drsickstrings 3 Posted August 10, 2016 Share Posted August 10, 2016 I'm new to this forum. I had Carver equipment years ago and just got some more. I just bought a Carver C-1 and M500t. When I first hooked it up there was no sound out of the left channel. After fiddling with the connection I got sound. I pulled the covers off the preamp and sprayed the switches and pots to clean them. It works but there seems to be a lot more output out of one channel than the other. This is the preamp because I switched the cable left for right and the problem changed sides. I just wonder if maybe the balance needs to be sprayed a little more or possibly replaced. I'd appreciate any input into this. The boards are clean with no signs of leaky caps or bad traces, bad solders etc. Even if somebody has a link or a suggestion to point me in the right direction I'd appreciate it. Link to comment Share on other sites More sharing options...
pindrop 330 Posted August 10, 2016 Share Posted August 10, 2016 Welcome! You certainly jumped back in with 2 of the best pieces. Get them both upgraded after you've been here a while, unreal sound considering the cost. Hang on and one of the tech/ members will answer your questions. Pindrop 1 Link to comment Share on other sites More sharing options...
aslan7 954 Posted August 10, 2016 Share Posted August 10, 2016 Welcome Dr. Sickstrings! Can't post right now. Lightning storm!!! I'll be back. 1 Link to comment Share on other sites More sharing options...
Maddmaster 957 Posted August 10, 2016 Share Posted August 10, 2016 Good luck on the upgrade. I've been trying to get on someone's schedule but they all seem to me booked. Hopefully they will catch up and be able to take more work. Congrat's on your new acquires. 1 Link to comment Share on other sites More sharing options...
4krow 5,059 Posted August 10, 2016 Share Posted August 10, 2016 Welcome to the site, and yes, you will find just what you need in the way of advice for these issues. Thing is, there are few things that can cause the issue mentioned. Cleaning the controls is a good start, and now you can also eliminate circuitry by switching out the tone controls, sonic holography, and even the rumble filter located on the back panel. Having done this will allow you to determine the possible offending circuit. Keep us posted, and if you get a chance, there some situations that photos are helpful. 1 Link to comment Share on other sites More sharing options...
RPA-1 Man 596 Posted August 12, 2016 Share Posted August 12, 2016 drsickstrings, Are you making anymore progress? 1 Link to comment Share on other sites More sharing options...
drsickstrings 3 Posted August 12, 2016 Author Share Posted August 12, 2016 drsickstrings, Are you making anymore progress? I tried it today. Tried turning off all the effects and it sounds pretty even. The VU meters are still not equal but the sound coming out of the speakers sounds about even. I haven't had enough time to really take it out of the stand and look inside. I'd actually like to do some measurements and see if now it is still a preamp issue or the meters are just not reading correctly. Link to comment Share on other sites More sharing options...
4krow 5,059 Posted August 12, 2016 Share Posted August 12, 2016 After reading the OP again, it seems that the trouble could be about an RCA jack connection. A fix can be as simple as reconnecting the RCA cables in and out a few times, to replacing the offending RCA jack. In that case, there will be a little surgery involved. 1 Link to comment Share on other sites More sharing options...
RPA-1 Man 596 Posted August 13, 2016 Share Posted August 13, 2016 I don't know what you have for test equipment but a simple program such as the free version of truerta https://www.trueaudio.com/rta_abt1.htm is simple to use with your computer sound card and will tell you if the left/right outputs are the same even if you don't go through the calibration process. If you don't calibrate the levels of truerta it will still show you the difference between channels even if the measurements are not actual levels. 2 Link to comment Share on other sites More sharing options...
drsickstrings 3 Posted August 13, 2016 Author Share Posted August 13, 2016 After reading the OP again, it seems that the trouble could be about an RCA jack connection. A fix can be as simple as reconnecting the RCA cables in and out a few times, to replacing the offending RCA jack. In that case, there will be a little surgery involved. Thanks I'll try that. Link to comment Share on other sites More sharing options...
drsickstrings 3 Posted August 13, 2016 Author Share Posted August 13, 2016 I don't know what you have for test equipment but a simple program such as the free version of truerta https://www.trueaudio.com/rta_abt1.htm is simple to use with your computer sound card and will tell you if the left/right outputs are the same even if you don't go through the calibration process. If you don't calibrate the levels of truerta it will still show you the difference between channels even if the measurements are not actual levels. I'll look it up. Thank you. Link to comment Share on other sites More sharing options...
aslan7 954 Posted August 13, 2016 Share Posted August 13, 2016 Hey Drsickstrings, I promised I'd be back after that lightning storm. Unfortunately my computer died right after that and it's now in the shop. Anyways, we extend you a warm welcome. The tech's here are incredibly knowledgeable and it sounds like you are on the right track troubleshooting your RCA jacks. We love pics and enjoy ALL audio equipment--particularly Carver's of course. Post any that you have using the "insert image" button during post reply. Your C1 will be nursed back to health in no time. Cheers! Link to comment Share on other sites More sharing options...
drsickstrings 3 Posted August 13, 2016 Author Share Posted August 13, 2016 Hey Drsickstrings, I promised I'd be back after that lightning storm. Unfortunately my computer died right after that and it's now in the shop. Anyways, we extend you a warm welcome. The tech's here are incredibly knowledgeable and it sounds like you are on the right track troubleshooting your RCA jacks. We love pics and enjoy ALL audio equipment--particularly Carver's of course. Post any that you have using the "insert image" button during post reply. Your C1 will be nursed back to health in no time. Cheers! Hi; Thank you. Looks like buying Carver equipment WAS a good idea after all because there is a lot of support. At this point all I can say is : are there any tips you have for cleaning the RCA jacks other than spraying them and checking the solder joints? Again thanks. I appreciate all the help. Link to comment Share on other sites More sharing options...
RPA-1 Man 596 Posted August 13, 2016 Share Posted August 13, 2016 You may have tried this already but is the audio low on one side regardless of the input you choose? Link to comment Share on other sites More sharing options...
drsickstrings 3 Posted August 13, 2016 Author Share Posted August 13, 2016 You may have tried this already but is the audio low on one side regardless of the input you choose? Seems to be. Right now I am using Tape 1 for my cd player and it seems to be the closest to balanced I have found. I also think the needles on the M500t should be calibrated. Of course that will be another post. Link to comment Share on other sites More sharing options...
RPA-1 Man 596 Posted August 13, 2016 Share Posted August 13, 2016 Now that I can access the sight again, have you tried the Processor input. That is as close as you get to the volume control without actually injection a signal directly into the volume control itself. That will eliminate the input selector and Tape Monitor switches. 1 Link to comment Share on other sites More sharing options...
RPA-1 Man 596 Posted August 13, 2016 Share Posted August 13, 2016 Of course that doesn't eliminate the Balance control but at least all the input selectors up to that point will be eliminated. 1 Link to comment Share on other sites More sharing options...
RPA-1 Man 596 Posted August 13, 2016 Share Posted August 13, 2016 I would take a mono signal, like a 1KHz tone and inject that tone into both the left and right Processor Inputs and measure the output levels at Main 1 Out. You really need to verify just how much of a difference there actually is between the two channels. 1 Link to comment Share on other sites More sharing options...
drsickstrings 3 Posted August 13, 2016 Author Share Posted August 13, 2016 Now that I can access the sight again, have you tried the Processor input. That is as close as you get to the volume control without actually injection a signal directly into the volume control itself. That will eliminate the input selector and Tape Monitor switches. I haven't tried it yet but I'll give it a shot. It seems like the setup is working better the more I use it. Possibly the caps needed a good workout as well. Link to comment Share on other sites More sharing options...
kve777 6,657 Posted August 13, 2016 Share Posted August 13, 2016 Have you checked the output in a pair of headphones? Link to comment Share on other sites More sharing options...
drsickstrings 3 Posted August 13, 2016 Author Share Posted August 13, 2016 Have you checked the output in a pair of headphones? No I haven't but I'll give it a shot. Just have to hunt up a 1/4" adapter. Link to comment Share on other sites More sharing options...
drsickstrings 3 Posted September 17, 2016 Author Share Posted September 17, 2016 Welcome to the site, and yes, you will find just what you need in the way of advice for these issues. Thing is, there are few things that can cause the issue mentioned. Cleaning the controls is a good start, and now you can also eliminate circuitry by switching out the tone controls, sonic holography, and even the rumble filter located on the back panel. Having done this will allow you to determine the possible offending circuit. Keep us posted, and if you get a chance, there some situations that photos are helpful. I finally got back to the Carver....and here is what I found. Cleaned everything. The preamp looks SUPER clean inside. Standing back playing something sounded off. One channel sounded decidedly low fi but loud. I began to suspect the amp itself. I just plugged in my HK 870 amp into the Carver preamp and it sounds fantastic. I think I am going to overhaul that amp. A couple of the capacitors are suspect and may have leaked a bit but it is in good condition overall. If anybody has a M500T overall thread they would like to share I would appreciate it. Link to comment Share on other sites More sharing options...
zumbini 6,138 Posted September 17, 2016 Share Posted September 17, 2016 Howdy drsickstrings and a belated welcome to the forum. ....are there any tips you have for cleaning the RCA jacks other than spraying them and checking the solder joints? Signet makes an excellent cleaning tool for RCA jacks and sockets that can be used wet or dry. Made from molded thermoplastic embedded with a mild abrasive, they are inexpensive and last a long time. Site menber helicopterpilotdoug sells a connection cleaning kit on his website Douglas Connection. It contains the same Signet cleaning tool, plus polishing cloths and DeoxIT D and G-series wipes. 3 Link to comment Share on other sites More sharing options...
Dadvw 2,802 Posted September 17, 2016 Share Posted September 17, 2016 Welcome to the site! Here is my thread for a M500t recap....... http://thecarversite.com/yetanotherforum/default.aspx?g=posts&t=25877 Dadvw 1 Link to comment Share on other sites More sharing options...
4krow 5,059 Posted September 17, 2016 Share Posted September 17, 2016 I cant think of a better idea than cleaning the INSIDE of an RCA jack! remember, a SMALL signal passes through that connection. just imagine only a little bit of crud in there. 1-2 volts can easily be affected from passing cleanly through such a connection. same goes for volume controls, etc etc. 1 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now