Supro Black Magick head & cab- slight worries

JamesSGBrown

Evening all!

I'm considering picking up the Supro Black Magick head & 1x12 as I can get them at a pretty great price.

I love the way this amp sounds and looks, but frankly I'm slightly concerned as i've read some things about the build quality that are less than favourable. Tube sockets mounted to the PCB etc. I do intend to gig this amp and push it quite a bit with pedals etc. I'm not concerned about PCB vs Handwired etc- but I would love to hear people's experiences with these new Supros. Are they up to gigging without any overheating problems or anything? My other amp is a Traynor which is solid as a rock, and I hate having 'technical anxiety' whenever I play shows.

Cheers!

thecolourbox

A lot of pros use Supro I think, however a lot of pros also have amp techs to sort such things out so that's not a great indicator.

Love Supro amps sounds though, would be very keen to get the Thunderbolt or Black Magic if I ever needed an amp but they tend to be priced out of my league

matone

When in doubt,both feet out ! lol.
What i`ve picked up is that they`re very cheaply constructed and consequently overpriced .

ICBM

They’re not *very* cheaply constructed, but they’re still overpriced for what they are. There’s nothing wrong with the basic build quality or method, although it’s definitely not ‘high end’.

I’ve worked on one (Thunderbolt+) with a fault caused by poor assembly rather than bad build quality, although the design was a slight contributing factor.

PCB-mounted valve sockets are not an issue as long as they’re done right (which these ones are), despite that being a popular ‘test of quality’. There are amps with poor chassis-mounted sockets too... and some with bad PCB-mounted ones, including the Traynor YCV20.

JamesSGBrown

ICBM said:

They’re not *very* cheaply constructed, but they’re still overpriced for what they are. There’s nothing wrong with the basic build quality or method, although it’s definitely not ‘high end’.

I’ve worked on one (Thunderbolt+) with a fault caused by poor assembly rather than bad build quality, although the design was a slight contributing factor.

PCB-mounted valve sockets are not an issue as long as they’re done right (which these ones are), despite that being a popular ‘test of quality’. There are amps with poor chassis-mounted sockets too... and some with bad PCB-mounted ones, including the Traynor YCV20.

The RRP is ridiculous I agree. I'm able to get one at essentially trade price, which is what is peaking my interest. 

When you say poor assembly do you think it was an issue isolated to the particular amp you worked on, or was it indicative of a general approach do you think?

ICBM

JamesSGBrown said:

When you say poor assembly do you think it was an issue isolated to the particular amp you worked on, or was it indicative of a general approach do you think?

That particular fault will be common to all that model from what I've seen in pics. The problem was that the shaft of the power selector rotary switch was not cut down correctly, leaving the knob 'floating' in space. A bump on the top of the knob, instead of being stopped by the threaded bushing, pushed the shaft down into the rotary switch, which was a generic plastic type. The casing opened up slightly, the rotor was then able to jump the end stop, and connect one of the contacts to something it shouldn't have and blow the fuse. Luckily there was no other damage and simply re-assembling the switch and cutting the shaft down properly fixed it.

Either a better-quality metal rotary switch, or more care in proper assembly - twenty seconds to cut the shaft down to the right height - would have stopped it happening in the first place.

If the trade price is typically 2/3 of RRP it's not too bad, but I certainly wouldn't want to pay more than that. They're very nice-looking and sounding amps (although not like the originals really) but the build quality is frankly not a lot better than a Chinese Epiphone amp.

bbill335

bit of a cautionary facebook thread here

ICBM

bbill335 said:

bit of a cautionary facebook thread here

 
Ouch. That's not good - it looks like the resistor has cooked the board, presumably because of the usual American habit of not fitting HT fuses to their amps... I can't remember if these have them or not, but from the damage I'm guessing not.

NB, that's not a fault with the PCB-based design by itself. It's that high-power resistors should not be mounted tight to the board, and adequate fusing should be used.

This can happen to expensive hand-wired amps too, if the fusing isn't done properly.



That's a Fender Custom Shop Eric Clapton Twinolux - note that the eyelet board is burned under the resistor as well as the valve socket being incinerated... and that's a ceramic socket.

The original cause of this - and probably the Supro damage above - was a valve failure, but since that can happen to any valve amp, they should be designed to protect themselves if it happens!