Ok - I've been on a phono preamp "bender" as they say...

For the past few years, I've been testing phono preamps.
Lots of them.  I use the Millennia Media LPE-2, Elberg 
MD-12, and even a Boulder 1010 (RIAA only) phono preamp.
I've tried many others.  For RIAA work, I have tested 
close to 2 dozen phono preamps.

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?

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?

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)?

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.

5.  Do you care about being able to control Low Bass EQ? 
    (ie. turnovers of 40, 50, 60, 70, 100 Hz)

6.  What other analog processors/filters do you use with 
    your phono preamp?  (ie. shelf?  high-pass? other?)
    Do you use these often?

7.  When doing re-issue work (not just listening/monitoring), 
    do you sum L/R for mono using the mono/stereo switch on 
    the phono preamp, or do you always do this in the DAW?

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?

9.  Do you use a custom-built phono preamp or a commercial
    phono preamp?

I'm at the point where I'm really unhappy with the sound of most
(all?) of the commercial phono preamps available that support 
historical EQs (and many of the RIAA-only phono preamps, too), 
and am ready to commission a custom phono preamp.

So before I go off and just spec a phono preamp in a vacuum, I 
wanted to see what other people like or need, just in case I 
overlooked some critical features.

The features that I've spec'd so far:

   - 0 dB (processor mode), 32 dB (mm), 62 dB (mc) gain settings
   - separately adjustable Low Bass, Bass, and Treble turnovers
     (FLAT + 5 EQs for each)
   - Low Bass EQ pre-sets: FLAT, 40, 50, 60, 70, 100 Hz
   - Bass EQ pre-sets: FLAT, 500, 400, 300, 250, 200 Hz
   - Treble 10 kHz roll-off presets: FLAT, -16.1, -13.7, -12.3, 
     -8.6, 5.4 dB
   - precision pre-made EQ plug-ins (individual Low Bass, Bass,
     and Treble) that can be inserted without opening the case
   - Bass EQ plug-ins: 150, 353, 450 Hz
   - Treble EQ plug-ins: -10.82, -10.35, -11.4, -7, -6.35 dB @ 10 khz
   - +/-0.2 dB EQ accuracy
   - Lateral and Vertical groove switch
   - balanced and single-ended outputs
   - RCA and XLR jacks for phono input (allows line-level balanced
     inputs for analog processor mode)

Some features I'm not so sure about (although philosophically, I'm 
trying to keep the phono preamp as basic as possible, with the 
exception being the EQs, which I prefer to do in the analog domain):

   - no Mono/Stereo switch (I normally do this in real-time at the 
   - no Left/Right groove wall switch (I normally do this work in the 
   - no high pass filter (I do all of my noise reduction in the DAW)
   - no low pass filter (again, done in the DAW)
   - only 1 turntable input (trying to minimize the number of switches
     and connections)
   - no mute switch (minimizing switches...)
   - no balance control (do this in the DAW...)

What other features would you put into your dream phono preamp?  Am
I missing anything really important?

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.

Finally, in the process of commissioning a phono preamp, I've listened
to dozens of RIAA-only preamps on a reference system in a reference
room, listening primarily to 1950s monophonic orchestral recordings as
well as simply mic'd (Blumlein) stereo recordings.  I'm now approaching
the makers of my favorite phono preamps to see if they'll do a one-off
phono preamp with variable EQ to my specs.

Thanks in advance!

Eric Jacobs

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