I have been enjoying my pristine condition Levinson 332 power amp for a couple years. It was serviced last year by a knowledgeable tech in Austin and has sounded wonderful since the cap replacement and adjustments.
I finally got my hands on a No 380 preamp to pair with my amplifier. The comm port between the two worked perfectly. Between the conveniences of the 380's remote control and the sweet sounds of the ML combo I was in stereo heaven.
That is until I plugged in a newly purchased pair of Klipsh Heresy I's that I planned to upgrade. I didn't test the speakers before attempting to listen to them and obviously there is a short in the crossover or something came loose in shipping. When I plugged them up and turned the system on I got about 5 sec of barely audible music. Without thinking, I slowly increased the volume. Immediately there was a quiet small pop noise and then nothing.
I have only been into DIY a short time and haven't done much more than TT mods or bookshelf building. I am addicted to the hobby, despite my inexperienced, but I am determined to get my beloved amp back.
From my blunder, is there something obvious that I should check in the amp? I have found all the schematics so kindly posted from user Levinson Mark for the 332. I dug up a wire resistor replacement instruction guide elsewhere. From the schematics and my basic base of knowledge, I believe I can locate the F301, F302, and F303 30amp fuses.
Before I open her up, I wanted to see if anyone would push me towards the most obvious source of the problem.
I am skeptical that either the fuses or resistors would have blown from a shorted bookshelf speaker, but honestly I am not very confident.
Anyone with pictures of the insides, an idea of what I may have blown, or any suggestions to get me back up and listening would be greatly appreciated.
Thank you in advance for any assistance.
I finally got my hands on a No 380 preamp to pair with my amplifier. The comm port between the two worked perfectly. Between the conveniences of the 380's remote control and the sweet sounds of the ML combo I was in stereo heaven.
That is until I plugged in a newly purchased pair of Klipsh Heresy I's that I planned to upgrade. I didn't test the speakers before attempting to listen to them and obviously there is a short in the crossover or something came loose in shipping. When I plugged them up and turned the system on I got about 5 sec of barely audible music. Without thinking, I slowly increased the volume. Immediately there was a quiet small pop noise and then nothing.
I have only been into DIY a short time and haven't done much more than TT mods or bookshelf building. I am addicted to the hobby, despite my inexperienced, but I am determined to get my beloved amp back.
From my blunder, is there something obvious that I should check in the amp? I have found all the schematics so kindly posted from user Levinson Mark for the 332. I dug up a wire resistor replacement instruction guide elsewhere. From the schematics and my basic base of knowledge, I believe I can locate the F301, F302, and F303 30amp fuses.
Before I open her up, I wanted to see if anyone would push me towards the most obvious source of the problem.
I am skeptical that either the fuses or resistors would have blown from a shorted bookshelf speaker, but honestly I am not very confident.
Anyone with pictures of the insides, an idea of what I may have blown, or any suggestions to get me back up and listening would be greatly appreciated.
Thank you in advance for any assistance.
Look at the speaker wire connections for shorts, both at the amplifier and the speaker.
Use a DVM to measure the (disconnected) speaker terminals for a short.
Then look for blown fuses, with the amplifier power cord unplugged.
It's possible that the protection circuits triggered, and there is no damage.
Use a DVM to measure the (disconnected) speaker terminals for a short.
Then look for blown fuses, with the amplifier power cord unplugged.
It's possible that the protection circuits triggered, and there is no damage.
This sucks so bad. I know how good that ML stuff sounds, my brother has three monoblock amps and a ML pre-amp. I have a pretty nice system too, a Proceed amp made by Mark Levinson, but his stuff still sounds better, which I was actually pretty surprised by. Any way, I know this is no help, other than moral support. I hope you get it fixed, and hopefully it's something pretty simple!
I WILL get it fixed. I WILL do my best to fix it myself.
Rayma, I am on it now. First step finished. I got the 180 lbs thing out of its shelf. Now I turn on it on its side to expose its resistor trap door. Finally remove the top panel, grab my MM, and go to town.
Clauses, moral support is only appreciated less than possible solutions, but still completely necessary.
Time to become a man.
Rayma, I am on it now. First step finished. I got the 180 lbs thing out of its shelf. Now I turn on it on its side to expose its resistor trap door. Finally remove the top panel, grab my MM, and go to town.
Clauses, moral support is only appreciated less than possible solutions, but still completely necessary.
Time to become a man.
Attachments
Below is am pasting a reply to all DM from generatorlabs on Audiogon. He rebuilt a completely trashed No 332 a while back and knows the machine in and out.
As an aside, his rehab post includes pics of the most beautiful power amp I've ever seen. He achieved this by removing the paint and pollishing the covers on his No 332. I'm serious, it makes an already very attractive amp look as good as any amp I've ever seen. ML really missed an opportunity by painting the chassis.
My responses to suggestions and potential fixes. I believe I added in enough context:
1. No. No sound from working / tested speakers when powered up and playing music.
2. Yes. I hear the relays closing as the power builds up before being allowed into the critical components. Clicks and lights work as normal.
3. I believe the relay click count is 5, but I'm way too far away from the power source to consider testing it to verify.
4. Yes. LED status on the front of the 332 seems normal. The light diodes were strong, steady, and lit up in the correct order.
Additionally, since I recently aquired a No 380 pre, I whipped up a cat-12 comm port cable (from pre to power). It brings the system from OFF to ON to Standby without issue. I read that if a protection circuit or other error was detected within the pre or power, I would be given a code on the preamp LCD screen. Nota. It even quickly flashes "Errors 0" on boot-up.
5. As suggested, I will look into what a "Safty Interlocks" are and where they exist in the system.
6. As suggested, I will find out where the "Output Transistors" live and make sure the are within tolerance, if applicable. 😉 It sounds like you are suggesting that a noise would be typical if one of these failed. However, it "failing open" could result in a quiet death.
7. I will check, with my eyes and nose, for bad main caps. Paying special attention to the screw terminals for erosion.
8. The amp was warm when it bit the dust. I had been listening to the system for many hours when I got the the itch to try the Heresy I's that had just arrived. The system was only off long enough to swap speaker cables and turn it back on.
9. It was supposed to be biased when it was serviced only about 2 years ago. The owner at that time provided the $1600 service receipt. I believed all signal path caps and biasing had both been done.
That's it. Thank you so much, and wish me luck.
sigmafia
As an aside, his rehab post includes pics of the most beautiful power amp I've ever seen. He achieved this by removing the paint and pollishing the covers on his No 332. I'm serious, it makes an already very attractive amp look as good as any amp I've ever seen. ML really missed an opportunity by painting the chassis.
My responses to suggestions and potential fixes. I believe I added in enough context:
1. No. No sound from working / tested speakers when powered up and playing music.
2. Yes. I hear the relays closing as the power builds up before being allowed into the critical components. Clicks and lights work as normal.
3. I believe the relay click count is 5, but I'm way too far away from the power source to consider testing it to verify.
4. Yes. LED status on the front of the 332 seems normal. The light diodes were strong, steady, and lit up in the correct order.
Additionally, since I recently aquired a No 380 pre, I whipped up a cat-12 comm port cable (from pre to power). It brings the system from OFF to ON to Standby without issue. I read that if a protection circuit or other error was detected within the pre or power, I would be given a code on the preamp LCD screen. Nota. It even quickly flashes "Errors 0" on boot-up.
5. As suggested, I will look into what a "Safty Interlocks" are and where they exist in the system.
6. As suggested, I will find out where the "Output Transistors" live and make sure the are within tolerance, if applicable. 😉 It sounds like you are suggesting that a noise would be typical if one of these failed. However, it "failing open" could result in a quiet death.
7. I will check, with my eyes and nose, for bad main caps. Paying special attention to the screw terminals for erosion.
8. The amp was warm when it bit the dust. I had been listening to the system for many hours when I got the the itch to try the Heresy I's that had just arrived. The system was only off long enough to swap speaker cables and turn it back on.
9. It was supposed to be biased when it was serviced only about 2 years ago. The owner at that time provided the $1600 service receipt. I believed all signal path caps and biasing had both been done.
That's it. Thank you so much, and wish me luck.
sigmafia
When i test the terminals with a Digital Volt Meter, is there any ideal reading I'm looking to get, or is continuity enough? I am very aware this is rookie stuff, but I am a rookie.