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(Scott Dorsey) wrote in message ...

......what was posted were only some offhanded comments
I made to Luke.

Which he posted as a "pre review" in Luke's words. Seeing as you
weren't finished with you evaluation it seems hardly responsible on
Luke's part but rather more like champing at the bit to post negative
comments. He posted it with the disclaimer that you (Scott) rarely say
anything really good regarding your review subjects but that your
readers "understood" this and would take these comments as a good
review. But RO members are not familiar with this aspect of your
review style. Really not fair. It's unfortunate that you are getting
painted with this paint brush because of Luke's pre mature
ejaculation.

I didn't see any secret technology myself, or anything particularly unusual,
but since I didn't have full schematics, the little that I know I got from
reverse-engineering the board, and I did not do a full or complete job of
this.

As I already have pointed out, you were not finished with the review.
I would very much like to see it when you are finished. I might even
publish it if you didn't mind.

It's built on a 4 channel PC board made from the Express PCB system,
with only two channels stuffed. This means it should be fairly easy to
upgrade from 2 to 4 channels later on. I like that a lot although it
probably increases the price of the 2-channel version considerably.

Actually, the vmp was designed as a 2 channel unit (which sells for
$1450 USD) from the start. The vmp 2000 is a more affordable scaled
down unit.

Input stage is a rather depressing 1:10 transformer going into a 2-triode
12AT7 configuration. Square wave response of the transformer is not so
good, but again the transformer is an easy thing to replace.

The transformer was intentionally designed that way to produce the
sound the vmp yields. I like it quite a bit myself and wouldn't want
it to change.

(In the thing that was posted to the RO forum, I had said it was a
"12AX7" meaning basically that general sort of dual triode family, and
that is one of the things I was flamed about. It is indeed a 12AT7,
though.)

Yes it is unfortunate Luke posted the comments before you were
finished with your evaluation and before you had given Sebatron an
opportunity to address your comments, prior to publishing. You do that
don't you? Every reputable review I have ever seen does.

The output stage looks to be solid state, but I have not drawn the schematic
for that stuff out yet. I assume they are doing this rather than using a
tube follower in order to reduce the cost of the power supply. I don't hear
anything bad going on with this.

The overall sound is okay, but it is very clear that the input transformer
is the real bottleneck in the sound. Upgrading the input transformer would
be a really good idea.

Once again, I like the sound as it is. It is different than other pres
and I enjoy the variety instead of it being another "me too" product.
I think the sound on acoustic guitars is phenomenal. You can check
some sound samples I posted at RO. It costs nothing to register. The
samples of the Sebatron as well as many other pres are in the Audio
Projects streaming critique forum. Drop me a pm while you are there
and say "HI!"

The power supply is a little bit undersized too, I think. They are also using
two power transformers; if this is going into any kind of production volume,
they can actually save considerable money by going with a custom power
transformer on the unit. Also, using a little PC board on the front panel
rather than hand-wiring it can cut the manufacturing cost considerably.

Seb uses point to point wiring intentionally, regardless of the costs.
he thinks, as I do, this kind of approach just sounds better, ala'
vintage Fender amps vs. newer PCB designs. Large traces are
implemented on the PCB for lower voltages but all high voltage paths
are point to point wired.

The overall design is a good one, but I was really disappointed in the input
transformers. It would cost THAT much to install Jensen or Cine-Mags in there, and the sonic improvement would be considerable.

Once again, the trasfos are that way on purpose. Part of the sound.
Changing it would only serve to defeat the unique sound and put the
pre into the "me too" realm.

The real dominant sound of the thing is the input transformer and it is
really difficult to hear beyond that. It's definitely a lot woolier sounding
than it could be... I think a good input transformer would bring a lot more
detail out.

As I said, I love how it sounds. Evidently so do a lot of other
people. Since I reviewed the vmp 4000 at RO, the demand for them has
shot up trough the ceiling. Sebatron has recently announced that he is
moving to a new facility ten time the current size, to accommodate the
demand.

Anyway, this posting is apt to be greeted with a lot of flames and such
and more information about some new proprietary technology. There might
be something new and amazing going on here that I missed, but a proprietary
technology you don't talk about is not particularly helpful.
--scott

Scott, No flame here. I chose to assign the blame where I feel it
belongs, with Luke. You were essentially innocent in all of this. It
was Luke who was anxious to flame Sebatron and RO, I think because of
his affiliation and friendship with a well known gear dealer who as
Luke himself stated, use to mod at RO. This gear dealer has a rep for
bashing products he doesn't carry, part of the reason he was asked to
leave RO, and because of this has a grudge to bear against the
administration at RO. Unfortunately, it seems you got caught up in all
of this. I would like to offer you, as Editor of Reviews at RO a
chance to write reviews for us. I can be contacted thorough the PM
system at www.recording.org. Sincerely, Kurt Foster