Best Of
Re: Thinking about trying a tube amp. Thoughts.
Watts are overrated.
Tom
Too true. I just repaired a Mark Levinson 331, and I’ve been A/B testing it against my Carver Silver 9t pair. The carvers put out a solid 600 wpc, and the Levinson is rated at 100 wpc. There is zero difference in either of these in their ability to drive my NHT 3.3 speakers (which are somewhat difficult to drive). There are MANY differences in the amps otherwise, but you would never guess there is a power disparity between them by listening.
daddyjt
2 ·
Re: Mark Levinson 331 amplifier repair.
Posted Monday at 11:32 AM
Standing back with my arm outstretched, fire extinguisher on the table (I’m not kidding), I tapped the power button this morning. Standby mode activated without a problem. Next, the moment of truth…
a second push of the power button. Relays clicking, then a solid red light - so far, so good. A quick voltage check across the test point (capacitor) shows voltage within 2v of spec! We have a heartbeat!
all 4 voltage points are very close, but the service manual advises a TWO HOUR warmup before adjustment. Another quick check of the binding posts shows no significant DC offset either…:-)
Just got all the settings - voltage rails x4, bias x2, and DC offset x2 - done, and got the whole thing reassembled. Going to grab an old pair of bookshelf speakers to test it out, before moving it into my 2ch system…
Standing back with my arm outstretched, fire extinguisher on the table (I’m not kidding), I tapped the power button this morning. Standby mode activated without a problem. Next, the moment of truth…
a second push of the power button. Relays clicking, then a solid red light - so far, so good. A quick voltage check across the test point (capacitor) shows voltage within 2v of spec! We have a heartbeat!
all 4 voltage points are very close, but the service manual advises a TWO HOUR warmup before adjustment. Another quick check of the binding posts shows no significant DC offset either…:-)
Just got all the settings - voltage rails x4, bias x2, and DC offset x2 - done, and got the whole thing reassembled. Going to grab an old pair of bookshelf speakers to test it out, before moving it into my 2ch system…
daddyjt
3 ·
Re: Mark Levinson 331 amplifier repair.
Natalie Merchant...I think that is the chick's name...try streaming the, "Peppery Man".
Tom
Tom
treitz3
2 ·
Re: Mark Levinson 331 amplifier repair.
very nice! I hope I can post similar conclusions to my repair! :-D
VR3
1 ·
Re: Mark Levinson 331 amplifier repair.
Posted Monday at 06:50 PM
I hooked it up to an old AMC preamp, NHT ST4 speakers and my IPad playing some music ro make sure it wouldn’t damage my 3.3 speakers. All good, so I had my son help me relocate the Levinson to the wheeled dolly, and got it hooked up in the 2ch system (Oppo 105 to a BiilD C1 (with new black faceplate) to the Levinson to the NHT 3.3 pair).
Best news right out of the gate is that the 60hz buzz in the left channel is completely gone. In fact, the amp is DEAD silent at idle - yay! Next great news is the binding post upgrade - while I’m sure Mark Levinson purists would argue the point, the stock posts were fundamentally flawed not only because they are prone to breakage (3 of mine had previously been broken and glued), but worse, they did not accept banana plugs. Thanks @wrf for the extra set of 4 that perfectly matched what I had on hand.
The first track I listened to was Sandman by America on SACD. This track throws the widest soundstage of anything I have ever heard. While the Levinson did well, it was not quite as good as my upgraded 9t pair.
Next was Takin’ it to the Streets by the Doobies on SACD. This is where we started to realize the allure of Levinson. It excelled at bass control, and this tack has a fantastic snappy bass line that can come across a bit muddy - the Levinson was magic here.
Next was my all-around go-to, Private Investigations by Dire straits on SACD. All I can say is wow - the separation, staging, dynamics… superb. Better than the 9t pair? Different…
then I ran through some FLAC files by Erasure, Katie Melua, Klymaxx and Adele. After my limited listening, I will summarize by saying that the Levinson is exceedingly forgiving, making less than perfect recordings really shine. The Silver 9t pair are brutally honest, and less than perfect recordings can sometimes suffer at their hands. But where the Levinson really shines is its bass control. NOTHING sounded even remotely boomy or muddy - phenomenal.
I will be playing with this for many more hours. More to come…
I hooked it up to an old AMC preamp, NHT ST4 speakers and my IPad playing some music ro make sure it wouldn’t damage my 3.3 speakers. All good, so I had my son help me relocate the Levinson to the wheeled dolly, and got it hooked up in the 2ch system (Oppo 105 to a BiilD C1 (with new black faceplate) to the Levinson to the NHT 3.3 pair).
Best news right out of the gate is that the 60hz buzz in the left channel is completely gone. In fact, the amp is DEAD silent at idle - yay! Next great news is the binding post upgrade - while I’m sure Mark Levinson purists would argue the point, the stock posts were fundamentally flawed not only because they are prone to breakage (3 of mine had previously been broken and glued), but worse, they did not accept banana plugs. Thanks @wrf for the extra set of 4 that perfectly matched what I had on hand.
The first track I listened to was Sandman by America on SACD. This track throws the widest soundstage of anything I have ever heard. While the Levinson did well, it was not quite as good as my upgraded 9t pair.
Next was Takin’ it to the Streets by the Doobies on SACD. This is where we started to realize the allure of Levinson. It excelled at bass control, and this tack has a fantastic snappy bass line that can come across a bit muddy - the Levinson was magic here.
Next was my all-around go-to, Private Investigations by Dire straits on SACD. All I can say is wow - the separation, staging, dynamics… superb. Better than the 9t pair? Different…
then I ran through some FLAC files by Erasure, Katie Melua, Klymaxx and Adele. After my limited listening, I will summarize by saying that the Levinson is exceedingly forgiving, making less than perfect recordings really shine. The Silver 9t pair are brutally honest, and less than perfect recordings can sometimes suffer at their hands. But where the Levinson really shines is its bass control. NOTHING sounded even remotely boomy or muddy - phenomenal.
I will be playing with this for many more hours. More to come…
daddyjt
6 ·
Re: Mark Levinson 331 amplifier repair.
Posted February 13
Ok, that didn’t take long - I realized that the modification I outlined above would have to be completed FOUR (4) times. FOUR.
Caps are on the way.
Next topic - binding posts…
Ok, that didn’t take long - I realized that the modification I outlined above would have to be completed FOUR (4) times. FOUR.
Caps are on the way.
Next topic - binding posts…
daddyjt
1 ·
Mark Levinson 331 amplifier repair.
I started this project earlier this year, and just wrapped it up this week. I posted a step by step on another forum, and thought I’d post some of the highlights here since it had a happy ending…
Posted February 10
A little backstory on this amplifier…
I bought this used at an estate sale about 7 years ago for $900. The guy that owned it had the power supply caps and intended to replace them to correct a “known issue” with the Levinson 3xx series (more on that in a minute). The gal I bought it from (daughter) had even located the original box and packing material. This is a BEAST of an amplifier, weighing in at 120lbs - with lots of sharp edges, lol. A couple years ago, it developed a 60hz buzz in the left channel, which is a hallmark of the aforementioned “known issue” - The power supply has 4x 44,000uf 75v caps, and 4x 1,900uf 150v caps. That’s 183,000uf of power supply capacitance! Anyway, the “known issue” is the 1,900uf 150v caps. Apparently they were under-speced and virtually always fail. The solution is to bump up to 1,900uf 250v. This is a true dual-mono amp, with dual .8 kva transformers, which contributes substantially to the weight.
When the amp developed the buzz, I popped it open to replace the caps… Full stop. This thing is built like a jigsaw puzzle (see photos below). I had neither the time nor inclination to tear into it, so into the storage room it went. Fast forward to October of 2023, this amp was in the path of the flood we had at our home, where it suffered very minor water exposure (water did not even enter the internals of the amplifier). I learned about how insurance works on items such as this - they take the original value of the item and pay you half. Then, if you replace the item, they will pay anything you spend OVER the half they paid you, up to the original value. For this amplifier, they calculated original value at $8,000 - so they paid me 4k, and would have paid an additional 4k, IF I spent over 4k on a replacement. Needless to say, I have no need (or desire) for an $8,000 amplifier. My plan was to ship in to Levinson and have the caps done. Well…. Levinson refuses to work on this amplifier, as it’s “aged out” of their service agreement. Further, Levinson (Madrigal) refuses to release schematics. That leads to a service network of exactly THREE people in the country. Worse, a recap on this amplifier can be expected to run between $2,000 and $3,000 (NOT including shipping). Ouch.
Theres something liberating about having nothing to lose. I decided that since I’ve been paid out 4x what I spent, I’m going to take a stab at it, and I figured you all might want to tag along…
Posted February 10
A little backstory on this amplifier…
I bought this used at an estate sale about 7 years ago for $900. The guy that owned it had the power supply caps and intended to replace them to correct a “known issue” with the Levinson 3xx series (more on that in a minute). The gal I bought it from (daughter) had even located the original box and packing material. This is a BEAST of an amplifier, weighing in at 120lbs - with lots of sharp edges, lol. A couple years ago, it developed a 60hz buzz in the left channel, which is a hallmark of the aforementioned “known issue” - The power supply has 4x 44,000uf 75v caps, and 4x 1,900uf 150v caps. That’s 183,000uf of power supply capacitance! Anyway, the “known issue” is the 1,900uf 150v caps. Apparently they were under-speced and virtually always fail. The solution is to bump up to 1,900uf 250v. This is a true dual-mono amp, with dual .8 kva transformers, which contributes substantially to the weight.
When the amp developed the buzz, I popped it open to replace the caps… Full stop. This thing is built like a jigsaw puzzle (see photos below). I had neither the time nor inclination to tear into it, so into the storage room it went. Fast forward to October of 2023, this amp was in the path of the flood we had at our home, where it suffered very minor water exposure (water did not even enter the internals of the amplifier). I learned about how insurance works on items such as this - they take the original value of the item and pay you half. Then, if you replace the item, they will pay anything you spend OVER the half they paid you, up to the original value. For this amplifier, they calculated original value at $8,000 - so they paid me 4k, and would have paid an additional 4k, IF I spent over 4k on a replacement. Needless to say, I have no need (or desire) for an $8,000 amplifier. My plan was to ship in to Levinson and have the caps done. Well…. Levinson refuses to work on this amplifier, as it’s “aged out” of their service agreement. Further, Levinson (Madrigal) refuses to release schematics. That leads to a service network of exactly THREE people in the country. Worse, a recap on this amplifier can be expected to run between $2,000 and $3,000 (NOT including shipping). Ouch.
Theres something liberating about having nothing to lose. I decided that since I’ve been paid out 4x what I spent, I’m going to take a stab at it, and I figured you all might want to tag along…
daddyjt
3 ·
Re: Post a picture.....any picture...part deux...
Alien chest buster pad and pen set at Walmart.
SCompRacer
5 ·