NAD 2200 help

[CMej6]

3 days ago I was listening to my Nad 2200 in stereo @ 8 ohms, when out of no where the left channel stops working:scratch2: Where do I begin?? There are no techs that I know of and trust around me. NW suburbs of Chicago. So I am trying to find some info, any would be great. Thank you to all.

 

[ryuuoh]

Power amp, right? Power it all down, and swap the rca cables right to left, left to right and see if the problem moves to the other channel.

 

[dr*audio]

The speaker relays in this amp go bad. As I recall, there are 2 of them. Try tapping on the relays and see if the channel comes back in. If so, replace both relays. NAD had them in stock a few years back.

 

[DavidGoncalv]

from a similar thread...

Had the exact same problem. This is probably the contacts on the output relay - they are not making good contact. Unfortunately, the relay is not built in a way to make the contacts accessible for cleaning. I tried.

Buy this relay from Mouser Electronics, they currently sell for 3.42 each:

653-G2R-24-DC24

Get at least two. If you have the preamp that goes with that amp (say, a NAD 1600), get three.

You will quickly find that the solder side of the board where the relays are located is covered by the transformer mount. Disassemble the amp chassis such that the board and transformer are loose. Don't bother trying to unmount the transformer - you'll do more damage to the screw heads than you expected and you STILL may not even be able to get it free. I found that the rail that forms that side of the chassis can be completely unbolted, which will free up the transformer enough.

Unsolder the two relays with good solder wick (add that to your Mouser order), check them against the new ones, snip the leads on the new ones where the old ones don't have them. Use a little tape to hold the relays down temporarily, solder in relays, reassemble, check and enjoy.

This is the most common issue. Be sure to set your switches on the rear to the correct settings; there is an impedance switch, bridging switch and input selecting switch - none will cause damage under normal conditions but will degrade performance when set incorrectly.

BUT - if you are not handy, may I suggest taking it to a good shop and letting them know about this issue and the fix?

Why are you snipping leads? The original relay was a double-pole single-throw (DPST); the replacement is a double-pole double-throw (DPDT), and the PC board is only drilled for the DPST relay; the new one won't drop in without clipping the two leads of the unused pair of contacts. Also, that third relay is for the 'switched-output' socket on the preamp - NAD used the same relay.

------------------------

Hope that helped; the NAD 2XXX series (at least up to 2400) used the same relays. The notes about having to loosen the chassis likely only applies to the 2100 amplifer. I found the 2400 more than open enough to access the relay solder joints.

 

[dr*audio]

I seem to remember having to pull the board out to replace the relays...

 

[CMej6]

from a similar thread...

Had the exact same problem. This is probably the contacts on the output relay - they are not making good contact. Unfortunately, the relay is not built in a way to make the contacts accessible for cleaning. I tried.

Buy this relay from Mouser Electronics, they currently sell for 3.42 each:

653-G2R-24-DC24

Get at least two. If you have the preamp that goes with that amp (say, a NAD 1600), get three.

You will quickly find that the solder side of the board where the relays are located is covered by the transformer mount. Disassemble the amp chassis such that the board and transformer are loose. Don't bother trying to unmount the transformer - you'll do more damage to the screw heads than you expected and you STILL may not even be able to get it free. I found that the rail that forms that side of the chassis can be completely unbolted, which will free up the transformer enough.

Unsolder the two relays with good solder wick (add that to your Mouser order), check them against the new ones, snip the leads on the new ones where the old ones don't have them. Use a little tape to hold the relays down temporarily, solder in relays, reassemble, check and enjoy.

This is the most common issue. Be sure to set your switches on the rear to the correct settings; there is an impedance switch, bridging switch and input selecting switch - none will cause damage under normal conditions but will degrade performance when set incorrectly.

BUT - if you are not handy, may I suggest taking it to a good shop and letting them know about this issue and the fix?

Why are you snipping leads? The original relay was a double-pole single-throw (DPST); the replacement is a double-pole double-throw (DPDT), and the PC board is only drilled for the DPST relay; the new one won't drop in without clipping the two leads of the unused pair of contacts. Also, that third relay is for the 'switched-output' socket on the preamp - NAD used the same relay.

------------------------

Hope that helped; the NAD 2XXX series (at least up to 2400) used the same relays. The notes about having to loosen the chassis likely only applies to the 2100 amplifer. I found the 2400 more than open enough to access the relay solder joints.

WOW!!! This is great info. I will order those within the next day. Hopefully I can perform the task.. Thank you so much guys.

 

[tubed]

I have the same issue with my 2200 where the right channel will sometimes not be heard upon power-up. However in this case a quick jiggle of the volume control brings the channel back into play. Dirt?

 

[DavidGoncalv]

Another common manifestation of the relay issue - when you jiggle the volume up, you are 'arcing' through the crap on the relay contacts.

 

[CMej6]

Thank you all for the fast and informative responses. Ordered new relays and I am now opening the amp up to peek around. Could use a good cleaning while im here.

 

[CMej6]

Ok. Next Q. If the right side of my amp isnt getting warm and no sound but the left is working fine, does this still sound like relays?

 

[DavidGoncalv]

Ok. Next Q. If the right side of my amp isnt getting warm and no sound but the left is working fine, does this still sound like relays?

Did you already replace the relays? If not, ask the question again after you do...

OK, OK...

First make sure you don't have something misconfigured. The rear panel switches should be set to the input you are using (LAB or NORMAL), the impedance switch to your speaker impedance, soft clipping OFF, bridging OFF. Also check your speakers. I'm assuming that the protection LED isn't on.

Second most common issue with NAD 2XXX amps (or anything NAD, for that matter) is bad solder joints. With a plastic tool, you can lightly press some parts on the PCB and see if the sound cuts in when you do that. I had the same issue on the NAD 2400.

Third, you can check if there is bias current passing through the channel's output transistors by clipping a good DMM (able to measure millivolts) on the emitter resistors. They are the bizarre white things with three leads peeking from the top.
. . . . . . . . . . . .
[a ] [ b] [c ] [ d ]

Clip the leads on the pair ab, and cd. You should see something between 10-20mV. The actual value is in the service manual.

 

[CMej6]

Yes the relays came this morning and we installed them as guided. still no luck. I will check with my DMM in a minute here. ty

 

[CMej6]

Ok. I do not have mv. Is there another setting I can use?

 

[DavidGoncalv]

Hopefully your DC Volt setting is good enough. What is the model of your meter. Set it to DC Volts and let us know what you measure.

Edit: Set to CD volts, touch the meter leads together. It should be zero. If it reads something like 0.01, this meter won't help you.
If it's an analog meter, you'd be looking for a little uptick on the needle.

Again, check the solder joints, this is a VERY common issue to NAD equipment.

 

[dr*audio]

If your meter has no mV range, it may not work for setting the idle current. It may be that you meter is auto - ranging, in which case, it won't say mV, just V, Ohms, Amps and AC / DC. If that is the case, it's ok to use. If not, go to Harbor Freight and buy a Centech DMM for $5.99. They are pretty decent, especially for the price.

 

[CMej6]

New meter reads 21.1 mv on the left and 5.0mv on the right...

 

[dr*audio]

You should be reading 7.5mV at TP201 and TP202. Looks like the warm channel is high and the cool one is a bit low. It is odd that you get no sound at all on one channel. Most likely this is not caused by a faulty component in the amp (other than the relay, which you have replaced.) If there was a bad component you would get distortion, not silence. Try cleaning the Bridging switch. If that were dirty you would lose a channel. I have the service manual on PDF if you need it. PM me with your e-mail address.

 

[DavidGoncalv]

This really sounds like a soldering issue. If your friend has a good soldering iron, start inspecting every solder joint and 'touching up' the poor looking ones.

 

[rpeck]

Buy this relay from Mouser Electronics, they currently sell for 3.42 each:

653-G2R-24-DC24



Why are you snipping leads? The original relay was a double-pole single-throw (DPST); the replacement is a double-pole double-throw (DPDT), and the PC board is only drilled for the DPST relay; the new one won't drop in without clipping the two leads of the unused pair of contacts. Also, that third relay is for the 'switched-output' socket on the preamp - NAD used the same relay.
.

Sorry to rekindle an old thread, but I am dealing with this issue on one of my AMP's ... is there any reason to not get the DPST switch?

Mouser Part #: 653-G2R-2A-DC24
Manufacturer Part #: G2R-2A-DC24

http://www.mouser.com/ProductDetail...GAEpiMZZMtSzCF3XBhmWz1dWWR22LTv3UP9bVW%2b41U=

Thank You.

 

[Bostown]

Sorry to rekindle an old thread, but I am dealing with this issue on one of my AMP's ... is there any reason to not get the DPST switch?

Mouser Part #: 653-G2R-2A-DC24
Manufacturer Part #: G2R-2A-DC24

http://www.mouser.com/ProductDetail...GAEpiMZZMtSzCF3XBhmWz1dWWR22LTv3UP9bVW%2b41U=

Thank You.

Actually this is perfect time to revive this topic, since I will be needing to perform the same surgery on the 3 NAD 2200PE units I have. They all sound fine at normal listening levels, however they can sound scratchy and have intermittent audio issues at low volume evels.

The following is some information that a shop a shop called "IN HOME STEREO REPAIR" in NY state has on their website in relation to repairing the
NAD 2200 and it's variants: - I am NOT affiliated with the shop, just wanted to point out the source of the info.

"2200, 2600, 2700 THX:
Basically the same unit, these share a common problem of intermittent audio. Especially noticed at low volume, [sound]"punches through" as volume is increased. Caused by burnt relay contacts. We upgrade the relays, upgrade the input caps, buffer IC's and modify the power circuit to give a smoother sound with better bass dynamics."

All "PE" Series products:
This line was designed with a variable power supply, with the idea of conserving energy. (The British have an bug about this, left over from WWII rationing) At your option we can eliminate this feature and increase sound quality and bass extension. This can be done at no additional charge with a repair, please inquire.
---

Does anyone know if these other fixes are required with the relay replacement or are they just recommended? also what's the modification to the power circuit (eliminating the variable power function) that they are talking about? Has anyone had their 2200 serviced there that can share a bit more about the repair/mods they've had done? (updated IEC AC socket? Updated binding post and/or input-output jacks? or similar - any photos to share?)

It seems that Universally the 2200(PE) is regarded as a solid and powerful unit with a few flaws that requires service on all of the units as a result of relays, solder joints and age. - Those things aside it's a mild mannered looking amp that can deliver some beast like performance for relatively short money + the cost of some common refurbishment.