1/4" to XLR connections for board/Phase 90/amp.

[Vlady]

I am technically challenged...need to figure the best way to connect from my KORG SV2----Phase 90---Peavey keyboard amps.
I have 2 amps and 2 Phase 90's ( was going to do one left and one right as I heard Donald Fagen did this???)
Phase 90 has 1/4" in/out jacks.
When plugged directly into 1/4" of amp I got weird distortion. Told to purchase -20dB attenuators which I did. However they are XLR jacks.
Do I simply buy an XLR--1/4" adaptor cable?
Will it matter if running this combination as balanced or unbalanced?

 

[delaware dave]

Use the XLR outputs on the SV2 rather than the 1/4" outputs. Take the XLR outs of the SV2, into the attenuator's XLR in, then take the XLR out of the attenuator into an XLR to 1/4" adapter. Take the 1/4" out of this adapter to the Phase 90, then the phase 90 into the Peavey. You might have to experiment to determine whether the Phase 90 needs to go before the attenuator or whether it needs to go after the phase 90 (to reduce the signal AFTER having the signal altered by the Phase 90). My guess is that the signal coming into the Phase 90 may be too strong and is causing the distortion. Not sure, you'll have to experiment with the positioning of the attenuator, try it both ways and see which one is better. Here is the adapter that you need:

XLR to 1/4" TS adapter

If the attenuator needs to be before the phase 90 then the flow is: SV2 XLR's -> attenuator -> XLR to 1/4" adapter -> phase 90 -> keyboard amp

If the attenuator needs to go after the Phase 90 then the flow is: SV2 1/4" outputs -> phase 90 -> 1/4" to XLR adapter -> attenuator -> another XLR to 1/4" adapter --> keyboard amp. In this scenario you will need two XLR adapters rather than one.

One other thought: the XLR outputs on the keyboard should reduce the signal (they should be mic level equivalent) as opposed to the 1/4" outputs on the keyboard which are line level. Typically line level vs. mic level is about 14dB difference (+4 vs. -10dB). Coming of the SV2's XLR's might reduce the signal enough to remove the distortion. If this actually is the case then the flow 'could' be:

SV2 XLR out -> XLR to 1/4" adapter -> Phase 90 -> keyboard amp. So it is possible that by starting your connection on the keyboard with the XLR which should be a reduced output stage you might clean up that distortion without the need for the attenuator. You will still need to purchase the above adapter mentioned to convert your output from XLR to 1/4" for the phase 90. Again, you'll have to
experiment.

Final thought: purchase a small mixer. The flow would then be this: SV2 1/4" out -> Phase 90 -> small mixer -> keyboard amp. Use the small mixer to act as the attenuator.

small mixer

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[Vlady]

Use the XLR outputs on the SV2 rather than the 1/4" outputs. Take the XLR outs of the SV2, into the attenuator's XLR in, then take the XLR out of the attenuator into an XLR to 1/4" adapter. Take the 1/4" out of this adapter to the Phase 90, then the phase 90 into the Peavey. You might have to experiment to determine whether the Phase 90 needs to go before the attenuator or whether it needs to go after the phase 90 (to reduce the signal AFTER having the signal altered by the Phase 90). My guess is that the signal coming into the Phase 90 may be too strong and is causing the distortion. Not sure, you'll have to experiment with the positioning of the attenuator, try it both ways and see which one is better. Here is the adapter that you need:

XLR to 1/4" TS adapter

If the attenuator needs to be before the phase 90 then the flow is: SV2 XLR's -> attenuator -> XLR to 1/4" adapter -> phase 90 -> keyboard amp

If the attenuator needs to go after the Phase 90 then the flow is: SV2 1/4" outputs -> phase 90 -> 1/4" to XLR adapter -> attenuator -> another XLR to 1/4" adapter --> keyboard amp. In this scenario you will need two XLR adapters rather than one.

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Dave, thank-you so much...that is very well described so that even I can understand it. Very helpful!!

 

[Vlady]

Thanks again Dave...I'll do some experimenting this weekend and try your suggestions.