PCB heads which are so very neat and well designed under the lid ?

Telejester

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 ?

equalsql

It's not a head, but a combo, but my old Peterson P100G is a lovely example of well (hand) built solid state design:

https://image.space.rakuten.co.jp/lg01/75/0000391075/42/img252dc080zikczj.jpeg

timmysoft

I don't think the DSL is that bad to be honest and the ones i used to tour held up to the task just fine (without flight cases!)

 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!

ThePrettyDamned

timmysoft said:

I don't think the DSL is that bad to be honest and the ones i used to tour held up to the task just fine (without flight cases!)

 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). 

Telejester

Ive owned a pre 84 50 watt jcm800 which was bulletproof and a very neat design undrr the hood, ive owned a dsl50 and dsl100 which were horrendous under the hood and both blew output transformers, needless to say both those heads got quickly sold on.

Telejester

When i think awful pcb design one that comes quickly to mind is the shitty folding pcb in a peavey classic 30, what the hell where they thinking?

ecc83

 "Blackstar apparently made fixes on all future runs"

Yes, they did.

Dave.

Teetonetal

I had to replace the jack socket on my pleximan (drummer tripped on the guitar lead and destroyed the thread holing it on to the chassis. It's a really neat and tidy build on what to my untrained eye looks like a very thick PCB.

From google:
https://goo.gl/images/1C2jMp

digitalscream

JCA22H seems pretty good to me:

http://img.photobucket.com/albums/v212/fastredponycar/Guitar/Jet City JCA22H/untitled-2181.jpg

Danny1969

Looks don't tell you a lot to be honest in terms of neatness, what's more important is if the design of the PCB is  able to cope with any HT voltages in terms of track spacing, PCB insulation .... has much thought gone into making sure higher current /hotter  components don't desolder themselves or fry adjacent components, is the PCB properly supported of does it bend like a diving board. Has it got through hole plating etc

In terms of the actual PCB quality I think Mesa are the highest quality I've seen in a guitar amp ...  

Gassage

Open a @ThorpyFX ; Pedal and then you'll see beauty.

ICBM

Danny1969 said:

Looks don't tell you a lot to be honest in terms of neatness, what's more important is if the design of the PCB is  able to cope with any HT voltages in terms of track spacing, PCB insulation

This is the most serious design fault with the Marshall DSL/TSL series. Arcing between tracks or through the thickness of the board is one of their more common problems.

Danny1969 said:

has much thought gone into making sure higher current /hotter  components don't desolder themselves or fry adjacent components

This is a common problem too, in particular with amps, like many Fenders, which use Zener diode shunt-regulation for the lower-voltage supplies.

Danny1969 said:

is the PCB properly supported of does it bend like a diving board. Has it got through hole plating etc

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.

Danny1969 said:

In terms of the actual PCB quality I think Mesa are the highest quality I've seen in a guitar amp ...  

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.

TimmyO

Soldano SLO100 had a good reputation for this iirc

jpfamps

THD are best made PCB amps I've seen.

2 mm PCBs with 4oz copper.

Sassafras

An amp the size of an MXR pedal.
  

Telejester

Just saw a pic of the hamstead 20 internals, thats the way to do it, makes the dsl100 look like someone threw a chow mein under the lid.

ThePrettyDamned

Telejester said:

Just saw a pic of the hamstead 20 internals, thats the way to do it, makes the dsl100 look like someone threw a chow mein under the lid.

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...

welshboyo

A tech that worked on my Bogner said it was a well laid out/built PCB.

@ICBM I seem to remember you working on one of these - agree?

imalrightjack

Mesa cram quite a lot into the Mark V: 25

ICBM

welshboyo said:

A tech that worked on my Bogner said it was a well laid out/built PCB.

@ICBM I seem to remember you working on one of these - agree?

From memory, yes - although there was something else about the Shiva I worked on that I wasn't so keen on… but I forget what now!

imalrightjack said:

Mesa cram quite a lot into the Mark V: 25

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 .

welshboyo

@ICBM probably the dull "off-mainboard" Valve Heater Power Supply...

But in saying that I've gone through 2 so glad it was off board and was an easy replace!!