconds of music then nothing.
Replugged the amp in to another socket - same story.
Swapped the monoblocks from left to right - and 'A' still plays nothing.
So one monoblock works fine and one seems to be working intermittently in that you can switch it on and it's fine then after 10-15 seconds it stops.
And just as I'm typing this it's chimed back in - I'd left the music playing whilst typing and it came back on. And then it's stopped again - coincidentally just as some drumming kicked in (playing Ozric Tentacles - The Domes of G'Bal).