View Full Version : NAD 3140
I just picked up a NAD 3140 integrated amp for my wifes new salon.
It will drive a pair of Mission 762i book shelf speakers 92db. sensitivity.
For awhile I will use a Music Hall 25.2 CDP as the source later I will load a music server with loss-less files and run them through a stand alone DAC.
Has anyone used this little amp? http://nadelectronics.com/products/hifi-amplifiers/3140-Stereo-Integrated-Amplifier#heading-downloads
What should i expect from it?
I'm so boring, aren't I???
Yeah, I remember it. Not as "clean" as a 3020, but far more powerful and it came into its own with the matching power amp in bi-amped form. I bet there's all sorts of tweaks and mods you could do to it now, as much for preventative repairs as much as anything else :)
I gave the old NAD a good run today,it sounds pretty good and will work well for my wifes new salon.
Nice amp. It was contemporary with the famous 3020 and often pitted against the A&R A60 and the remnants of the better Japanese amplifier ranges of the time - usually Sansui.
Agree with Dave, check it over and perhaps clean the pots and switch, and check for any leaky or bulging electrolytic caps.
If it's run in a "shop" kind of environment (I don't mean to demean a salon [hair?]), then it will be on for many hours per day, albeit at low volume levels. I'm sure tha amp will "love" this kind of gentle but prolonged use, but get it checked over first - please?????
I checked the caps for signs of failure,I'll spray the pots with Deoxit but getting it open is priority one. Later I will send it for a complete recap and over hall.
Well I opened it up today to find things I could not see just looking through the vent holes in the case. I'm glad I only let the amp run for 10 min. or so.
Seems this amp has burned up in the past and the 4 main power supply caps have bulged and one is leaking pretty bad.
1st picture is 4 bulged and one leaking power supply caps.2nd and 3rd picture shows some scorched capacitors and some replaced resistors 4th shows the top cover burned and cleaned up then re touched with black paint after a major melt down.
I contacted the seller,if he really owned this amp for 20 years he would have known about the melt down and should have disclosed it.
He said it was out of service and stored for 10 years. Guess I know why now.
I'm glad I only let it run for about 3 songs. Truth is it sounded pretty good,can you believe it?
I'm not sure if it's worth recapping due to the blackend main board.
What do you guys think? am I screwed?
Hey,I just hit 1,500 posts!
The last picture is celebrating my number of posts.
Dingdong
23-10-2011, 07:38
Can you return it and get your money back?
If not then you might be ok, depending on the quality of the repair. If the board is burnt and some tracks damaged then I'd be tempted to dump it.
If it's mostly smoke damage and the pcb is in a decent state then replacing the caps, and maybe the other reg and rectifier, and you should be okay.
Would you, once it's repaired, be happy to leave the room with it still powered up?
Can you return it and get your money back?
If not then you might be ok, depending on the quality of the repair. If the board is burnt and some tracks damaged then I'd be tempted to dump it.
If it's mostly smoke damage and the pcb is in a decent state then replacing the caps, and maybe the other reg and rectifier, and you should be okay.
Would you, once it's repaired, be happy to leave the room with it still powered up?
It will be in a fourteen million dollar building.
but it will never be left on unattended.
And yes the traces still look good.
NAD's of this generation weren't pretty inside, even when new.....
I'd get it re-capped (the big ones at least) and place it on a granite/stone chopping board with some good ventilation above. Since it's not for HiFi use, I'd also put some inline 1A or so fuses in series with the +ve speaker lines to protect them should a disaster happen (can occur with any new amp as well...). Once fettled, you may have years more out of it :)
If there is a service manual available, I'd also recap this and then check that internal setting are within the right area - or can be adjusted to be.
If no service manual can be found I'd be inclined to give up, since amps of this age will have drifted internally (dc conditions, offset, bias mainly).
Seller honestly seems surprised,at it's internal condition.
We are resolving things between us as we speak.
StanleyB
23-10-2011, 19:55
If the amp has not been used for that many years, the reservoir caps are likely to have dried up. You would have to slowly crank the mains up on the amp with a variac and leave the amp like that without playing any music through it for a day or two. The electrolytic inside the caps will then become a liquid again from its solidified state.
If you just power up an amp that has not been used for that long and pump music through it the likelihood of the caps swelling up and even leaking is an almost dead cert.
Well, it's all good.
The seller has agreed to a partial refund and I am sending the amp in for a cleaning recap and tune up.
Dingdong
23-10-2011, 21:19
Seems like a decent result then. Hope it comes back in fine fettle.
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