djduck
Active Member
Picked up this interesting piece today for €40, or about 50 American.
It's a professional rackmount power amplifier made in Bulgaria, in the early 80's, by a company called Resprom. Model EMS 1511. Part of the EMS 1000 set. Dual mono, 100w per channel. Originally designed for 100v commercial installs in malls, arenas, schools, bus stations, etc... but this one has it's transformers removed and happily operates with regular 4-16ohm speakers.
Something I found interesting is that while the pre-amplifer is biased in class A (there is quite a bit of heat comping from those transistors! ), the power amplifier is biased in class BC, something I have never hear of until now.
I bought it use as an amp for PA speakers, but I can't, for one simple reason:
It sounds WAY too good. Seriously. I have it playing background music with my B&W DM310s hooked up and laptop as source, and it sounds just brilliant. And that is with the original 30 year old electrolytics! This thing just went way beyond my expectations, has to be hear in order to be believed Very good bass, not boomy but very tight and punchy and somewhat "fat" sounding, if that makes sense, very clear and detailed mids and crisp highs. Overall just very musical and detailed. So far I have tried jazz, rock, pop, techno and dubstep with this and it's perfect for every genre! My B&Ws have never sounded this amazing!
I'm going to be taking it apart, cleaning everything, repairing cracked solder joints, maybe a few more things. And it's definitely going to have a phono pre installed! If anyone is interested, I could post some pictures here as I make progress
It's a professional rackmount power amplifier made in Bulgaria, in the early 80's, by a company called Resprom. Model EMS 1511. Part of the EMS 1000 set. Dual mono, 100w per channel. Originally designed for 100v commercial installs in malls, arenas, schools, bus stations, etc... but this one has it's transformers removed and happily operates with regular 4-16ohm speakers.
Something I found interesting is that while the pre-amplifer is biased in class A (there is quite a bit of heat comping from those transistors! ), the power amplifier is biased in class BC, something I have never hear of until now.
I bought it use as an amp for PA speakers, but I can't, for one simple reason:
It sounds WAY too good. Seriously. I have it playing background music with my B&W DM310s hooked up and laptop as source, and it sounds just brilliant. And that is with the original 30 year old electrolytics! This thing just went way beyond my expectations, has to be hear in order to be believed Very good bass, not boomy but very tight and punchy and somewhat "fat" sounding, if that makes sense, very clear and detailed mids and crisp highs. Overall just very musical and detailed. So far I have tried jazz, rock, pop, techno and dubstep with this and it's perfect for every genre! My B&Ws have never sounded this amazing!
I'm going to be taking it apart, cleaning everything, repairing cracked solder joints, maybe a few more things. And it's definitely going to have a phono pre installed! If anyone is interested, I could post some pictures here as I make progress