Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Platefire on April 05, 2023, 11:29:56 am
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I have agreed to take a look at a Blackstar 100 watter that I'm told don't sound good anymore.I didn't hesitate agreeing to take it on because it belongs to my Grandson.
Even though I don't know the model or details of the amp yet as it hasn't been delivered tome yet, I have done a little research on Blackstar. So from what I've learned, if it's correct, Blackstar doesn't provide schematics to customers or techs. That you have to be an authorized dealer to get repair support?
So as I researched the tech repair trail of repair work done by un-authorized techs, the story sounds pretty grim. So I'm not wanting to start a bash Blackstar thread. i am wanting to hear
from those who had experience working on these amps, some tips or advice. Thanks, Platefire
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I haven't ever played through one or even seen one in person, but these videos might be helpful.
Pretty sure I have watched some of them & they may give you an idea of what you are looking at.
PSIONIC/ BLACKSTAR (https://www.youtube.com/@psionicaudio/search?query=blackstar)
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Thanks, I watched them. The external bias adjustments on the Club 40 was different, adjusting between the green and red lights. After getting voltage readings, doing the math and setting to the desired mA for desired dissipation, how in the world would you know what kind of bias you got setting between the lights? Of course it's a pre-determined by Blackstar cool/warm/hot setting--who knows? Kind of like Boogie. Anyway that stuck out at me.
The hardest part for me is dealing with PCB :icon_biggrin:
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Since its your grandson, perhaps put it to him that the cheap PCBs inside it are way past the bargain Chinese warranty period and use-by date, but if he wants to pay for abc parts you can gut it and convert it to some other amp using a commercially available turret or eyelet board and new tubes sockets and controls? Parts (excluding any reusable transformers and tubes) might come to $xyz, but you'll chip in some spare bits and bobs you've got lying around. Then we can all gather around your project on this here Hoffman forum and have a good ole chit-chat. :-)
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Sounds good! He is a very talented player and has amazed me many a time. I'll just have to follow this out, see where it goes and do the best I can for him and his amp.
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A while back, one of my friends teen boy had his black star stop working
I reluctantly told them I would look at it.
It was an impossible task it seemed after having a look at the PC board with surface mount components
Luckily, I saw a Youtube video of the same amp with the same problem
Right after the input jack there is a surface mount inductor
It was blown in half
I ended up just running two jumpers across the board and the amp worked again
I pity any repairman that has to work on these modern amps
Here's a shot of the two jumpers I installed.
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Since its your grandson, perhaps put it to him that the cheap PCBs inside it are way past the bargain Chinese warranty period and use-by date, but if he wants to pay for abc parts you can gut it and convert it to some other amp using a commercially available turret or eyelet board and new tubes sockets and controls? Parts (excluding any reusable transformers and tubes) might come to $xyz, but you'll chip in some spare bits and bobs you've got lying around. Then we can all gather around your project on this here Hoffman forum and have a good ole chit-chat. :-)
Unless it’s one of their handwired tube amps?
https://blackstaramps.com/artisan-series/ (https://blackstaramps.com/artisan-series/)
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I pity any repairman
late 90s we started getting surface mounted PCBs from the oem's, I knew it was the dead-sentence for in-house folk like me.
I went to the boss, said i need $5k for a decent repair station for surface mount repair, he said no, I said YEESSSS, thanks boss.
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Doug, that's a clean jumper repair. Looks like it should of been there all along. I've done a few PCB board repairs over the years including installing a couple of jumpers. It's way out of my comfort zone and when I put it back together and it works, I breath a big sigh of relief and ready to get it out of my presence. I wish I could have a more optimistic attitude about working on them but I'm not there yet
tubeswell---Those Artisan's looks pretty good. I was looking for a gut shot but didn't see any. I'm pretty sure his is the PCB version because his Dad bought it and don't think he would spring for hand wired. Hopefully it can very simply be brought to 100%--if not, ya'll gonna have to come up with some stuff to get me through this--who in his right mind can deny his Grandson
shooter---Truthfully they are disposable amps. For the non-tech guitar player, as long as they are under warranty and no issues, great deal! but once you have major problems, warranty's gone, the repair bills can stack up to be not feasible to keep it going. Then guys like us buy them, gut it and build a P to P amp out of it that can last forever:>)---well long as Doug keeps selling us parts
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I reverse engineered a pair of the Artisan series amps over a decade ago. They were decent sounding amps IMO. If it's an Artisan 100, then it's worth the time to reverse engineer it. If it's one of the "modern" PCB units with every bell and whistle, surface mount components, the issue isn't easily remedied/found, then gut the POS and build a Soldano SLO clone in the chassis.
The Artisan series amps were hand wired in Korea, but I read somewhere that now, of course, built in PRC. The Artisan 30 were noted to red-plate EL84s, at the time I had the pair there was lots of reading in cyberspace on that topic, the one Artisan 30 I had on my bench was afflicted with said.
--Pete
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I have to admit, I do have two PCB amps. A Mesa Boogie Rocket 440 and a SS Crate GTX15 practice amp. So far no major problems with them. :icon_biggrin:
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I have to admit, I do have two PCB amps
I have a complete chassis out of a Beringher Thunderbird practice amp (left over after gutting the cab to use it for a small tube amp), which will make a handy listening amp tool one day. And an old 300W Bass Amp head which just sits around out of nostalgia for my wild years when I had it in a gigging band in the early 80s.
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It's amazing what we hold on to and let go. The only amp I have from my wild years is a
1975 Peavey Pacer. It was a SS amp that I converted to a DR a few years back. I sold the PCB board out of it to some one on this forum, but I can't remember who? It was my first SS amp. It had a MV and an OD knob that was switchable. That thing would krank out some pretty mean distortion and was a loud 45 watts. I blew out several speakers on that one.