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Troubleshooting SCR-2

C

Charles218

AK Subscriber
Subscriber
A few months ago I purchased a SCR-2, tonight was the first time that I tried to use it. I've got a pair of Magnapan MG-1's and AR-3A's, hooked them both up to the SCR. The SCR is connected to my C30 preamp which is driving a 2205. Button one on the SCR powers the MG-1's, but when go to button two the AR's are silent. The strange thing is if I push both buttons one and two I get sound from both the MG-1's and the AR's. Any idea what the problem might be?

Thanks!
 
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Have you tried swapping the speaker connectors to see if the problem follows the speakers?

Larry
 
Charles218 said:
A few months ago I purchased a SCR-2, tonight was the first time that I tried to use it. I've got a pair of Magnapan MG-1's and AR-3A's, hooked them both up to the SCR. The SCR is connected to my C30 preamp which is driving a 2205. Button one on the SCR powers the MG-1's, but when go to button two the AR's are silent. The strange thing is if I push both buttons one and two I get sound from both the MG-1's and the AR's. Any idea what the problem might be?

Thanks!
Click to expand...


Charles...I think you have the IC between the C30 and the MC 2205 connected at the #1 output jacks of the C30 rather than at the outputs labeled "MAIN".

Outputs #1 and #2 of the C30 are switched on/off by the front panel speaker buttons; the MAIN outs are always hot.

HTH, Eric
 
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Glad it helped.

Also Charles, the set of outs labeled "LINE" are regulated by the HEADPHONE level control on the front of the C30. That would come in handy if you every wanted to connect another amplifier enabling you to regulate volume of another pair of speakers independently of the fronts. The LINE out jacks are also affected by the main volume control which would also come in handy for bi amplification.

A lot of versatility is built into the C30.
 
I tried the AC power outlets on my SCR-2A the other day. With the relay plugged into a wall outlet, and the multi-pin plug into the back of the C28. The AC outlets on the relay did not work. Also, the relay itself does not seem to stop working whether it's plugged into a wall outlet or not. What is the purpose of the AC line on that relay? Does it only power the 2 AC outlets?

Whether plugged in to AC or not, the relay still allows me to switch between two sets of speakers from the front panel switches on the C28. It seems to be a passive relay in that regard. It's cool. But I had been powering my MC2105 from the "Amp" outlet on the back of the C28 and my service guy as well as others had advised against this as that outlet can sometimes take a surge and fuse open. So now the relay is unplugged and working, and the C28 and the MC2105 are plugged into the wall.

Eventually I want to get the Magnepan DWM and power it with my MC250. But I need to figure out how to wire it up. It would be neato to be able to use the relay and the C28 front panel switches to bring the MC250/DWM bass panel in and out as needed. Any suggestions?
 
Acc to the OM, the A/C outlets of the SCR2 are controlled by relay when the preamplifier is switched on (SCR2 plugged in, obviously).

If that is not happening, I suspect a fault lies in the SCR2.

If I understand your question, you wish to be able to switch an additional speaker(s)? on/off from the C28 speaker switches which are to be powered by a separate amplifier.

The only way that I can see would be to connect the secondary amplifier and speakers to the SCR2 - at either set of output terminals - MAIN or REMOTE depending on which switch on the C28's front panel you desire to accomplish the switching.

The MC250 has no power switch which means you'll need to find some way of powering it on/off if the outlets of the SCR2 are not working.
 
Thanks 62caddy. Maybe you are right on the fault being with the relay. When plugged into the wall, the multi-pin connector plugged into the back of the C28, and the C28 powered on; there is no power present at either outlet on the relay. It's one I bought some years ago from Audio Classics. I never had any reason to try the outlets before. I should retire it. And anyway, I'm not sure you could take the signal from the relay outputs into a second amp? Those outputs are amplifier current - no? Not line level signals?

More and more I guess I like the sound of the Maggies. That DWM would give me more bass and keep it tight. The old Pioneer C99A boxes don't seem to get enough use to justify the relay. Also, Mark Wilson tells me those push switches that select speakers, tape monitors tape assignment flows and high/low filters have not been available now for 15 years... When they go, they are gone...

Do you think I could use the second set of "Main Output" sends on the C28 to get the job done? The C28 has two sets of Main Output sends, (Left/Center/Right and Left/Center/Right). Maybe those are designed to drive two stereo amps? I never tried the second set as I never had two amps! I could maybe run one set L/R to the MC2150/MMG panels, and the second set L/R to the MC250/DWM panel, then plug the MC250 into the green "Power Amp" outlet on the C28 backside as I always had done? I could then use the Power Amp On/Off switch on top of the C28 to bring the MC250/DWM bass panel in and out as desired, or power the MC250 from a switched power bar?

I went back to the manual and I think I have a better idea of what all those service outlets on the back panel of the C28 do. "When all else fails, read the directions..." :rolleyes: The black ones are switched at the front panel Volume/Power switch. The green ones are switched by the Power Amp On/Off slider switch on the top. The red one is always on. My man Mark says avoid them because (as stated in the manual) loads greater than 600 watts can overload these outlets. Thanks twice for your never-ending willingness to share your knowledge.
 
By all means use both sets of preamplifier outs if you're running two amplifiers. Keep in mind the outputs on the C28 are always "hot" and are not switched by the front panel speaker switches unlike with the OP's C30.

Too bad about the outlets not working on the SCR2. Sounds like something wrong with the internal A/C relay in the SCR2, or possibly a problem with the C28 not tripping the relay. Since it's small & relatively easy to ship, why not send it back to Audio Classics and have them test it for you? If it's discovered to be defective, perhaps they'll give you credit towards another SCR2 since you purchased it there. It would be the ideal solution for providing A/C power to your amplifiers as I agree with the others who advise against plugging amplifiers into the C28. Source equipment is fine for the C28's outlets.
 
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