At the weekend I had a peer under the lid of a marshall dsl100 head and woof !!! What a frickin mess that thing looks, not radically different looking from taking every wire, chip and component and throwing it under the lid, so very disappointing. By contrast a pre 84 jcm800 head i used to own was well tidy under the lid.
Internally the best ever pcb layout i ever saw was on a hiwatt head, i mean that thing was as neat as a superb example of ptp wiring, just fantastic . I applaud laney for chassis mounting the power tubes on their studio l5 head ,when i spoke to martin kidd at victory as to why the sheriff 22 comes with board mounted power tubes he said cost, i mean if laney can do it on the studio l5..........
What pcb heads have you seen where its obvious a lot of thought and care has gone into its design and board layout ?
Comments
https://image.space.rakuten.co.jp/lg01/75/0000391075/42/img252dc080zikczj.jpeg
The worst built i've come across was the Blackstar series 1 amps. The s1 200 had wobbly pots, was poorly balanced during lifting and gave up working just 15 minutes into its first outing. The band i used to tech for had a few s1 50's go down too, the heads were put on end in the tour bus and by the next day the chassis had bowed around the transformers and caused some pretty irreparable damage. The back ups on that tour were a DSL50 and a Hiwatt HiGain 50, it really says something if the hiwatt is more reliable than the Blackstars. I rate their HT series of amps much more highly, they seem more solid and sound much better!
I have heard from a local shop that initial s1 amps were basically screwed up. Blackstar apparently made fixes on all future runs.
Obviously, no proof of this. The ones I've tried sounded good (if not breathtaking) and felt solid, no nasty wobbles for sure. Obviously, I wouldn't expect that to change your opinion either.
I looked inside my peavey bandit and that was surprisingly neat. My old Laney lh50 was also very tidy, it's a vc50 in head form I think. Brilliant sounding and utterly reliable for me, bar when it blew power valves once and a preamp valve went down (stopping the drive channel working - clean was fine).
"Blackstar apparently made fixes on all future runs"
Yes, they did.
Dave.
From google:
https://goo.gl/images/1C2jMp
http://img.photobucket.com/albums/v212/fastredponycar/Guitar/Jet City JCA22H/untitled-2181.jpg
In terms of the actual PCB quality I think Mesa are the highest quality I've seen in a guitar amp ...
*An Official Foo-Approved guitarist since Sept 2023.
This is a common problem too, in particular with amps, like many Fenders, which use Zener diode shunt-regulation for the lower-voltage supplies.
In many ways that doesn't matter, as long as large/heavy/hot components aren't mounted on it. eg the old Marshall JMP PCB isn't particularly great quality - quite thin and not through-plated - but faults on it are extremely rare because it only carries small, light components and it's not attached to anything else which can flex it... the pots and jacks are off-board.
I would agree with that, and they also mount the pots and jacks offboard while allowing the PCB to float slightly on nylon standoffs, so it's not under much stress even though the preamp valves are usually mounted on it.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
THD are best made PCB amps I've seen.
2 mm PCBs with 4oz copper.
An amp the size of an MXR pedal.
Must admit, though, when I tried one (admittedly a few years back) it didn't really blow me away sound wise.
To be fair though, the more expensive an amp is, the more I expect it to blow me away so I was being hard...
@ICBM I seem to remember you working on one of these - agree?
My band, Red For Dissent
I'm much less of a fan of these ribbon connectors in the newer Mesas. I've had a couple of repairs where the fault was caused purely by bad contacts in these - actually between the wire and the connector, rather than between the connector and the board pins.
I am not really a fan of push-connectors at all though, as you probably know .
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
But in saying that I've gone through 2 so glad it was off board and was an easy replace!!