bremen

Tried Switchelectronics?

I guess I need to be finishing that power supply! Sorry, been very distracted (and now I'm Tom Dick 🤢)

There are so many pages of this and so many repetitions, so apologies if I'm not the first with The w**ker Brothers Edit: can I give the Nanny Filter a Hard Stare? I only changed one letter

The load on the secondary is reflected back to the valves, though?

Understood. Thanks for confirmation.

Deep joy: I've fixed it, owner is delighted and I have a schematic to steal ideas from:-) 10⁶ thanks, @Dood

I have the same amp with a missing valve. I've been thinking of pulling its complement and running it into 8 ohms...sensible?

Anyone any recent experience of playing in US or EU without a visa? The UK subs got deported last month. I'm told that they'd regularly gigged there under the radar; I wonder if their luck just ran out or was it because of remarks they made about the Supreme Leader. We have offers but the cost of visas rules out doing it legitimately And EU. How relaxed are they? Again, we have offers...at least visas are easier but I believe they're done country by country. No such thing as a EU visa. Brexit has been the most depressing series of events in my life (and that of my sister, EU resident for 15 years)

I love the "free B+". I did that for my Fenderpeg-Elliott. A dry joint or dried up cap in there would be another candidate for the cause of the BZZZZZZZ

Thanks, el Dooderino! I played in a band with a guitarist used a Valve State, I did enjoy its crunchy goodness.

Gday I'm about to have this combo delivered for me to repair. Fault is an intermittent very loud 100Hz buzz. Most likely a dry joint on a reservoir cap. But just in case it's not that simple, anyone got a schematic? Cheers

Another effective variation of that is a pcb drill bit. Heat the pad, push the drill through the hole while the solders melted, then spin the drill bereeen fingers as you remove the iron to prevent the solder sticking.

Yup, C1-6 begin to roll off the tone at about 16MHz 😉 C17 will isolate the input stage from the +v rail and any nasties thereon, eg 100Hz ripple or any DC variation as big currents into speaker drag it down.

Really? Those drivers must be something special, it's hard to model anything that small (per driver) with that response in winisd. Not doubting you, I know you worked with Ampeg.

Fwiw, here's the Ashdown variant. The output devices are plastic package equivalents of the originals. All now obsolete but equivalents available from Profusion PLC. Additions: C1, 2, 3, 4, 5, 6 (for hf stability?) and C17 (lf stability? Power supply noise rejection?) Ashdown ABM Schematics.pdf

2dB more

Hard Stare...or a commendation for lawyerly rule bending?

How the choice of a tant indirectly brought down a company. Probably.

Traditionally, tants were used for coupling as they could take small reverse polarity volts better than the electros of the day. Nowadays they're used where electros cant do small enough size/low enough esr/high enough capacitance all at once. Theyre a last resort at the last place i worked. They do flame quite amusingly when they lose their tempers though.

Even when they do spec the fr, I don't believe it https://www.musicstore.com/en_GB/GBP/Ampeg-SVT-810-E-Box-800W-4-Ohm-8x10-Speaker/art-BAS0000443-000

Iron Malden. The Essex tribute band twinned with Yorkshire's Highway to Hull

Is that the input coupler? I wonder why replacing a horrid tant with a nice shiny electro would cause instability. Genuine question. I use film caps for input coupling and mlcc and electros elsewhere on my clones and they're plenty stable.

They're amazingly robust, simple designs. I shorted the output to the negative rail by careless placement of a Croc clip, which arced bright white, gave off a lot of smoke and welded shut. Power off, chiseled it off and it was fine.

If it's the Clive Button mosfet board (based on a Hitachi applications note) it looks like it hardly changed as the product line evolved, and now Ashdown are using it. Any of these any good? There's more somewhere that show the resistor feeding the long tail pair split with a decoupler to ground, and some with gate capacitors added to the output devices trace-elliot_GP11-AH350-AH500-MK-V-BASS-1.pdf trace-elliot-GP7-300w-7-band-1.pdf

https://sleafordmods.bandcamp.com/album/mork-n-mindy