Serious distortion/feedback issues

Hi all,
let me explain situation as best I can. I can't see the wood for the trees with this one and am pretty sure that I shouldn't have a feedback loop or distortion and have tried many different permutations and still have crap sound quality.

* 2xtechnics turntables and DJ mixer-signal from mixer (MASTER OUTS) goes to bigger mixing desk and turntables have their own channel, as does the Ren and my iMac
* Behringer firerwire audio interface IN and OUT from main mixing desk to carry audio from IMac
* MPC Ren-has own channel on big mixing desk, AUDIO OUTS to desk
* From DJ mixer (BOOTH) RCA jacks to MPC Ren PHONO IN.

Sound quality is terrible when I push up the REC GAIN on the MPC Ren? Sampling is near impossible. I have another way of routing signal but surely by going OUT of the DJ Mixer direct to the Ren I should have perfect signal for recording/sampling?

I have also tried going via the MASTER OUTS on the DJ mixer with same result? It isnt the DJ mixer as I also interchange and go via the RCA jacks to my MPC2000xl?

MPC Ren's audio settings in preferences is MPC Ren audio 1+2 OUTPUT (to main mixing desk) and INPUT MPC Ren (from RCA jacks from DJ mixer).

If you can follow my signal path please tell me where i am going wrong? I have also routed direct from technics turntable RCA jacks to the REN RCA jacks to no avail? With no sound either? And yes, it is switched to phono, not line.

Any suggestions as to a signal path? The hum and distortion is horrible, rendering sampling a no go....

Hum sounds like turntable not grounded to mixer properly.

I would try get it going directly into the Renaissance phono inputs, including connecting the ground wire from the turntable to the ground post on the Renaissance, no need for anything else in-between.

SimonInAustralia wrote:Hum sounds like turntable not grounded to mixer properly.

I would try get it going directly into the Renaissance phono inputs, including connecting the ground wire from the turntable to the ground post on the Renaissance, no need for anything else in-between.

Thanks for reply mate. Surely the grounding has already occured as my turntables are grounded at the dj mixer source? No issues with MPC2000xl? Also, due to my set up, couldn't ground on the Ren as the turntables aren't close and the ground wire won't stretch! ha ha

fluxsta wrote:Thanks for reply mate. Surely the grounding has already occured as it my turntables are grounded at the dj mixer source? No issues with MPC2000xl?

Yes, you are correct, if it sounds OK through the DJ mixer into the MPC2000XL, it should be grounded correctly.

What inputs have you tried from the DJ mixer to the Renaissance?

You mention that you are going into the phono inputs of the Renaissance from the DJ mixer, are you switching that input from phono to line?

Do you have cables or adapters to try connecting it to the 1/4" centre inputs of the Mic/Line Rec In combo connectors, set to line?

SimonInAustralia wrote:What inputs have you tried from the DJ mixer to the Renaissance?

You mention that you are going into the phono inputs of the Renaissance from the DJ mixer, are you switching that input from phono to line?

Do you have cables or adapters to try connecting it to the 1/4" centre inputs of the Mic/Line Rec In combo connectors, set to line?

MASTER OUT/BOOTH/FX OUT from DJ mixer, all of which work as outputs and their impedance is the same, as is dB output. Switching from phono to line makes no difference. Going from LINE OUT on the DJ mixer makes no difference. I may have cables/adaptors to check on other Ren inputs, but thats not the point really as it in theory should work via the RCA Input, and having to do a workaround misses the point of an expensive all singing. all dancing piece of equipment, particulalry when my 2000xl doesn't face these issues?

I looked at the tech specs and it doesn't actually give impedance etc for RCA input? So that might be worth a go?

Pasted from site:

Record input (L and R): XLR/ 1/4-inch Combo x 2 balanced -40dBu, input impedance 11k ohms; RCA with PHONO preamp

Just wondering as a troubleshooting exercise, to see if you can narrow down what is going on.

Don't you have the same cables/connectors required for the Renaissance Rec In 1/4" inputs, that you use to go into your MPC2000XL?

SimonInAustralia wrote:Just wondering as a troubleshooting exercise, to see if you can narrow down what is going on.

Don't you have the same cables/connectors required for the Renaissance Rec In 1/4" inputs, that you use to go into your MPC2000XL?

ha ha, that thought just hit me after i had typed previous entry! Will have to try that when I finish work......

It is just RCA to 1/4" cables!!

If still having the problems with the 1/4" Rec In inputs, maybe try disconnecting everything except the input into the Renaissance from the DJ Mixer, and monitor the output of the Renaissance through headphones, to rule out any weird grounding type issues with connections to your other gear.

SimonInAustralia wrote:If still having the problems with the 1/4" Rec In inputs.

Works like a dream through the mic 1/4". Why is the phono rca connection so sh** then? Thought it had a preamp? My signal was more than boosted via my Urei mixer....?

Anyway, sound quality better, much better. Now just need second pair of jacks to hook up the 2000xl that I stole the RCA>1/4" cable from