Patching up a Yamaha P95

  • Thread starter Thread starter Richard Monroe
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Richard Monroe

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OK- from this keyboard thing I know *nothing*! I bought a P95 for my wife for her birthday, 'cause it fits in the Neon a lot better than the Wurlitzer console, and she gets an organ also. It was the cheapest 88 key digital piano I could find that didn't feel and sound like a toy.
Of course it has midi in/out, but the only *analog* outs are a pair of 1/8"/3.5mm headphone jacks. If I plug one of those into the 1/4" line in on a small PA, I'm guessing it will work, but impedence matching is likely to be be less than perfect. Any tips here? I'm thinking a line level shifter might be useful. Of course I'll do it when the wife isn't around, but I'm just looking for the voice of experience here. (Yeah, you always use a high to low impedence transformer, etc.)-Richie
 
It should be close to line level so just try a line level input on you mixer.
 
You will want to split the 1/8 inch stereo jacks to two 1/4 inch phone cables using a Y splitter. Radio Shack has them. You may have to jury rig up 3 or more cables/adaptors to get exactly what you need.


Once you do this be sure and set the panning on your mixer all the way to the left for the cable that is the left, and all the way right for the cable that is right.

Not splitting the stereo signal into panned right/left will cause phase issues that will make the sound ugly.

Racherik
 
You will want to split the 1/8 inch stereo jacks to two 1/4 inch phone cables using a Y splitter. Radio Shack has them. You may have to jury rig up 3 or more cables/adaptors to get exactly what you need.


Once you do this be sure and set the panning on your mixer all the way to the left for the cable that is the left, and all the way right for the cable that is right.

Not splitting the stereo signal into panned right/left will cause phase issues that will make the sound ugly.

Racherik

That doesn't make sense. The "stereo" out is an incorrect nomenclature, in this case. If there really was a stereo output, what you say might be true, but- what comes out of the left side of that headphone jack, and the right side are *identical. The keys on the piano aren't panned. It's 2 channel mono, nothing stereo about it. The only issues I see are gain staging, and I/O and impedance matching. And I don't think a trip to Radio Shack will be in order, as I've already got a couple grand sunk into cables and adaptors. This is simple. Try going from a 3.5mm male miniplug into 2 female XLR's! What running a splitter should do is double the signal, as it takes the signal from both sides of the micro-headphone amp in the thing. Of course, this doubles the noise also, so as long as I have enough clean gain at the PA, it should make no difference. Given that it is a headphone out, it's probably pretty close to -10dBV line level, which makes me think the best input would be the "tape in" RCA jacks, which are looking for the output from a Walkman, IPOD, or whatever-Richie
 
That doesn't make sense. The "stereo" out is an incorrect nomenclature, in this case. If there really was a stereo output, what you say might be true, but- what comes out of the left side of that headphone jack, and the right side are *identical. The keys on the piano aren't panned. It's 2 channel mono, nothing stereo about it. The only issues I see are gain staging, and I/O and impedance matching. And I don't think a trip to Radio Shack will be in order, as I've already got a couple grand sunk into cables and adaptors. This is simple. Try going from a 3.5mm male miniplug into 2 female XLR's! What running a splitter should do is double the signal, as it takes the signal from both sides of the micro-headphone amp in the thing. Of course, this doubles the noise also, so as long as I have enough clean gain at the PA, it should make no difference. Given that it is a headphone out, it's probably pretty close to -10dBV line level, which makes me think the best input would be the "tape in" RCA jacks, which are looking for the output from a Walkman, IPOD, or whatever-Richie

Ok, let me try to explain again. I believe what you are telling me you have 2 head phone jacks? These are put there so a teacher and student can both play silently. Try plugging in a set of headphone and have a listen. What you hear should be stereo. Play on the left side of the piano and it should pan different than playing on the right side.

Now the headphone jack is a tip/ring/sleeve jack. This is how it get stereo down the cable, you got a wire for left, right, and ground. Mono is just tip and ring. Now this is where I might have been confused, most mixers have instrument & xlr mic input on their channel strips. Some mixers even have channels that combine both R&L onto a single strip. If yours does use a single strip.

Your right about impedance miss match, you want to use the instrument jacks and not the mic XLRs. The instrument jacks are high impedance. If you really really want to use your XLR cables or if all your mixer has is XLR then you ought use a direct box.

So this is why I suggested a 1/8 inch stereo to dual 1/4 inch mono Y cable, hook up and then full pan the PA/mixer left & right . You don't want to sum both the Right and Left signals directly upon each other. This is where you get phase cancellation.

When Live gigging it is most common to use just hook up Left channel to the PA and use this mono signal panned into the center. This is because rarely do venues have everyone seated in the center. For example A hard panned Left piano and hard right guitar would likely have a horrible stereo image for anyone seated at the sides of the stage.

As far as I know every Yamaha keyboard in the last 20 years or more has had stereo. All the ones I've owned in the last 15 years certainly were.

I hope this helps.

Racherik
 
Ok, got it. If what you say is true, and the headphone outputs really are panned, then what you say about using a splitter makes sense. I'll check that out. My point about the I/O remains true, though. The "tape in" jacks on the PA are -10dBV (consumer line level). The 1/4" line ins on the PA are +4dBu (professional line level). They're both called "line level", but not all line levels were created equal. Characteristically, a headphone output, although not exactly either one, is closer to -10 than +4. Also, the tape in is intended for stereo input, and will send the two inputs to the left and right main outputs, maintaining the keyboard's stereo separation. If I go to the 1/4" line ins, they will be mixed to mono and sent to both main outs, panned dead center. I understand the line levels just fine, but my keyboard knowledge is pretty weak. Thanks, I'll check it out and see if it really is panning the keyboard's input.-Richie
 
Ok, got it. If what you say is true, and the headphone outputs really are panned, then what you say about using a splitter makes sense. I'll check that out. My point about the I/O remains true, though. The "tape in" jacks on the PA are -10dBV (consumer line level). The 1/4" line ins on the PA are +4dBu (professional line level). They're both called "line level", but not all line levels were created equal. Characteristically, a headphone output, although not exactly either one, is closer to -10 than +4. Also, the tape in is intended for stereo input, and will send the two inputs to the left and right main outputs, maintaining the keyboard's stereo separation. If I go to the 1/4" line ins, they will be mixed to mono and sent to both main outs, panned dead center. I understand the line levels just fine, but my keyboard knowledge is pretty weak. Thanks, I'll check it out and see if it really is panning the keyboard's input.-Richie

The point of having a mixer is so you can mix. So don't use the tape in/outs. Besides many tape in/outs are setup to only to do one or the other, you can't have both turned on at the same time. So if you want to use a cassette tape deck to record (or even a $35 Behringer uca222) you might have trouble.

My last Yamaha I use the Y splitter cable because it didn't have dedicated left/right like my current Motif ES7 does. That keyboard used a 1/4 inch headphone jack, but the new tread is to make headphone jacks 1/8 inch. You might find a single cable solution to what your looking for at a big music store. My local radio shack has only pieces to make what I needed which drove the cost up.

The parts I used were:

1) male 1/8 to 1/4 female stereo adapter ( see if you can find a 90 degree elbowed one )
2) male 1/4 inch stereo split to Y female mono
3) two 20 foot 1/4 guitar cables

Once hooked up I'd plug these into channels 3 & 4 on my mixer with 3 panned hard left and 4 panned hard right. When live gigging I just use the left channel panned center because of the reasons stated above.

Don't worry the volume control on your piano will let you adjust the signal strength to mixer just fine. The instrument inputs on your mixer are high impedance so you'll be good to go. Just make sure you set all the gains properly.

One bonus thing with your piano model, is with the two headphone ports on the front of the piano you can use the left side of a set of isolation ear buds if you live gig with electric guitar players who won't play quiet. So you can self monitor.

This might sound drastic but if it was my keyboard I'd open it up and solider a custom modification and have 1/4 inch left and right inputs installed to the rear, side or under the keyboard.

Racherik
 
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Actually, I don't use a mixer at all, and my (small) PA has separate tape ins and tape outs. The tape ins are so you can play a CD or MP3 player through the PA, and they are configured for stereo input. My wife will be using the PA with the keyboard for solo accompaniment of a choir, so no mixing or recording of any kind will be required. If I use it in the studio, it'll just go to Midi in Pro Tools or to the variable impedence input of an Avalon AD2022, so impedance matching won't be a problem.-Richie
 
Why has nobody asked Richard exactly what model of PA/mixer he is using? If it's one of those all-in-one "heads" it may very well be mono only and all this talk is moot. Of course, why manufacturers insist on putting "Stereo" pairs of RCA jacks - marked L & R no less - on a mono mixer/amp is beyond ridiculous. Many of those all-in-one units have 2 amps which can be split with one amp doing mains in mono and the other doing monitors in mono. These can sometimes be set up for stereo operation but the user would have to know that, and know how to do it.

So, richard - exactly what model mixer or PA are you using?
 
OK- I'm using a Yamaha PD250 portable PA. The RCA tape ins are hard-wired panned hard left and right. I can't change that. Whatever goes into the left side of the tape in is going to come out of the left side speaker array, and vice versa. That should be no problem, If the headphone outs on the keyboard are panned, then the stereo inputs on the PA will maintain that panning. If it's a 2-channel mono out, then the tape ins will duplicate that input- still 2-channel mono. No problem either way. Let me state again- the panning, or lack therof, is *not an issue*. The *only* issue is impedence matching. There are essentially 4 options:

1. The headphone jack output of the keyboard goes straight to the RCA stereo tape ins on the PA.

2. The headphone jack output of the keyboard goes straight to the 1/4" line ins on 2 channels of the PA, panned hard left and right.

3. The headphone jack output of the keyboard goes to a line level shifter, changing the -10 line out to +4 line level, and then to the 1/4" +4 line ins on the 2 channels of the PA,panned hard left and right.

4. The headphone jack output of the keyboard goes to a DI box, and then from the XLR outs of the DI box to the XLR ins of 2 channels of the PA.

Those are the only options I know of, and panning and phasing is not the issue. Either way. the 2 channel input on the PA will be panned hard left and right, by hard-wire if I use the tape inputs, or by manually panning hard left and right if I use 2 PA channels. The PA will send the left and right signal to left and right without any change. The only issue is which of the 4 above patching solutions will result in the hottest, cleanest signal with the lowest noise floor. Got it?-Richie
 
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