Dear Mark,
I will try to add some insight to the evolutionary nature of things. If you will
remember, I invented the "Record Rack", which is what Dynaco people called the
400 heat sink array however, I don't believe that anyone was dumb enough to put
records in there. The priciple confused alot of people at first because no one
could understand how it could work because there were NO holes in the bottom of
the hear sink assembly. As a matter of fact this heat sink assembly was
incredibly efficient although not cheap. Anyone who wishes to know the theory
behind it should contact me.
Needless to say, I designed the XXXIB, the IIIC &CM, and the IVD & DM with the
same functional intention. The efficiency of the heat sink assembly however,
never approached what I got with the Dynaco assembly due to the following
reasons. The Dynaco had true extruded fins mounted on an extruded double T
platform. The SAE units used a harder metal that was fabricated into "U" shapes
in the SAE metalshop. This would have been acceptable, however, Morris insisted
on "time-
saving" (achieving the brushed finish before anodizing) in order to make the unit
look nice. Unfortunately this left thousands of little ridges between the layers
which reduced the efficiency. This was however, NOT A PROBLEM FOR HOME USE. In
our testing at the time, we were never able to overheat the amplifier on normal
music signals and indeed, thousands of these units were made and had NO thermal
problems.
When Morris wanted to support the pro world, where the dynamic range is severely
restricted and compressed, this made the amplfiers run alot hotter hence the need
for the fan. Othere than that, the units were absolutely identical. I want to
stress here that the Dynaco design was massive overkill whereas the SAE units
were more practical. The only thing that I would recommend at this time which is
some 25 to 27 years later, is that anyone with one of these units should have the
amp disassembled by a competent technical person who can completely remove the
old grease that has long dried out, and replacing with new thernal grease. This
would probably add significantly to the life of the unit. I will repeat here that
in my not so humble opinion, these three amplifiers were the best amps (sonically
as well as measuring) that SAE ever produced. The 2400 was virtually a carbon
copy of my Ampzilla circuit value for value which says volumes about the original
which was in itself almost a carbon copy of the SAE circuits.
James Bongiorno
gurriesm wrote:
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From: gurriesm <gurriesm@...>
akble@... wrote:
From: akble@...
Hi guys- Guess i should be politically correct and ask in if any ladies in
group rather than to assume not.
Anyway own a number of the the original series Mark items in light colored
front panels. Last week noticed in local paper add for SAE equipment for
sale- Called and he had 2400L, 2800, Mk1 and 8000 tuner. Original owner with
boxes and manuals. Picked up them up along with his 901's real right.
The only item in group I am a little short of info and knowledge is the
8000. Is it primairly a MK VIII in rack mount front? or closer to to 3200?
When was it built?
Any feedback will be appreciated.
Thanks
Andy
Hello Andy,
James Bongiorno, who is the key SAE designer engineer would be the best
person to answer this. But I will give you what I believe to be true,
but welcome corrections.
It is my understanding that the tuners are the same except for
evolutionary circuit improvement and changes. The 3200 is a completely
different tuner that I believe was addressing the lower cost needs of the
home consumer since the 8000 was becoming to expensive for main stream
sales. Anyway, the sales literature does indicate a small semiconductor
circuit change between the MkVIII and the 8000. The 8000 had one less
transistor in the RF front end yet the specifications between the models
remained the same. However, sales literature sometimes have mistakes in
details like this. So I cannot be sure about the circuit changes at all.
Anyway, for all practical purposes they are interchangeable products.
The model number change is nothing more then being part of the marketing
movement to make the SAE product line sound more Pro.
Here are some of my personal thoughts based on limited available factual
data and some conjecture on my part.
Historically the difference between the Mk xxxx (Ex: Mk VIII) line and
the xx00 or "thousand" (Ex: 8000) line was the marketing. The Mk
product is supposed to me the original and older consumer home line and
typically lacked the rack mounting option and came in two tone or solid
clear/gold alodyne brushed aluminum surface (light color). The later
"Thousand" line was the pro version with rack mounting and came only in
dark black brushed aluminum anodize color. Internally the models are
identical for all practical purposes and were built on the same
production line. But from a sales point of view, the pro version took
over the product line since, I believe, it was viewed as being more of a
high end and robust product. But there clearly there were transitional
models that become pro in terms of color and rack mounting but yet
retained the older Mkxxx number. For instance, I own a black rack mount
MkXXX1B amp. The original early MkXXX1B production version was clear
alodyne with no rack mount option. You can see the evolutionary changes
by looking at the difference in the yearly full line SAE catalogs. For
the transitional high power Mkxxx amplifier models, the pro version came
with a cooling fan installed whereas it was only an option for the home
line. Specifically I am refereing to the MkIIIC and MkIIICM 200W/Channel
amps. James, any comments here?
Best Regards,
Mark Gurries
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Battery Charging and Power Systems Application Engineer
Linear Technology,1630 McCarthy Blvd, Milpitas, CA, 95035
WRK(408) 954-8400 x3864 Email: gurriesm@...
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