The 2150B has an inherent fault, and that is that the B+ and B- supplies run on adjacent tracks on the pcb, and any dust/smoke fluid/contaminants cause leakage currents.
The standard repair method for these amps is blanket small electrolytic change, blanket resolder of the boards, maybe change bias trimpots, and then clean the boards properly and then apply a conformal coating.
Do this, and typically you will be back to a fine amplifier.
Dan.
The standard repair method for these amps is blanket small electrolytic change, blanket resolder of the boards, maybe change bias trimpots, and then clean the boards properly and then apply a conformal coating.
Do this, and typically you will be back to a fine amplifier.
Dan.
What do you use for the conformal coating? I'm about to acquire one of these that's probably on its way out.
Buy Conformal Coatings Electrolube Transparent 200mL Aerosol Conformal Coating For PCBs, Acrylic Resin, -55 to +130C Electrolube ERHPA200HR online from RS for next day delivery.
There are other choices further down the page...silicone resin, poymer, etc.
Take your pick, I'd go for the silicone version.
Dan.
Until they warm up they sound like a bucket of shite.This preamplifier is beautiful
When warm, yes they sound quite pleasant.
Dan.
I'm sure there are plenty of alternates available to you more locally.
Comes down to it, just about any lacquer would do the job, provided that it it stable under high heat.
The silicone versions may sound nicer
.Dan.
I'm sure there are plenty of alternates available to you more locally.
Comes down to it, just about any lacquer would do the job, provided that it it stable under high heat.
The silicone versions may sound nicer
Dan.
Well, silicone enhances appearance in other applications; perhaps it will enhance sound in this one!
It might, and it might not.Well, silicone enhances appearance in other applications; perhaps it will enhance sound in this one!
Get the amp working right and then do an A/B and report back.
Dan.
Hi Ston_cold
I have a SM3 and 3150 amp. The SM3 has a blown channel. I would much appreciate if you could fwd me the manuals.
shaner@whitrose.com.au
I have a SM3 and 3150 amp. The SM3 has a blown channel. I would much appreciate if you could fwd me the manuals.
shaner@whitrose.com.au
just a silly question... I want to make sure how to measure the preamp properly with my multimeter. Per channel there are 5 TPs (test points/pins). How do I actually check if the voltages are correct? It states that voltages are measured to chassis (black probe on chassis while red probe on point after resistors I suppose?). What do I actually measure at the TPs?
Yesterday I received the Perreaux SM3 preamp from eBay and unfortunately the ALPS flex unit - 4 positions, 225mm long cable (sticker 509Y) is broken. I have been looking on the internet to find a replacement, but without success. Does anyone know where to get one or how to fix it?
