Re: [ARSCLIST] (dream) restoration phono preamp opinions wanted

[Robert Hodge <rjhodge@xxxxxxx>]

About the only part that could fail without being easily available
might be the power transformer. The filter caps , rectifier and dividing
resistors  are commonly available. 
And although I've rebuilt a few of these , I've never found one with a
bad transformer.

Best !

Bob Hodge

Robert Hodge,
Senior Engineer
Belfer Audio Archive
Syracuse University
222 Waverly Ave .
Syracuse N.Y. 13244-2010

315-443- 7971
FAX-315-443-4866

>>> johnross@xxxxxxxxxxx 4/4/2007 2:57 PM >>>
Powering C-8s is not a problem for me -- I own four (count them, 4!) 
Mac 20W-2 power amplifiers that do the job just fine. And they too 
have a hum adjustment pot.

Just offhand, I'm guessing that finding a D-8A power supply today (or 
a D-8, which would also work) would be far more difficult than 
finding a C-8 preamp. I found a couple online, in the $300 price
range.

John Ross

At  4/4/2007 11:27 AM, you wrote:
>Hi John,
>
>Just FYI, Mcintosh built an external power supply called an D-8A
>that will run the c-4 or c-8 beautifully.It has a hum balance pot
that
>is effective in minimising hum. Note minimising !!
>
>Hope this is usefull. Or buy the parts and build one yourself.
Nothing
>special.
>
>Bob Hodge
>
> >>> smolians@xxxxxxxxx 4/4/2007 1:20 PM >>>
>I've been working some from mono LPs to master to CD.  In my
experience,
>accurate recording/playback eq is imprecise at best, and, quite
frequently,
>imaginary.  Further eq is always needed.
>
>I've encountered a specific situation where I've had three issues of 
>a Period LP, all mastered before 1959, each with its own eq.  One 
>was early, probably Columbia, c. 1951, for which I used the LP 
>setting. Another, mastered by RCA with the type in 1954 in small 
>block letters and numbers, used NAB,  a third, using the same RCA 
>matrix number but handwritten, fell in the cracks somewhere. I used 
>RIAA and adjusted a whole lot with an equalizer.
>
>Tube equipment has hum- it's genetic!  It should be removed during 
>the restoration process.  If you prefer your finished audio with 
>tube sound, ok.
>But don't plead accuracy.  You are deliberately including non-musical
noise.
>
>In short- you know the answer.  Listening.
>
>Steve Smolian
>
>
>----- Original Message -----
>From: "John Ross" <johnross@xxxxxxxxxxx>
>To: <ARSCLIST@xxxxxxxxxxxx>
>Sent: Wednesday, April 04, 2007 12:31 PM
>Subject: Re: [ARSCLIST] (dream) restoration phono preamp opinions
>wanted
>
>
> > At  4/3/2007 10:24 PM, EricJ wrote:
> >>When it comes to phono preamps that are capable of
> >>historical EQs, I was wondering...
> >>
> >>1.  How many people use anything but RIAA, NAB, and FLAT
> >>     EQs for digital transfers when doing preservation work?
> >
> > For 78s and pre-RIAA LPs, I generally use a tube-era preamp that
has
>
> > front-panel adjustments for Turnover and Rolloff. A McIntosh C-8
is
> > particularly flexible, but it requires an early Mac power amplifier
as a
> > power supply. I also like my Scott 121-C, with the Dynaural Noise
> > Reduction function. I wouldn't use the noise reduction for
preservation,
> > but it's nice for casual listening. Of course, any tube equipment
of that
> > vintage almost certainly needs to be re-capped before you would
want to
> > use it for serious work.
> >
> >
> >>2.  Is the ability to reproduce a wide range of EQs on the phono
preamp
> >>important, or do you apply the final EQ in the DAW using digital
filters?
> >
> > I think either approach is acceptable, as long as the EQ is
correct.
> >
> >>3.  Do you use an analog processor in conjunction with your DAW to
apply
> >>EQ later to a FLAT digital transfer (ie. an analog processor
loop)?
> >
> > No.
> >
> >>4.  How often do you run into the situation where your phono
preamp
> >>doesn't have the EQ you want?  It gets close, but not quite what
you want.
> >
> > That is not an issue with either the Scott or the McIntosh
preamps.
> >
> >>8.  If the phono preamp has accurate EQ(s), is quiet, and has low
> >>distortion, does anyone prefer tube versus solid-state electronics?
Does
> >>this matter?
> >
> > Obviously, I'm partial to tubes, but for RIAA  EQ, I also use
solid-state
> > (including a McIntosh C-24, a Stanton 310 and some other broadcast
preamps
> > with balanced outputs
> >
> >
> >>9.  Do you use a custom-built phono preamp or a commercial phono
preamp?
> >
> > They're all commercial devices.
> >
> >
> >>And if there's a phono preamp that supports historical EQs that
you
> >>really absolutely love, let me know, because maybe I should be
buying
> >>instead of building.
> >
> > As I said earlier, I like both the Mac C-8 and the Scott 121-C.
> > Unfortunately, both are subject to the demands of the loony
collectors'
> > market, so the prices are out of line with their value as playback
tools.
> > You can find relatively inexpensive C-8s, but they're useless
without an
> > expensive MC-30 or 20W-2 amplifier to supply power to the tubes.
> >
> > John Ross