Zuma question

[duomo]

hi there all zuma users,
I have a problem setting up my zuma. It came back from repair. I didn't used it before because I bought it brocken.
Now I did all adjustments and all the wiring which is need to integrate it. I did the whole tests and adjusments . Everything worked fine so far, but starting the LL adjusments with a mono test tone, I have also an increase on the depth meter.withou signal its 30 mv and with mono signal its nearly 40 mv, but there is no stereo information. I've tested my input signals, everything was ok., no L/R anomalies .
I have software version 1.6 I think. Is this normal ? is it a wanted effect ( louder cuts -> deeper grooves) ? .
Thanks for your help !!!
all the best
Moritz

[cohearent]

Hi Moritz,

No. Something is wrong. Are you sure the signals to the Zuma are in phase/polarity? That would cause it.
Also are you sure both channels are going to the Zuma, and I mean check at the analog audio board in the Zuma, the one all the way at the back, not just at the XLRs. One channel only looks like a lot of "difference" information which would increase depth.
If you have signal there, it is still possible you have a bad opamp or other component on that board. If you can feed in a 1K tone and start checking from one opamp to the next with a scope or meter. Let me know what you find.

Best,

Kev

[duomo]

thanks for your help kev,
I'll check the polarity of all inputs when I'm back in the studio on Monday. I hope that will solve the problem.
One more issue came me in mind. What is the correct delay time ? I fond nothing in the manual for version 1.6 which is the last one published I think. in version 1.3 there should be 0.6 revolution as delay. But I see that version 1.6 has only one stereo pair on the I/O card just for the preview signal, the modulation signal is generated inside.. so its logic that there must be a delay, isn't it ?
thanks again..

[cohearent]

Yes, 1.6 was the last version. And yes, it was designed for .6 rev preview as was the lathe and all Zuma versions. The first Neumann lathe to deviate from that was the VMS80. You are also correct that it delays preview to create the Left Modulation signal needed by the stock Neumann.

[gold]

If what Kevin suggests checks out as good you could try measuring the LL, LV, V control voltages at the output of the Zuma. If all control voltages look correct it is most likely a wiring problem in the lathe.

[duomo]

Thanks, all it was a great help!
the input card of the zuma had a very little difference between L and R I calibrated the inputs by reading by looking at the depth meter, now its fine.
I'm still a little confused because of the delay time.
If I set it to 0.6 revolution ( 303 milsec) and try to calibrate the V Programmer the depth change happens a quarter revolution too late. So the preview delay has to be longer I think...
did I calculated the milsec wrong ?
Do anybody have the pulse tones for the calibration ? I now used the pitch tones from flo kaufmann but there in some frequencies I have overcuts and on others I don't ... mhhhh
When I cut music everything looks fine so long , but the whole thing feels a little too insecure...
Thanks again...

[duomo]

0.6 revolution ( 303 milsec)

ahh I found my problem, its not /6 but .6 which means 60% of one revolution, which means 1,1 sec...

but to know the exact specs of the pulse testtone of the ZUMA Tape would be great if anybody knows..

[dietrich10]

I have also have my delays at 900ms for 33rpm and 666ms for 45rpm.
is this not correct?

[duomo]

No I found the specs in the original Neumann Manual:
33,3 -> 1,1 sec
45 -> 0.84 sec

[opcode66]

@Duomo - Those values are for the Neumann Pitch and Depth computer. Not necessarily the values used by the Zuma. I have a Zuma manual if you want me to email you a copy of the PDF let me know.

[dietrich10]

I have the zuma manual just questioning after some posts on here

[duomo]

Thanks I have the Zuma manua too, (but not complete) but I found out thats the same falue asked by the zuma (0.6 ref) .
After some more calibration checks I'm now on status GO

[duomo]

I now cutted the first two lacquers with my new ZUMA and everything works so far. I also did a "battle" between my old vg66 pitch and the ZUMA. it was a 5 min song the discspace of the TP cutted with the old vg66 was 2,1 cm with the ZUMA it was 2 cm.... mmhh not such a huge improvement. I selected a very dynamic song, because I thought the difference is bigger then..
Any Thoughts ?

[flozki]

get proper test tones and verify if your system is ok.
even with the best pitch you wont gain a lot if the track needs the space.

for creating the pitch98 algorithm , jvo made a simulation software to simulate the best 'theoretical' case.... it was made for mathlab on old mac...
something like this would be best.
also on the latest update he made a rest time calculation which matched in all cases i was cutting with it. so the theoretical space needed for a certain track can be calculated extremly exact.

the problem is to know what exactly does the zuma and the neumann original, or any other system..
for neumann orignial it is quite clear, but unfortunately because of various design errors it will never match the reality...

but there are definitely many cases where you gain little to nothing.. except comfort of cutting..which i guess is way better with zuma than with original neumann system.

so best is to use test tones. when that works fine you can not that much better.
some basic test tones we use for pitch98 can be downloaded on their ftp..
but i dont know by heart the adress..

[concretecowboy71]

If there is little or no gain by using the Zuma, what is the advantage of using it?

Perhaps I am not reading the posts correctly, but why spend extra money on something that has no value?

I would love to hear more in general about the advantages of aftermarket pitch and depth.

I run my lathe stock and have never had an issue. I have cut sides up to 32 minutes with no issues.

[flozki]

i guess you missunderstood
in lot of cases you can gain a lot with a good pitch.no question. i would not miss it. although a fixed pitch cut looks so much better....
but there are also many tracks with little gain.sometimes it just needs that space and then even a good pitch doesnt help..
for example if your main bass is close to99 hz you will have peak exactly on peak... so then no pitch can do more than make the correct speed for the land and with adjusted....

so it is always hard to make a performance test with only a music track.

with testtones you can check if all works fine.
just with music ..quite difficult

there are for sure good audio tracks to test. but again..so many other parameters...

[Zuma Group]

Not all Zumas are alike. Most Zuma's were programmed for a .6 revolution delay, so for 33 rpm it's 60/33.33 *.6 = 1.08 seconds. For 45 rpm it's 60/45 * . 6 =0.8 seconds.

However several Zumas were built for .5 revolution delays for cutters that also VMS 80's in house. These of course will require a different delay time. You do the math.

Some Zumas were built for 50Hz line frequency, they will not work properly on a 60 Hz line, nor will a 60 Hz Zuma work properly on a 50 Hz line. The internal timings will be wrong.

Finally some Zuma's were built for JVC and Panasonic quartz drives and they require that the lathe have these motors to work properly.

The EPROM label will tell you what you have.

John B

[Zuma Group]

so best is to use test tones. when that works fine you can not that much better.
some basic test tones we use for pitch98 can be downloaded on their ftp..
but i dont know by heart the adress..

For the basic Zuma calibration, just record some mono 200 Hz 500 mS pulses about 3 or 4 seconds apart. You'll use these to set LL. Record a steady out of phase 200 Hz tone to set V and LV.

See manual for details.

[Zuma Group]

If there is little or no gain by using the Zuma, what is the advantage of using it?

Perhaps I am not reading the posts correctly, but why spend extra money on something that has no value?

I would love to hear more in general about the advantages of aftermarket pitch and depth.

I run my lathe stock and have never had an issue. I have cut sides up to 32 minutes with no issues.

First of all, it's nearly impossible to compare cuts between systems unless extreme care is taken in the setup and the comparison.

Second, as already pointed out, certain material will show greater benefit over the stock system than others. In general, the benefit is more obvious with material with deep bass and pronounced channel separation.

Most importantly, despite the typical emphasis on higher levels and longer sides, the main benefit is a reliable perfect cut, without overcuts or lifts, something that the stock lathes were incapable of providing with any consistancy

John B.

[duomo]

Some Zumas were built for 50Hz line frequency, they will not work properly on a 60 Hz line, nor will a 60 Hz Zuma work properly on a 50 Hz line. The internal timings will be wrong.

oh shit, my zuma runs with 110V and was used in the US before so I think my line frequency is wrong ( I'm in Germany) so I have to look for a frequency shifter. Or is it possible to change the line frequency setup with a jumper internally ?

so best is to use test tones. when that works fine you can not that much better.
some basic test tones we use for pitch98 can be downloaded on their ftp..

Thanks flo I already have this pitch98 testtones, I used them for calibration...
worked fine so long, I now do the pulse test too, but at first switch the frequency