Finished building my first amp!

Misterg

thermionic said:

Pretty sure I read somewhere about leaving the mains lead plugged in but switched off to discharge filter caps, I should check the books I have...

That sounds like the standard advice to control/avoid static damage when working on computers....

ICBM

You need to be careful doing that - the switch on the wall socket will be for the live only, so the neutral is still 'live' into the amp. Sometimes it can carry enough voltage to give you a surprise, although it's very unlikely to be dangerous unless there's something major wrong with your supply wiring.

There's enough voltage on mine to trip the RCD to my workshop if I forget to fully unplug the amp and touch the neutral while working on it. Which is good, because it shows the RCD is very sensitive and is working correctly, but it can be annoying!

jpfamps

Personally if I am working on an amp, unless I am probing inside it when it's on, I like to unplug it from the mains, so I am 100% sure that there is no mains going to the unit.

That's why I like IEC sockets rather than captive leads as it's easy to see if the amp is unplugged.

jpfamps

thermionic said:

Ah right, of course - current dissipated as heat, I²R.

Pretty sure I read somewhere about leaving the mains lead plugged in but switched off to discharge filter caps, I should check the books I have...

You may have read this somewhere, but it's wrong (by the way most books I've read on guitar amps are riddled with technical errors).

Memphis

Re: insulating stuff -

I'm fairly confident of my soldering, so the connections between the IEC inlet, power switch, Tx and standby switch are unlikely to be issues when troubleshooting. Same with the connections to the output tx. I heatshrink all of these partly to neaten it up, partly to remove a few of the many lethal bits of an amp. It also means that if you have a thoughtless moment (most of the pros admit to them!) and try to fix something without unplugging, the discharge resistors will hopefully have drained all exposed connections - they won't drain the IEC and power Tx terminals!

martinw

Memphis said:

 It also means that if you have a thoughtless moment (most of the pros admit to them!) and try to fix something without unplugging....

Errr, no.

thermionic

Sorted out a couple of things while I'm waiting for my cab. Chickenhead knobs are for AC30s and this is more of a Marshall-flavoured thing. But the panel isn't brass/plexi coloured... so, silver knobs for the Jubilee look:

https://i.imgur.com/nY7SVZ6.jpg

Got myself a Greenback from the classifieds, described as VGC - can't argue with that:

https://i.imgur.com/q0BDb63.jpg

Had to test it right away - it's a bit ghettofabulous until I get the cab to put it all in:

https://i.imgur.com/pih3crG.jpg

thermionic

I should be picking this fine piece of furniture up this weekend:

https://i.imgur.com/WbdknS1.jpg

Danny1969

Nice job  

The other guitarist in one of my covers band built himself the SE5A previous version of that amp and made himself a 2 x 12" cab loaded with 2 Greenbacks. He gigg'ed it with me on Friday and it sounded fantastic, really organic crunch sound with a little home made Tube screamer for boost

If your mic'ed up those little amps are great to gig with as you can wind em up and get a glorious saturated crunch sound. If I didn't have the little HT5 I would make one

Gagaryn

Very nice!

thermionic

Well, now I can say that it really is finally complete. I'm just back from a little industrial estate nestled way up in the Swansea valley, home to AF Custom Cabs. It was good to meet Mark, even better to find out that he's a first language Welsh speaker like myself and have a chat about amps. I'd sent him a couple of photos of my chassis with every possible dimension marked up, so it was a matter of marking and drilling 4 holes before screwing it all back together. The cab is absolute quality, solid pine (not ply) and looks exactly like I wanted it. 

Here it is, the mini-bluesbreaker, Class 5-killer:

https://i.imgur.com/oPaxg8h.jpg

https://i.imgur.com/e2NMUEp.jpg

Misterg

Neat. Very neat!

(Mae o'n edrych yn dda iawn!)

Gagaryn

Very nice - you should be proud!