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I have a ZETA electronic violin. It has the Jazz performance bridge, which is designed to work well for MIDI due the double piezo pick-ups per string. These pick-ups (per string) are mounted at approximately 90 degress from each other and arranged into a V shaped well, into which, the string sits. This causes, amongst other things, a certain cancellation in bow noise, as well, a reduction in the amount of overtones, or at least, their relative level against the fundamental. Now the reduction in violin overtones gives the Zeta a rather lean quality which isn't as pleasing as other types of electric violin pick-ups which use a standard piezo element within a real violin bridge. However, I chose the zeta because I do a lot of experimental DSP processing and only the Zeta jazz pick-up will work satisfactorily in these cases. As an example, a complex delay algorithm with natural bow noise really interfers with the process as well as most other types of FX processing. The problem with my instument is as follows...If I plug into a standard guitar combo amp with twin tens or twelves, the sound is generally pleasing due to the colored circuit and speakers which "low pass" or roll-off the output. But if I connect it to a quality mastering chain with precision electronics (solid state), it is very, very dissapointing, producing a sound that is extremely clean (free of noise), lean, as in a raw analog synthesizer oscillator producing a thin saw wave output. The Zeta has an active nine volt battery preamp board within the instument body which uses IC opamps (don't know what they are). The onboard pre is hot enough to drive line level minus 10 dBu unbalanced inputs. What do you know about the Sebatron with this kind of source? I really need to change the overall character of my instrument. As mentioned above, I get interesting results with the colored setup of the guitar combo stuff, so its sonic signature can definitely be altered, but I need to get more of that signiture with line level recording inputs? BTW, are you series of preamps the same sonically...4 channel, 2 channel, etc.? Can you state some basic electrical specs such as input imp., output imp., noise floor, nonimal/max output levels in dBu, etc.
Thanks in advance,
Phil

[ December 24, 2003, 06:50 AM: Message edited by: phil magnotta ]

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audiokid Tue, 12/23/2003 - 22:12

Hi Phil, rename the title to this thread to "Violin" instead of "New Member, Important Question: " It will draw a better crowd.

I'm no violin pro but I'd say your on the right track looking in here. It is my experience that violins in a solid state path sound soooo thin and annoying to say the least. I'm looking forward to other comments on this topic.

Sebatron Wed, 12/24/2003 - 21:50

Yes very good question.
Yeah, basically you need to fatten up the fundamental which i assume as you've described wouldn't be too far off a raw analoug synth oscillator.
I feel that at least two channels of vmp circuitry linked in series would certainly get you closer.,..simply from the unbalanced out to the d.i input of the next channel.
The idea would be to drive the second channel significantly by the hot output of the first channel.Activation of the 'deep' switch would help as well , although its peak frequency is lower than the desired frquency you need to push.

Somehow you need to boost 220hz to 800 hz region to get the presence and then start a roll-off around 4khz - 8khz.

Good results , i feel , would be attained by patching an E.Q ( grahic or parametric ) in between the two channels although it would have to handle a fair bit of dynamics.
You could also try e.q at the start before it hits the valves.

If you are slightly skilled at soldering you could actually re-configure the vmp E.Q to act as a low-pass filter.

Here's how:
Where the two ceramic capacitors meet the 56K resistor near the D.I input ,, simply snip those ends and solder to an earth point ( ..right near the tag-strip )..
This would invert the air/bright function of the E.Q to low-pass 'subtle and heavy'.
..by adding more capacitors on top of the exsisting ones , you can make the roll-off heavier/steeper.
Upon request i could modify a unit for you.... hell , i'd even 'tune' one up on an electric violin.

Alternatively , we have just completed prototypes of our new unit called DEUTERIUM.
This is a single-channel four gain stage valve D.I with interesting E.Q.Designed for max valve colour and situations like this where organic sonic enhancement are needed.

XMAS :w:

anonymous Fri, 12/26/2003 - 12:58

Thanks Sebatron, for you reply.
Of course, I'll have to try the Sebatron unit.
A few questions please:

I downloaded both the 2000e and 2000e VU owners manuals. There is no diference between the two. I was hoping for info on the balastics behavior or design of the meters since there has always been a general lack of understanding about so called VU meters. There is, of course, a type that is refered to as a "true volume unit" meter, but I forget how it is designed. You should state something about the meters.
In my opinion, there is a lack of technical info on your units such as I/O impedances, I/O levels,
S/N ratios, Frequency responce/distortion...Yes, I know that freq responce/distortions (at least) in these type of units can be other than flat, however, from what I see here in the forum, there seems to be an operational condition where the unit is in its most neutral performance, so that would be a good position to look at.
Also, the pads function(s) is not clear to me because it is apparenly more than a netrual pad.
I respecfully request you reconsider a clearer approach to the manual and provide some specs. I know that others have found the manual a little lacking. To be fair, since I don't own the unit, the vmp series may indeed be self explainatory under operation-or so varied in its performance and surprising/satisfaction, that all of the above be unnecessary..I'll have to wait and see.
Sincerely,
Phil Magnotta

Sebatron Sat, 12/27/2003 - 23:27

the vmp series may indeed be self explainatory under operation-or so varied in its performance and surprising/satisfaction, that all of the above be unnecessary..

...that's kind of it.
We figure if you don't know how to work it , then you shouldn't get it.

The specs. of the vmp have varied alot due to an ongoing design ,,. for example recently we made a change to the gain of the unit.
The newer design also features a flatter frequency response than the one used in Kurt Fosters review , and audio samples.

VMP mic pre specifications :

Mic Input Impedance: 600 ohms
D.I Input Impedance : 56 kilo ohms

Output Impedance:

Frequency Response: 14 hz to 88 Khz +/- 2 db
Signal to Noise : 76 db minimum
Maximum Gain: 55 db -60 db
Noise Floor: EIN

Maximum input :
0 pad -10 db
-15 db pad +5 db
-30 db pad +20 db

Maximum Output:
Balanced: +28 dbm
Unbalanced: +22 dbm

Bright Shelf:
0 pad +5 db @ 11.8 khz
-15db pad +9 db @ 20 khz
-30db Pad +8 db @ 16.8 khz

Air Shelf:
0 pad +4 db @ 14.5 db
-15 db pad +9 db @ 26 khz
-30 db pad +6 db @ 20.6 khz

Deep Shelf: +8 db @ 40 hz

xmas :w: