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<div class=Section1>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>For the math of frequency shifters, you
just need a bit of trigonometry and a smattering of algebra. You need these
for most audio electronics, actually. I am one of those old-school types who
believes that trig and algebra are within the purview of everyone, even those
who attended art school. Transfer functions require some calculus and Laplace/Fourier
transforms, and that is really the subject matter of an electronic engineering
education (although all process engineers learn <st1:place w:st="on">Laplace</st1:place>
transforms for the purposes of designing control networks, e.g., for automatic
control of chemical plants).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<div>
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face="Times New Roman"><span style='font-size:12.0pt'>
<hr size=2 width="100%" align=center tabindex=-1>
</span></font></div>
<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'> ColinMuirDorward
[mailto:colindorward@gmail.com] <br>
<b><span style='font-weight:bold'>Sent:</span></b> Wednesday, March 11, 2020
12:06 PM<br>
<b><span style='font-weight:bold'>To:</span></b> David G Dixon<br>
<b><span style='font-weight:bold'>Cc:</span></b> Tom Bugs; *SYNTH DIY<br>
<b><span style='font-weight:bold'>Subject:</span></b> Re: [sdiy] frequency
shifter</span></font><o:p></o:p></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Ok, I see now why I've never heard of this dome filter aka phase shift
network, because it's patented/protected material. <o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Tom, do you have any audio clips to share?<o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Re the maths, what's the quickest route to get there? I just wrapped up
ten years of art school, maybe it's time I got a real education now.<o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>C<o:p></o:p></span></font></p>
</div>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>On Wed, Mar 11, 2020 at 4:44 PM David G <st1:City w:st="on"><st1:place
w:st="on">Dixon</st1:place></st1:City> <<a href="mailto:dixon@mail.ubc.ca">dixon@mail.ubc.ca</a>>
wrote:<o:p></o:p></span></font></p>
</div>
<blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;
margin-left:4.8pt;margin-right:0in'>
<div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'>I’d be lost without the maths. I always derive the transfer
functions of any filters I design, for example, and I have found that to be
invaluable.</span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'> </span></font><o:p></o:p></p>
<div>
<div class=MsoNormal align=center style='text-align:center'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'>
<hr size=2 width="100%" align=center>
</span></font></div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><font
size=2 face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma;font-weight:
bold'>From:</span></font></b><font size=2 face=Tahoma><span style='font-size:
10.0pt;font-family:Tahoma'> Synth-diy [mailto:<a
href="mailto:synth-diy-bounces@synth-diy.org" target="_blank">synth-diy-bounces@synth-diy.org</a>]
<b><span style='font-weight:bold'>On Behalf Of </span></b>Tom Bugs<br>
<b><span style='font-weight:bold'>Sent:</span></b> Wednesday, March 11, 2020
12:49 PM<br>
<b><span style='font-weight:bold'>To:</span></b> *SYNTH DIY<br>
<b><span style='font-weight:bold'>Subject:</span></b> Re: [sdiy] frequency
shifter</span></font><o:p></o:p></p>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<p><font size=3 face="Times New Roman"><span style='font-size:12.0pt'>Don't
feel you *have* to get tangled up in maths - I could do maths up through my
technical university course, but frankly it never conveyed spirit to me & I
rarely go anywhere deep with it in any of my designing.<br>
I was also going to suggest looking up the CGS Dome Filter (the phase shift
network mentioned) but don't think schematics were presented - it does, however,
state the Electronotes article I referred to - #83<br>
<a href="https://sdiy.info/wiki/CGS_dome_filter" target="_blank">https://sdiy.info/wiki/CGS_dome_filter</a><o:p></o:p></span></font></p>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>On 11/03/2020
15:22, ColinMuirDorward wrote:<o:p></o:p></span></font></p>
</div>
<blockquote style='margin-top:5.0pt;margin-bottom:5.0pt' type=cite>
<div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>I'm still working
on these replies, folks, thanks for the discussion! <o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>OK, TBH, I'm
pretty lost. It's probably beyond me without having the math. Is it anything
like barber-poling a series of APF filters?<o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
</div>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>On Wed, Mar 11,
2020 at 9:43 AM Quincas Moreira <<a href="mailto:quincas@gmail.com"
target="_blank">quincas@gmail.com</a>> wrote:<o:p></o:p></span></font></p>
</div>
<blockquote style='border:none;border-left:solid windowtext 1.0pt;padding:0in 0in 0in 6.0pt;
margin-left:4.8pt;margin-top:5.0pt;margin-right:0in;margin-bottom:5.0pt;
border-color:currentcolor currentcolor currentcolor rgb(204,204,204)'>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>This is a
celebrated one, by JHaible. I have the pcb, waiting for the day when i’ll have
time to source the parts... <o:p></o:p></span></font></p>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'><a
href="http://jhaible.com/legacy/frequency_shifter_fs1a/fs1a" target="_blank">http://jhaible.com/legacy/frequency_shifter_fs1a/fs1a</a><o:p></o:p></span></font></p>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>Sent from my
iPhone<o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>On 11 Mar 2020, at
4:11, Tom Bugs <<a href="mailto:admin@bugbrand.co.uk" target="_blank">admin@bugbrand.co.uk</a>>
wrote:<o:p></o:p></span></font></p>
</div>
<blockquote style='margin-top:5.0pt;margin-bottom:5.0pt' type=cite>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<p><font size=3 face="Times New Roman"><span style='font-size:12.0pt'>My brain is
not awake enough to closely follow Dave's description! But I remember there's a
good basis in an old Electronotes - I didn't follow it exactly by any stretch
but it really helped me design my own, the theory I took being:<br>
1) make a quadrature sine/cosine VCO<br>
2) audio input splits to two 6-stage all-pass filter<br>
3) each filter-chain is followed by a RingMod/Multiplier with the modulating
input coming one from sine / one from cosine<br>
4) then you do sum & difference of the two ring mods to get up & down
shifts.<o:p></o:p></span></font></p>
<p><font size=3 face="Times New Roman"><span style='font-size:12.0pt'>What I
really enjoyed was adding feedback! In fact, redeveloping the ideas at the
moment & adding in a bit of extra control + output mixing/panning. Really
great audio processor, even at LFO rates where it becomes a wonderful phaser
type machine.<o:p></o:p></span></font></p>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>On 11/03/2020
07:28, David G Dixon wrote:<o:p></o:p></span></font></p>
</div>
<blockquote style='margin-top:5.0pt;margin-bottom:5.0pt' type=cite>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'>I built a frequency shifter following the Bode plan. This is
frequency shifting by manifesting certain trigonometric product-to-sum formulae
using electronic circuits:</span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'> </span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span lang=PT-BR style='font-size:10.0pt;
font-family:Arial;color:navy'>sin u sin v = 0.5 [cos(u – v) – cos (u + v)]</span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span lang=PT-BR style='font-size:10.0pt;
font-family:Arial;color:navy'> </span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span lang=PT-BR style='font-size:10.0pt;
font-family:Arial;color:navy'>cos u cos v = 0.5 [cos(u – v) + cos (u + v)]</span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span lang=PT-BR style='font-size:10.0pt;
font-family:Arial;color:navy'> </span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'>So, if you have two signals with their 90-degree quadrature signals
(say, u is the audio you want to shift and v is the on-board quadrature
oscillator), then if you multiply the signals together (using a four-quadrant
multiplier) and also multiply their quadrature signals together (using a second
four-quadrant multiplier) then you can sum the multiplier outputs together, and
you will get the following (by adding the two equations together):</span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'> </span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'>cos (u – v)</span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'> </span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'>This represents the audio signal u which has been frequency-shifted
downward by the frequency of the oscillator signal v. Of course, the
audio signal probably has many frequencies u occurring simultaneously, and they
will all be shifted down by v. That’s what makes frequency shifting sound
so alien and weird.</span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'> </span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'>By being clever with the summations of the multiplier output
signals (based on a little bit of algebra), you can also recover the up-shifted
audio:</span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'> </span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'>cos (u + v) </span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'> </span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'>With both the down- and up-shifted signals, you can get a stereo
effect.</span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'> </span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'>The entire circuit consists of a 90-degree phase displacement
network to generate the cosine of the incoming audio (I designed mine with 12
stages from 15 Hz to 15 kHz using a little thing I found on the internet called
QuadNet), a quadrature oscillator to generate both sine and cosine waves at
frequency v (mine is TZFM and consists of two Rubicon cores with sine shapers,
with one syncing the other in such a way that the two are always 90 degrees out
of phase), two four-quadrant multipliers (I built a dual unit from a single
2164 chip – two linearized VCAs), and a couple of output amplifier stages for
doing the summing. The key to success is to AC couple the signals into
the multipliers to eliminate DC offsets in the incoming signal, which is the
single largest source of error in the circuit. If that is done properly,
the multipliers require no trimming (if accurate summing resistors are chosen).</span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'> </span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'>The circuit works great and sounds super freaky. I’m
going to be building another one for one of our members here shortly.</span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'> </span></font><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=2 color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:navy'> </span></font><o:p></o:p></p>
<div>
<div class=MsoNormal align=center style='text-align:center'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'>
<hr size=2 width="100%" align=center>
</span></font></div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><font
size=2 face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma;font-weight:
bold'>From:</span></font></b><font size=2 face=Tahoma><span style='font-size:
10.0pt;font-family:Tahoma'> Synth-diy [<a
href="mailto:synth-diy-bounces@synth-diy.org" target="_blank">mailto:synth-diy-bounces@synth-diy.org</a>]
<b><span style='font-weight:bold'>On Behalf Of </span></b>ColinMuirDorward<br>
<b><span style='font-weight:bold'>Sent:</span></b> Tuesday, March 10, 2020 7:01
PM<br>
<b><span style='font-weight:bold'>To:</span></b> *SYNTH DIY<br>
<b><span style='font-weight:bold'>Subject:</span></b> [sdiy] frequency shifter</span></font><o:p></o:p></p>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face=Times><span style='font-size:12.0pt;font-family:Times'> </span></font><o:p></o:p></p>
<div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>Hi, I got a little
lost trying to understand what a frequency shifter is. I mean the pre-digital
method used by Moog (I think?).<o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>I recently built a
4pole APF, and was really impressed with some of the pitching effects I could
achieve with it. I'm guessing this is an entirely different method than the
frequency shifters like Moog and JH have done.<o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>Is the APF method
used by anyone? What are its limitations, and what is it even doing? <o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>Well, I guess I'm
just looking for some conversation on the topic of analog frequency/pitch
shifting methods. If anyone has any thoughts/experience they'd like to share.<o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>Cheers,<o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>Colin<o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'><br>
-- <o:p></o:p></span></font></p>
<div>
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<div>
<div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New"><span style='font-size:12.0pt;font-family:"Times New"'><a
href="https://www.instagram.com/colinmuirdorward/" target="_blank">https://www.instagram.com/colinmuirdorward/</a></span></font><o:p></o:p></p>
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<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New"><span style='font-size:12.0pt;font-family:"Times New"'><a
href="https://www.instagram.com/colinmuirdorward/" target="_blank">-<br>
</a></span></font><o:p></o:p></p>
</div>
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<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New"><span style='font-size:12.0pt;font-family:"Times New"'><a
href="https://www.instagram.com/ssdp_synthesis/" target="_blank">https://www.instagram.com/ssdp_synthesis/</a></span></font><o:p></o:p></p>
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<p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'><o:p> </o:p></span></font></p>
<pre><font size=2 face="Courier New"><span style='font-size:10.0pt'><fieldset></fieldset>_______________________________________________<o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>Synth-diy mailing list<o:p></o:p></span></font></pre><pre><font
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<pre cols=72><font size=2 face="Courier New"><span style='font-size:10.0pt'>-- <o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>BugBrand LTD<o:p></o:p></span></font></pre><pre><st1:country-region
w:st="on"><st1:place w:st="on"><font size=2 face="Courier New"><span
style='font-size:10.0pt'>UK</span></font></st1:place></st1:country-region> company No. 07199808<o:p></o:p></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>VAT No. GB 988 2629 57<o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>1 Ninetree Hill<o:p></o:p></span></font></pre><pre><st1:City
w:st="on"><st1:place w:st="on"><font size=2 face="Courier New"><span
style='font-size:10.0pt'>BRISTOL</span></font></st1:place></st1:City> BS1 3SB<o:p></o:p></pre><pre><st1:country-region
w:st="on"><st1:place w:st="on"><font size=2 face="Courier New"><span
style='font-size:10.0pt'>United Kingdom</span></font></st1:place></st1:country-region><o:p></o:p></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'><a
href="http://www.bugbrand.co.uk" target="_blank">www.bugbrand.co.uk</a><o:p></o:p></span></font></pre>
<div
id="gmail-m_9002857741622969805gmail-m_3126639033867629156DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2">
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size=3 face="Times New Roman"><span style='font-size:12.0pt'> <o:p></o:p></span></font></p>
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<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
line-height:13.5pt'><font size=2 color="#41424e" face=Arial><span
style='font-size:10.0pt;font-family:Arial;color:#41424E'>Virus-free. <a
href="http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient"
target="_blank"><font color="#4453ea"><span style='color:#4453EA'>www.avg.com</span></font></a>
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<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'><a
href="#m_9002857741622969805_m_312663903386762" width=1 height=1></a><o:p></o:p></span></font></p>
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<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>_______________________________________________<br>
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<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'>_______________________________________________<br>
Synth-diy mailing list<br>
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<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'><br clear=all>
<br>
-- <o:p></o:p></span></font></p>
<div>
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<div>
<div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'><a
href="https://www.instagram.com/colinmuirdorward/" target="_blank">https://www.instagram.com/colinmuirdorward/</a><o:p></o:p></span></font></p>
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size=3 face="Times New Roman"><span style='font-size:12.0pt'><a
href="https://www.instagram.com/colinmuirdorward/" target="_blank">-<br>
</a><o:p></o:p></span></font></p>
</div>
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<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><font
size=3 face="Times New Roman"><span style='font-size:12.0pt'><a
href="https://www.instagram.com/ssdp_synthesis/" target="_blank">https://www.instagram.com/ssdp_synthesis/</a><o:p></o:p></span></font></p>
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</div>
</div>
</div>
</blockquote>
<pre cols=72><font size=2 face="Courier New"><span style='font-size:10.0pt'>-- <o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>BugBrand LTD<o:p></o:p></span></font></pre><pre><st1:country-region
w:st="on"><st1:place w:st="on"><font size=2 face="Courier New"><span
style='font-size:10.0pt'>UK</span></font></st1:place></st1:country-region> company No. 07199808<o:p></o:p></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>VAT No. GB 988 2629 57<o:p></o:p></span></font></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'>1 Ninetree Hill<o:p></o:p></span></font></pre><pre><st1:City
w:st="on"><st1:place w:st="on"><font size=2 face="Courier New"><span
style='font-size:10.0pt'>BRISTOL</span></font></st1:place></st1:City> BS1 3SB<o:p></o:p></pre><pre><st1:country-region
w:st="on"><st1:place w:st="on"><font size=2 face="Courier New"><span
style='font-size:10.0pt'>United Kingdom</span></font></st1:place></st1:country-region><o:p></o:p></pre><pre><font
size=2 face="Courier New"><span style='font-size:10.0pt'><a
href="http://www.bugbrand.co.uk" target="_blank">www.bugbrand.co.uk</a><o:p></o:p></span></font></pre></div>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>_______________________________________________<br>
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</blockquote>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><br clear=all>
<br>
-- <o:p></o:p></span></font></p>
<div>
<div>
<div>
<div>
<div>
<div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><a href="https://www.instagram.com/colinmuirdorward/" target="_blank">https://www.instagram.com/colinmuirdorward/</a><o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><a href="https://www.instagram.com/colinmuirdorward/" target="_blank">-<br>
</a><o:p></o:p></span></font></p>
</div>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><a href="https://www.instagram.com/ssdp_synthesis/" target="_blank">https://www.instagram.com/ssdp_synthesis/</a><o:p></o:p></span></font></p>
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