Count Bassie Posted March 29, 2023 Author Posted March 29, 2023 Plywood this weekend, and a trip to my friend's panel saw. Quote
Count Bassie Posted January 20, 2024 Author Posted January 20, 2024 Life takes you down the river... Have *not* gotten to this! But this coming week I've got an appointment with a friend's panel saw... 3 Quote
Count Bassie Posted March 22 Author Posted March 22 (edited) There have been many detours and life has thrown into the path, but finally this is started in earnest. @Matt P, I took your drawings to the shop yesterday and cut me some plywood. Glue, screws and clamps tonight... Got my tech guy interested, off to the bench soon as it's fitted to the sleeve. Edited March 22 by Count Bassie 1 Quote
Stub Mandrel Posted March 22 Posted March 22 On 04/08/2022 at 01:51, DGBass said: As far as schematics go, the old MkII and MKIV GP7/11 versions don't seem to be available anywhere I can find. The Power amp chassis though is pretty much the same as in the more readily downloadable (online) MKV AH250/350/500 schematic so that at least will make any maintenance on the power section possible. I rebuilt a MKV AH250 during lockdown and the amp section does hang "upside down' normally and there are three cables from it to worry about. The main power amp signal cable and power feed for the GP11 front panel pre-amp which is usually a square plastic multi plug that can only fit one-way and the two 110V blacklight connecting plugs. I messed about with trying to fit mine all in a 3U or 4U flight case but it was easier fixing up the original 3U wooden sleeve despite it being damaged. The power sections are heavy beasts and the 4U case I intended to use wasn't structurally heavy duty enough to cope with having the power amp chassis bolted in upside-down like it is as standard. I tried and it rattled in the case a lot. 3U cases seem much harder to source these days except if you are willing to pay a bit more for one or to have your AH250 GP11 professionally installed in a custom made rack case. They are killer amps and nothing much goes wrong with them apart from worn graphic sliders especially if they are the earlier white plastic ones. The blacklight doesn't usually give much problem either as long as the 110v tube starter is replaced periodically and of course the blacklight tube does wear out eventually after 30 or so odd years of service 🙂 I suppose cosmetics don't matter too much as long as you are happy with the performance aspect. It's always good though to see one of these on stage with that blacklight glowing away and illuminating the green goodness of the pre-amp. You know you've arrived when you feel one of these AH units behind you on stage. GP11 schematic here. Fixed mine using it. trace-elliot_GP11-AH350-AH500-MK-V-BASS.pdf 1 Quote
Count Bassie Posted March 22 Author Posted March 22 1 hour ago, Stub Mandrel said: GP11 schematic here. Fixed mine using it. trace-elliot_GP11-AH350-AH500-MK-V-BASS.pdf 933.98 kB · 19 downloads Thank you! That should be very helpful, yessir. Quote
bremen Posted March 22 Posted March 22 Later versions show a power amp stage that's virtually identical save for some small caps on the gates of the output devices. I wonder if they were added to fix a stability issue? None of these have speaker protection other than a fuse. This suggests that they never go DC, I know they have a great reputation for reliability, has anyone ever had a Trace amp go bad and kill their speakers? Happened to me once (not with a Trace amp), was a very upsetting experience. Quote
Count Bassie Posted March 23 Author Posted March 23 Well sock it to me! She fits. Gluing 'er up and setting screws, off to the bench... You may notice the butt-joint at bottom-right. Somehow I made a wrong cut on the top and bottom pieces, but has enough left over so I could adjust the width (height, properly oriented) of that side. The shape is still true, it just looks wonky. Some Epoxy and Duratex'll hide that badge of shame... 🙂 4 Quote
Pea Turgh Posted March 24 Posted March 24 Nice job! I have a naked head from a 715s combo to house before sending off to an amp doctor. Just need some ply and a couple of hours. Love making stuff out of wood! 1 Quote
Count Bassie Posted March 24 Author Posted March 24 1 hour ago, Pea Turgh said: Nice job! I have a naked head from a 715s combo to house before sending off to an amp doctor. Just need some ply and a couple of hours. Love making stuff out of wood! Thanks! I was very much already put at ease with this when I saw it was a nearly-snug fit. Just enough room to get it in there without a serious fight, and a little space above for air. Yeah wood is cool to work with, especially when it's your own project. 😎 No more combo? I've subbed that, took a Peavey Combo 300 and made it head-only, because of the weight. I ended up loaning it to a guy and never saw it again. Teach me to be a nice guy! That was a good solid gig amp. Quote
Count Bassie Posted Thursday at 03:33 Author Posted Thursday at 03:33 Drilled and parts set in place. To the bench this weekend, and I'll have a couple weeks to make the sleeve look like something. 2 Quote
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