Wayniac
Active Member
About 15 years ago, in a bar in South Korea, a colleague and I discussed audio equipment and he said he owned a pair of McIntosh MC-30s. I offered to buy them, and he replied, "Hell no, you pay for shipping and they are yours.". Needless to say, I bought him a beer. 
Some time later, I returned home to California, he returned to Massachusetts, and a box showed up at my job. Yep, it was the amps...........I had forgotten all about it, he hadn't. They were non-functional, but I have skills.
I finally got around to repairing them while restoring my JBL L100ts at the same time. I just finished the second amplifier on Thursday. I replaced all resistors and capacitors in the amps. The resistors are all metal film 1% parts, except of course, the power supply resistors which are 1% wirewound. Signal capacitors are teflon or polypropylene. The polys are Electrocubes, also used by Audio Research, Counterpoint and Paragon. The teflons are russian mil-spec FT-3s. Signal wire installed by me is 18 gauge solid silver with teflon insulation. Silver solder was used exclusively for every joint I touched. Keep in mind, much of the original wiring remains untouched. The selenium rectifier was replaced with a diode and the power supply has a bit more capacitance. The AC input now has power-up surge suppression.
MC-30 Rebuild Thread Here.
The JBLs, I bought new about 25 years ago. I drove them with a Yamaha C-80/M-80 combo for years. They needed some TLC. I sent the bass drivers out for refoaming at a local JBL service center. They were returned, in short order, with quality workmanship. I made my own crossover PCBs by copying JBLs design, resizing it to fit larger/more capacitors on an 8" by 10" copper clad board. I used the original coils, Solen and Dayton caps, with new resistors, and silver solder.
L100t Crossover Thread Here.
I connected the amps and JBLs to a sony CD player. The results were astounding. I never thought the JBLs had it in them. It gets better.
My wife is out of town and my best friend came over to stay the night. He too, has a very nice system, B&W 801 Matrix, Jeff Rowland Model 5, Counterpoint pre-amp. He only spins vinyl now and finds digital sources "annoying". He too, brought me a gift. A Theta DS Pro Prime II DAC. He says "I think it serves a better purpose here". You see, it was connected to his patio speakers. Unbelievable. Needless to say, I handed him a beer.
So, how does it sound? I lack the adjectives to describe it. Airy, unfettered, spacious, detailed, coherent. The detail and nuance are very involving. Wide and tall soundstage, some depth. Low level listening is a joy. Louder levels? More of the same. No edginess or fatigue inducing harshness at all. We listened for hours in absolute amazement. I just never thought the JBLs had it in them. Theta DAC, MC-30s and L100ts are a synergistic combination, guaranteed to amaze.
Be kind to everyone you meet, as they may give you your best stereo ever.
Some time later, I returned home to California, he returned to Massachusetts, and a box showed up at my job. Yep, it was the amps...........I had forgotten all about it, he hadn't. They were non-functional, but I have skills.
I finally got around to repairing them while restoring my JBL L100ts at the same time. I just finished the second amplifier on Thursday. I replaced all resistors and capacitors in the amps. The resistors are all metal film 1% parts, except of course, the power supply resistors which are 1% wirewound. Signal capacitors are teflon or polypropylene. The polys are Electrocubes, also used by Audio Research, Counterpoint and Paragon. The teflons are russian mil-spec FT-3s. Signal wire installed by me is 18 gauge solid silver with teflon insulation. Silver solder was used exclusively for every joint I touched. Keep in mind, much of the original wiring remains untouched. The selenium rectifier was replaced with a diode and the power supply has a bit more capacitance. The AC input now has power-up surge suppression.
MC-30 Rebuild Thread Here.
The JBLs, I bought new about 25 years ago. I drove them with a Yamaha C-80/M-80 combo for years. They needed some TLC. I sent the bass drivers out for refoaming at a local JBL service center. They were returned, in short order, with quality workmanship. I made my own crossover PCBs by copying JBLs design, resizing it to fit larger/more capacitors on an 8" by 10" copper clad board. I used the original coils, Solen and Dayton caps, with new resistors, and silver solder.
L100t Crossover Thread Here.
I connected the amps and JBLs to a sony CD player. The results were astounding. I never thought the JBLs had it in them. It gets better.
My wife is out of town and my best friend came over to stay the night. He too, has a very nice system, B&W 801 Matrix, Jeff Rowland Model 5, Counterpoint pre-amp. He only spins vinyl now and finds digital sources "annoying". He too, brought me a gift. A Theta DS Pro Prime II DAC. He says "I think it serves a better purpose here". You see, it was connected to his patio speakers. Unbelievable. Needless to say, I handed him a beer.
So, how does it sound? I lack the adjectives to describe it. Airy, unfettered, spacious, detailed, coherent. The detail and nuance are very involving. Wide and tall soundstage, some depth. Low level listening is a joy. Louder levels? More of the same. No edginess or fatigue inducing harshness at all. We listened for hours in absolute amazement. I just never thought the JBLs had it in them. Theta DAC, MC-30s and L100ts are a synergistic combination, guaranteed to amaze.
Be kind to everyone you meet, as they may give you your best stereo ever.
Last edited:
