Okay I have the *DEFINITIVE* word on this from Roland UK tech support.

*All* JV and *all* XPs have the same problem.
Its "because there's no gate on the sample" - whatever that means.
It is a design feature
And it is nothing to do with any A/D converters
There is absolutely no solution to this.

Oh dear.

The only good thing is that any expansion cards for the XP-60
etc can be used on any of the XV range of modules.
And NO they do not have this problem.
When asked "why not" he sounded unsure about this,
but said it was because there was "more memory" in the XVs..


Oh dear.
Well, I'm *really* unsure what to do at this point. I have just bought an XP-60.
I could try and send
the XP-60 back but I want to be able to lay down basic sequences
of music without a computer. And I need high quality classical
/acoustic music instrument sounds. And I dont think anything else
will be within my budget (c.GBP 1100)

Alec

OK, flame me but I think this is all a fuss over nothing.

How big a problem is this distortion - really? Is it really and truly noticeable to anyone other than those tying ever so hard to hear it?

I love my XP-60 - so do tens of thousands of 60 - 80 owners around the world.

In my (amateurish and ill-informed) opinion this is a theoretical problem, not an actual one.

My ten bob's worth, anyway.

Martin

Yeah, really; all synths are apparently not created equal, since my XP60 has never exhibited this phenomenon. This whole thread has always puzzled me. And FWIW: I think the Roland UK techie's "no gating" explanation is a bit spurious.

I posted this message on this board about a year ago..

"I have just done some "research" on the much discussed decay noise/distortion on the XP/JV synths, and I thought I should publish my findings. I own an XP-60 that I used for these tests.
As the sound on the XP-60 decays, a slight noise/distortion may appear. Some users have blamed this on the D/A-converters, others on the synthesis engine itself.

I used a piano-patch that I know has this noise on the decay. In tone 4 of the patch, I included a sine waveform and assigned it to the lower part of the keyboard. I limited the piano to the upper part, so that I got a split. I adjusted the sine so that it was in a different part of the frequency range than both the piano and its decay noise. (A sine only contains one frequency, so that it is easy to separate from the decay noise and the piano). I turned the tone volume of the sine down really low, as I have to turn up the volume of my amplifier to hear the decay noise at all.

I then tried to play a note with the piano patch, and let it decay. At the same time I increased the volume of my amp towards max. As the decay noise/distortion appeared, I tried to tap a key on the lower part of the keyboard, assigned to the sine waveform. With brief taps on the key with the sine, I could clearly hear the decay noise disappear! It reappeared the moment I released the sine.

From this I conclude:
The decay noise is not in any way related to the synthesis engine itself. The noise/distortion appears when the TOTAL signal-level of the output drops below a certain level. I have heard users complain about hearing the decay-noise all the time while playing e.g. sequenced songs. This must be a problem of their hearing, or the placebo effect!

The decay noise does NOT appear at the end of every note played, and is not really related to decay (in the synthesizer meaning of the word) at all. It is only related to the outputs. This means that in a typical sequenced song, the decay noise will appear for the last 2-3 seconds of the song, when the total level is dying!! Other than this, the outputs will mostly perform perfectly. Playing in patch-mode (with percussive instruments), the noise may appear slightly more often.

Decay noise of this kind seems to be quite typical for digital instruments, exactly the same symptoms were discovered in a Technics KN-920 keyboard. Only worse...

It may not even be the D/A-converters that are to blame. Perhaps there is something in the analog part of the output?

Some users have claimed that this very minor fault in the XP/JV-synths make them unusable for professional purposes. Well, if it's pro enough for Jean-Michel Jarre (XP-80 on Metamorphoses), I must admit that it is more than pro enough for me!!! But perhaps we have some REAL pros on this message board? "

End of (my own) quote..

Hope this information was useful.....

Stig

dnarkosis

Are you absolutely *sure* !?
Have you tried listening to a
e.g. Piano patch on decent headphones
and played quietly and with
the volume turned right up ?

And then listen to a slow decaying note
right to the end ?

No fuzzing, no fizzing - not AT ALL ?!!

If so when & where did you buy your XP-60 ?!

Maybe they've fixed it in some XP-60s but
wont actually admit it !?!


Alec



[This message has been edited by stewart33 (edited 03-17-2001).]

stigf

Interesting. Are you saying that this effect
only happens when the *total* volume of output approaches zero ?

So that if for example I had a very very quiet note running through - a bit like a background hum - then we wouldnt experience this effect ?

Either way I'm not sure what to conclude !?!
I shall go back and test my XP-60 and see if
it's the same effect on every single key on a piano patch.

But I'm particularly interested in
dnarkosis's post saying that his machine is fine. Do we believe him ? Because if it is fine, then I can shout like bl**dy h*ll at Roland, (though if it isnt I'm in trouble!)

A

The problem is the cheap d/a convertors. Roland will do nothing about it.

The problem effects all xp60, xp80,xp30, jv 1010 and jv2080.

Listen with headphones at high volume, with effects on in quiet environment, especially on accoustic guitar and piano patches.

stewart33:

That is exactly what I am saying.. Try it for yourself..

If you had a background hum or something, that stopped the sound from dropping below a certain level, then the problem would not be there at all.. Which should, as I said, that the problem is NOT in the samples, but in the output...

And people:
This may sound rude, but let's try to listen too hard to Arvon45 in this matter. He has shouted about this problem for 2 years on ths board, and has come up with nothing constructive. I think he sold his XP years ago, and is now a Korgian...

Stig

By the way..

My XP DOES have this problem, but i find it so minor, that I don't care. Most other noise-sources are far bigger..

If this has been a problem with all XPs/JVs, then why was it discovered only a couple of years ago?!?!

Maybe because it is so minor...

Stig