Recording - April 2017 - 63

Series EQ and PSP Audioware PSP E27 and PSP E27 SE
inductor qualities to it. It's partially why the E27 has this rich
second- and third-order harmonic distortion; not at the frequency center where you boost it, but around that frequency.

I remember that by 2008, the E27 had developed a
very dedicated following, but around 2010 or 2011
they were discontinued. What happened?

I just got really busy. Around that time, Brent Averill sold his
company so I was helping out BAE for about five years with the
transition, developing the product line. When I was designing
for BAE, I just couldn't have time for making the E27, so I had
to discontinue it.
When Mark [Loughman] had BAE going strong, I was able
to fade from there and get back to spending more time at my
own shop. Later, I got some great help with Jeff Watson and I
brought it back again.

I know lots of folks are glad you did. Lastly let's talk
about the plug-in from PSP; how did it come about?

A friend of mine said, "You know, this EQ should definitely be a
plug-in." And I thought about it and I said, "Yeah, it's unique enough
in its circuitry, it could happen." So after considering a few companies,
my friends said, "This company from Poland, PSP, they're really good."
At a NAMM Show, I went over to their booth and introduced
myself, and the possibility of making the E27 into a plug-in.
They thought about it, and by the end of the day they said,
"Yeah, I think we would be interested." So I handed them an
E27 right from my booth and they took it to Poland, and for that
entire year we worked together. I sent them THD graphs from
an Audio Precision analyzer, and I sent them schematics, and
they used those to program the algorithms.

...and PSP Audioware's Mateusz
Wozniak on the PSP E27
Mateusz, this is PSP Audioware's first one-to-one
model of a specific hardware piece since the Lexicon
PCM 42. Why have you waited so long to do a specific
model vs. the hybrid approach you have been taking?

Mateusz Wozniak: We are a company grown mostly on our
own experience and solutions inspired by good gear. Even if we
do a plug-in based on hardware we still like to have an influence
on its final shape, adding extra features and so on.
Doing specific hardware is a different story. In this case we have
to strictly follow its behavior, study schematics with care, and do
a lot of detailed measurements, instead of looking for a solution
which best meets our needs. Sometimes a decision to make a specific hardware piece is a matter of luck. We need to be inspired by
a piece of gear and need to have a relation with its designers.

Were there any challenges creating the E27 plug-in?

We usually try to do plug-ins which allow us to learn something
new, like the E27. Adam Taborowski (the main developer and

I did some side-by-side comparisons with the real thing
and the plug-in, and frequency-wise, they totally nailed
it. In fact, the only thing I noticed was a bit of hardware/
plug-in level difference when boosting or cutting.

Yeah, you're spot on. Your ears are not lying to you. We
noticed about a 1.2 dB difference between the E27 software and
the hardware, given the same frequency. The hardware is louder.

I was most impressed by how smoothly they matched
the 28 kHz band.

That took Adam at PSP Audioware some time to figure out, and
it's interesting to talk to him about it. He had to oversample the top
end, and that's how he was able to make the 28 kHz sound nice
and smooth. Otherwise, you know what top end sounds like with
digital, right? Kind of jagged. The first time I listened to the top end,
I was like, "Really? This is really good!".
I was expecting to stress out over it because of how digital plugins can be... but they got it, the curves were there, it's smooth. You
can really use it without regretting that you used it, you know? And
the software has some advantages, like the Mid/Side feature, and
you can use as many of them as you want...

What is the PA11 module on the plug-in-is that one of
your preamps we haven't heard about?

The PA11 is actually PSP's preamp design. The only thing they
took from me was the 6 dB boost at 28 kHz button from my MA5.

From here, I think we will leave the rest of the interview
to the plug-in guys. This has been really informative
and it was great talking to you.
OK, likewise, Paul.

algorithm designer of PSP E27) had to deal with lots of analog
phenomena. The other big challenge was the reconfigurable GUI.

Who decided to add the dual E27 / 6-band mode?

We came to this in a team, and also consulted with Avedis,
who was very supportive and open to the ideas on our feature list.

Avedis told me that the PA11 was your preamp design?

We knew we needed an extra analog input module for level
adjustment; we decided that a good idea would be to add a
highpass filter and controls for the E27's amplifier stages and
transformer emulation. Thus we allow the user to control the
amount and character of analog-like flavor that the plug-in
introduces. It's a subtle influence, because Avedis uses such
topnotch components which don't disturb the sound... we just
wanted to help to polish it.

You guys did a great job on this, and I know it will see
lots of use in my sessions!
Thanks, Paul. We are happy to have it in our collection.

RECORDING April 2017

Table of Contents for the Digital Edition of Recording - April 2017