O NTRAC K
Convoluting Reverb! Pt. 2
Last month we talked about convolution
reverbs and the technology behind them.
This month, let’s take a look at a unique
product called Speakerphone, which, among
other things, is an impulse response-based
speaker emulator. Whether or not you use
software to explore guitar sounds, it’s worth
opening your ears up to the possibilities this
kind of product can offer you.
Designed by the crew at Audio Ease (
creators of Altiverb), it may seem a bit overwhelming at first. Speakerphone has several
functions: it has samples of hundreds of original speakers; it offers distortion, tremolo,
delay, EQ and dynamics; it has bit crushing
and sample rate reduction; a radio receiver
tuning dial; GSM cell phone data compression; and a library of samples – in addition to
a full-blown convolution reverb.
A screenshot of Speakerphone
While a big part of this program is perfect
for post-production (like making your voice
go through a cell phone in a train station),
it’s the classic amp speakers that PG readers will really dig. In order to capture the
impulse responses of speakers from great
guitar amps, you have to find them. Working
with Clubhouse Studios in Rhinebeck, New
York, they sampled some serious amps from
their collection. How about plugging into a
1952 Fender Deluxe, ‘ 57 Fender Super Amp,
‘ 58 Gibson GA- 6, 1960 Maestro Reverb-Echo, ‘ 63 Vox AC30 Top Boost, ‘ 65 Fender
Princeton, ‘ 66 Sears Silvertone or a ‘ 66
Ampeg B- 18?
Speakerphone is different from typical guitar
modeling plug-ins since the amps were literally captured at two mic positions with an
impulse response tone. You don’t turn knobs
on the selected amp to tweak the sound – if
you want more treble or bass, use the separate EQ section. Remember, this is a speaker
emulator with environments – kind of like a
suite of tools to pick and choose from.
Once installed – consisting of about 4GB of
samples, which can be placed on a separate
drive – it’s inserted like a plug-in on an audio
track. It runs as an RTAS, MAS, VST or AU
(Audio Units) plug-in and a great place to
start is by listening to presets. In the “guitar
fx” category you can choose from things like
“Billy Solo” – a ‘ 51 Gibson GA- 20 in a live
bedroom – or my favorite, “Hangover Blues”
– a ‘ 52 Fender Deluxe in a tiled bathroom.
From there, it’s easy to get the hang of
how it works and create your own favorites.
Try adding a little analog distortion, dropping the low-end out with EQ and adding
a tremolo or phaser in the “mod” section.
As you would expect, some amp models
and effects sound better than others, but it
certainly depends on what your need is for a
To select a guitar amp, simply click on the
Guitar/Amp icon. From there, a dropdown
menu appears showing all the sampled amps
and the selected mic position. The tone will
change with different mic choices and you
have to run through each to hear its result.
The amp you’ve selected will then appear
midscreen in the speaker module box.
You can then choose the self-explanatory
“Pre-Speaker Before FX” or “Post-Speaker
After FX” for tone shaping. Also, by selecting “more info,” an expanded photo of the
amp will appear with any relevant information. While I did get a kick out of checking
out the pictures, it’s the sound that we’ve all
come here for. It’s a nice touch that you can
easily click through the different amps while
the track plays, instantly hearing each one on
As with any modeled amp plug-in, there’s
some latency to deal with. To get the exact
specs, I emailed the folks at Altiverb and
found out the following:
“With Live throughput (listening to the
plug-in while playing) total latency is twice
the hardware’s buffer size plus a couple of
samples ( 50 to 200, depending on the hardware interface). So if you set hardware buffer
size to, say 128, you are looking at a latency
of 256 + say 100 = 356 samples. In the latest release we have had to add a popup to
set the internal buffer size of Speakerphone
because the hardware buffer size cannot
be determined by a plug-in in Logic. But in
other hosts, toning down the hardware buffer size is all you need to do to get you in a
So if the latency bothers you, just try it out
on tracks you’ve already recorded.
In addition to the amps, there’s a huge selection of oddball speakers. Want to hear your
guitar through a classic Mac SE computer?
How about a Marshall Mini, Sony tape deck
speaker, a 1962 transistor radio or a solid-state walkie-talkie? While it may sound silly,
I got some amazing sounds by just flipping
through the presets and experimenting.
Overall, it’s a highly creative tool and its
applications extend far beyond the guitar.
Speakerphone simply offers up tones that I
couldn’t achieve any other way, aside of owning a particular amp – or walkie-talkie.
is a producer, engineer and mixer who has worked with
artists ranging from Al DiMeola to David Bowie. A lifelong guitarist, he’s also the author of Pro Tools Surround
Sound Mixing and composes for such networks as
Discovery Channel, Nickelodeon and National Geographic.