Vacuumsound releases ADT – Artificial Double Tracking and RIAA – phono equalization

Vacuumsound ADT

Vacuumsound has released two freeware effect plug-ins for Windows and Mac: ADT – Artificial Double Tracking and RIAA – phono equalization.

ADT – Artificial Double Tracking

The ADT technique was developed at Abbey Road Studios by engineers recording the Beatles in the 1960s. To free John Lennon from having to sing everything twice for real double tracking they came up with an artificial replacement: they sent the original signal to another tape machine and re-recorded it. Due to the physical distance between record and playback heads the new signal was delayed. The length of the delay depends on the tape speed (the slower the tape is running the longer it takes for the signal to travel from the record to the playback head). However, due to the machine’s (small amounts of) Wow and Flutter the delay time was not fixed but varied slightly, giving an additional chorus-like effect.

The ADT Plug-In takes a mono input signal and creates a stereo output. The original input signal will be output on one channel the new ADT signal on the other. Blending the two is also possible. The Plug-In allows to control the delay time (10 – 50ms), Wow and Flutter (both with intensity in % and frequency). All values are based on the technical data of the tape machine that was originally used to create this effect.

RIAA – phono equalization

This Plug-In provides normal and inverse RIAA equalization. It thus can be used for record playback or vinyl cutting purposes. Another nice trick is to use it to simulate certain ‘vinyl sound effects’ by applying the inverse RIAA curve to your signal and after running it through a compressor converting it back to flat.

“RIAA – phono equalization” works at the standard sample rates from 44.1kHz up to 96kHz.

Both plug-ins are available for Windows and Mac (including 64-bit support, VST/AU). Donations are welcome.

Visit Vacuumsound for more information and links to download the plug-ins.

  • Ken Leonard

    I grabbed both downloads and have tried them.

    There is a problem, first of all, that the GUI is (technically speaking) busted–the “Save preset”, “Delete preset” and “OK do it now” button-positions are all overlaid by the “OK” button-image so it’s pretty blipping difficult to use them.

    Then there’s the little problem that the ADT thingie reads only the Left channel and drops its effect output in place of the Right channel–thus destroying my stereo project when it should (I think) read my choice of channel and drop the channel+effect back in place of that channel.

    Plus the problem that the level controls are slider-only, with no way to just enter the specific level I want.

    And, finally, the problem that mode controls that ought to be _some_ kind of on/off, yes/no, A/B switches are doggone sliders of uncertain effect, like on-bit-mid-more-most or some such arrangement.

    All in all, both are too much trouble to keep in the library.

  • Cheddar man

    Perhaps you didn’t read the specs for the adt plug-in? It stated, the input is for a mono signal.
    It takes a mono signal (not stereo!) and makes a pseudo stereo output.

    I don’t know many plug-ins (especially freeware) that offers a means to input exact amounts!

    Most Daws have a means to turn fx on or off. Does your Daw not have this feature?

  • Ken Leonard

    As I saaid, but maybe not too clearly, the problem is not that the ADT takes one-channel input but that it takes it _only_ from Left channel, with the second half of the problem being that it does not generate an ADTed new channel but clobbers my other stereo channel. At the least, if ADT produced a mixed output instead of two ouputs, I could do ADT on one channel at a time if I wanted to do stereo ADT.

    Yes, I can turn FX on or off, and even apply them to clips within a project.

  • Cheddar man

    Generally, the left channel is used with mono related plugins. Even hardware follows this convention. On my old Roland groove box; the outputs offer stereo and mono, with the mono choice being taken from the left channel when connecting it to a keyboard amp for example.

    The ADT is for mono only sources like a guitar or vocal and shouldn’t be used on the master buss or channel. I think you’re missing the point of this plugin. It’s for the purpose of making a mono source sound like it’s stereo. This means, you should only use it on mono only sources. I wouldn’t put this on anything but a vocal or guitar track which are mono related sources.

    Your stereo project is being smashed because the plug-in is mono. The 2nd channel it produces is nothing more than a delayed output.

  • Ake Zieden


    Is the ADT double tracking plugin compatible with the new Snow Leopard for Mac?

    Ake Ziedén, Sweden

  • Hi Ake,
    I have no idea as I don’t use Snow Leopard, but you could ask the developer. His email address is at the bottom of this page: