OK what could be wrong

cstmar01

Just got a Rotel RC-1090 off of Audiogon. My current set up I run RCA from the CDP out to CDP in on my pre with balanced XLRs from the pre to my amp.

Well never had an issue but now with the Rotel, when it is connected via balanced I get terrible popping when switching inputs and turning the unit on and off. Also when I turn the volume past about 1/8 I'm getting distortion and feedback and crackling.

RCA out does not do this, so it has to be something with the XLR. I removed the top to see if there was something out of place which there wasn't to my eyes.

Any idea of what could be wrong? There is a switch on the back that says balanced on and off which was turned the right way and same with my amp.

I haven't left feedback yet on the gon nor said anything to the seller. I wanted to see if maybe its just my dumbness first before going further.

FTGV

Maybe it has a non standard pin out on the XLR con.

cstmar01

FTGV

The standard pin out for XLR cons are pin1-ground,pin2-hot,pin3 inverted.
I would check the manuals for the pre and amp to confirm they follow the standard pin config.


btw.that is a very beefy power supply for a preamp.

cstmar01

I'm not finding anything on either that would say different that the norm.

http://www.rotel.com/content/manuals/rc1090_multi.pdf

Tour2ma

I'm guessing that the noise is both ch's and the source switching that produces it involves going to/ from the CDP... yes?

If so, the first suspect that occurs to me would be dirty contacts in the IC selector switch. If original owner used RCA's and the switch has been in that position all its life, the Balanced position contacts may have oxidized.

Might take some Caig De-Oxit, but if none is handy... turn off everything and flip the switch back and forth several times... it should be self cleaning to some extent.

If not the above, my second guess would be that the cause is Grey Goose related... :biggrin:

lakesailor

Sounds like a connection loading issue to me. Your best bet is to stick with the RCA's until you can find someone with Rotel exp. to made some adjustments for you.

quadzilla

Stupid question, but if you're running balanced out to the amp, why is the balanced out set to off? Or what it just like that when you took the pic?

cstmar01

Quad...that was just the way I took the picture. I had it the correct way when connecting.

The issue happens when switching between any source. If hooked up with RCA's you can hear a switching happening inside the pre but nothing through the speakers, in balanced the sound is audiable through the speakers. When the unit is powered on with balanced you can hear a pop in both channels, when RCA no sound.

Its strange as I've never heard this issue. It did seem better after I moved the switch around a bit in terms of the distortion when turning up the volume. I got it to about 80DB before the scratching noise started.

Do you think it would just be better to return this to the seller and state its just not working properly? He stated no issues in his ad which to me, there are issues, but he just may not have known about them

jinjuku

It's a long shot but could you make a pair of RCA to XLR's (or get an adapter) and try the XLR's in on the Pre, by-pass the RCA in's?

Run those from the CDP and then flip and do the same from the RCA pre-outs to the amp?

miner

Problem caused by too much Grey Goose consumption.

I have the same pre - Rotel tech support has always been quick to respond to any of my requests. Give them a try.

Tour2ma

cstmar01 wrote: »

It did seem better after I moved the switch around a bit in terms of the distortion when turning up the volume. I got it to about 80DB before the scratching noise started.

Ta-da... It may continue to get better with additional switching, but I'd recommend trying some DeOxit. If problem still persists, you'll likely need to replace the switch. Rotel CS should be of help in getting a replacement.

Does the problem output switch feel different, e.g., looser, than the CD input one?

Meanwhile, I'd advise the seller of the problem and the plan thus laying the groundwork for compensation.

reeltrouble1

So you decided to step it down some?

Well you'll appreciate the next one even more.

RT1

cstmar01

Tour2ma wrote: »

Ta-da... It may continue to get better with additional switching, but I'd recommend trying some DeOxit. If problem still persists, you'll likely need to replace the switch. Rotel CS should be of help in getting a replacement.

Does the problem output switch feel different, e.g., looser, than the CD input one?

Meanwhile, I'd advise the seller of the problem and the plan thus laying the groundwork for compensation.

I advised the seller and might just try and return it. I'm getting an adcom GFP-750 to match my amp anyways so this isn't really needed right now. I just didn't know about the adcom until after I purchased this rotel so yeah. :frown:

I've called and emailed rotel but haven't heard anything back from them yet. We'll see I guess.

Also haven't heard back from the seller. He did state he never used the Balanced connections only unbalanced. I told him I would even pay for the shipping back to him if it comes down to just returning but no word from him yet.

heiney9

Just return it, the 750 is a better pre-amp, both build and sound. Those switches are 'cheesy' in my mind.

H9

leroyjr1

Chris,


When you get the 750 let me know which one sounds better, I'm curious.

heiney9

leroyjr1 wrote: »

Chris,


When you get the 750 let me know which one sounds better, I'm curious.

How can he do that if the Rotel isn't working like it's supposed to? I'm guessing the switches need to be cleaned, if possible.

H9

leroyjr1

heiney9 wrote: »

How can he do that if the Rotel isn't working like it's supposed to? I'm guessing the switches need to be cleaned, if possible.

H9

Unbalanced works just fine.

heiney9

leroyjr1 wrote: »

The RCA side works just fine.

True.................if it is broken I'd get it back to the seller ASAP, unless he's uncooperative. The longer you have it in your posession the harder it will be to get your $$ back, unless you don't care.

H9

FTGV

heiney9 wrote: »

Just return it, the 750 is a better pre-amp, both build and sound .
H9

Speculation or have you compared them?

Tour2ma

I'll put my money on "Speculation"... same as the comment on the switches...

OP (Chris),
Since you've apparently decided to return the Rotel I hope all goes well, but if it doesn't the Caig/ replace option remains in place.

dkg999

Not sure why people disparage Rotel gear. I have listened to many Rotel components as a good friend back in IA pretty much sticks with their gear. Depending on the rest of the system that Rotel pre could easily be as good or better than the Adcom 750 pre. I can't remember if it was the 1090 or 1092 pre that I heard recently in a system and sounded outstanding. Hopefully it's just the balanced switch that needs a little cleaning and you can give them a good comparison. Synergy in your system is just like karma, fantastic when it all comes together!

cstmar01

SO

I went and wiggled the switches back and forth several times and it hasn't improved at all.

Also I changed it up and ran XLR from the CDP to pre and then XLR to amp, same thing, then just XLR CDP to pre and RCA out, same thing.

Only time it works correctly is RCA in RCA out. Also I noticed one of the feet seems to have gotten shoved into the bottom of the pre which makes it sit odd, so this is also an issue for me.

Blah still haven't heard from the seller but I paid via paypal using a CC and can file a claim which I will be doing shortly if I get no response from him.

reeltrouble1

paypal sucks. you will have to go straight to the CC company. make sure you keep your correspondence. tell the seller the item does not work and you are returning it to him and want your funds back. keep copies of everything....oh, I forgot you know this stuff....ok well paypal still sucks.

RT1

W WALDECKER

dkg999 wrote: »

Not sure why people disparage Rotel gear. I have listened to many Rotel components as a good friend back in IA pretty much sticks with their gear. Depending on the rest of the system that Rotel pre could easily be as good or better than the Adcom 750 pre. I can't remember if it was the 1090 or 1092 pre that I heard recently in a system and sounded outstanding. Hopefully it's just the balanced switch that needs a little cleaning and you can give them a good comparison. Synergy in your system is just like karma, fantastic when it all comes together!

i used to own a Rotel RC1090 with a black faceplate and it was very nice SS preamplifier and on the other hand i was cursed with a Rotel RB1080 that was a crackling ,spitting, fuse eating piece of dead weight that made my speakers sound like they had a wet moving blanket draped over them.

Tour2ma

reeltrouble1 wrote: »

paypal sucks. you will have to go straight to the CC company.

Once upon a time CC co's wouldn't accept claims where PayPal was the recipient of the fundage. Has that changed?

ALL212

How many people here believe that the switched marked "Balanced On Off" actually has any audio signal going through it? Go ahead, raise your hands.

How many people here believe that that same switch is attached to "other" hardware that does the actual signal switching? Hmmm....not many!

If the switch works at all - it doesn't need to be cleaned. That switch is controlling something else that does the actual signal change. Cheesy or not - that switch isn't your problem.

Take a look at the picture of the rear of the unit - there's entire circuit boards dedicated to the Balanced CD and Balanced connections. Since the switch is attached directly to that board it can't control the signal path at all - at least not directly. Odds are you've got a problem with one of those boards, not with the switch.

Edit...

Well never had an issue but now with the Rotel, when it is connected via balanced I get terrible popping when switching inputs and turning the unit on and off. Also when I turn the volume past about 1/8 I'm getting distortion and feedback and crackling.

Bad Op-amp will do this as will bad caps - that board has both...

FTGV

I don't have the schematic but I suspect the opamps at the input are configured as summers to sum the two halves of the differential signal thus feeding the gain stage with a single ended signal.The opamp(likely a dual) at the output would function as an invertor which derives the inverted half of the output signal to convert it back to differential.My guess is that the switches function would be to short the inverted side of the signal to ground (when the balanced in/outs are not used.)to reduce the likelihood of noise.

leroyjr1

Any word from the seller?

heiney9

Some very good advice in posts 27 & 28. Still unless you got a steal or really are enamoured with it, I'd send it back for a refund since it doesn't work.

H9

reeltrouble1

the real problem is no toobs........and that can't be fixed.

RT1