Freq Monster 801
FM synthesizer frontend for OPL3 compatible sound cards
Using Freq Monster 801 in Windows.
Table of contents
  1. Setup
  2. Setup (Port address)
  3. Setup (YMF262 plugin DLL)
  4. Midi
  5. kX Project FX
  6. kX Project LFO
  7. kX Project + Jesusonic
  8. kX Project + Reajs
1. Setup


  1. The sound card driver for your specific card. For example ForteMedia FM801 devices may use the Terratec 512i WDM driver in Windows XP. See the Drivers section for links to vendor websites with card specific drivers.
  2. GiveIO.SYS if you are running Windows NT/2000/XP, found here.
    This isn't needed for Windows 95 or 98 but is for NT derived systems such as XP. If you have trouble loading GiveIO.SYS at boot time then you may try installing it via Speedfan which also uses it.
  3. Freq Monster 801 from this site.

Run Freq Monster 801 and it will show a configuration panel.

A breakdown of the configuration is as follows.


  • Type - The type of hardware device or WAVE for the YMF262 plugin DLL.
  • Port address - This is the I/O base port address (hexadecimal) of the selected device.
  • Port delay - On some motherboards we need a delay between writing to I/O ports.

Wave device

  • No wave output - This is a placeholder, use the drop down list to select your PCM device here when using the YMF262 plugin DLL.
  • Sample rate - Number of stereo 16 bit samples per second. 11025 is reasonably good value.
  • Sample buffer size - Number of samples per buffer. Actual memory size is buffer size x 2 (stereo) x 2 (16 bit). Try 128 here.
  • Sample ring length - Number of sample buffers linked together in a ring. A good size to start with is 8.
  • No wave file output - This is a placeholder. When changed (via the ? button) we can specify a WAVE output file which will be written to contain the session. This file only becomes valid after closing Freq Monster 801 as it can only finalise the WAVE file on completion.

Wave callback

  • Thread - Wave playback uses a self contained thread to process the sample ring buffer.
  • Window - Wave playback uses the main window to process the sample ring buffer.

Midi callback

  • Function - Inbound midi events from external devices and applications arrive via a callback function (driver thread).
  • Window - Inbound midi events from external devices and applications arrive via the main window.

Optional features

  • Circuit bend - This enables the circuit bend module which adds a programmable method of malforming register and data access to the hardware or software device.
  • CC - This enables the Control change module which allows configurable CC messages to be mapped to synthesizer controls.
  • Keyboard - This enables a very simple keyboard module which is for auditioning patches and little else.
  • LFO - This enables the LFO (low freq. oscillator) module which combined with a clock source automates the sending of CC messages to synthesizer controls.
  • Sequence - This enables the simple Sequencer module. This modules takes an incoming key as a trigger and then automatically plays another note or sequence of notes.

Setup your device (see below for more information about port addresses) then enable any required optional features and click OK to open the main window.

Select a preset then play. In this example we have VMPK as a virtual midi keyboard, see the Midi section below for more information about this.

If the sound in unreliable, try different port delay parameters in Freq Monster 801 by restarting the application to reconfigure it.

Back to top
2. Setup (Port address)

In order to configure Freq Monster 801 it needs some information regarding the I/O port address of your sound card. See the following image where in Windows 98 we configure the address of an ALS4000 device in the Freq Monster 801 configuration panel.

To access the system properties dialog go to the control panel and select `System' (Nb. this example was made in Windows XP not Windows 98, but Windows 98 is similar).

From there select `Device Manager' on the `Hardware' tab.

And from within `Device Manager' determine which is your sound card and double click that entry. In the following example a ForteMedia FM801 device (Genius SM32X2) is shown.

When the property page for your device has opened select the `Resources' tab (as seen below) and read-out the `I/O Range' value. This range value is what is used to configure Freq Monster 801. In this example the ForteMedia FM801 device (Genuis SM32X2) has an I/O port address of 9000 (hex).

Back to top
3. Setup (YMF262 plugin DLL)


  • Freq Monster 801 from this site.
  • The YMF262 plugin DLL from here
    Place the file `ymf262.dll' in the directory where you extracted Freq Monster 801.

Run Freq Monster 801 and set the sythesizer type to WAVE, select your PCM wave output device and then use these values for the wave device configuration.

  • sample rate: 11025
  • sample buffer size: 128
  • sample ring length: 8

Enable any required optional features and click OK to open the main window.

Select a preset then open the keyboard applet on the main window by clicking 'Key' to test playback.

If the stream in unreliable, try different WAVE parameters in Freq Monster 801 by restarting the application to reconfigure it.

Back to top
4. Midi


  1. LoopBe1 at
    This works in both 32 bit and 64 bit Windows so is suitable for both hardware and software device setups.
  2. Virtual Midi Piano Keyboard (VMPK) from

Run Freq Monster 801.

  • Set the Freq Monster 801 midi input to `LoopBe Internal MIDI'

Run Virtual Midi Piano Keyboard (VMPK).

  • Set the VMPK midi output connection to `LoopBe Internal MIDI'

Select a preset then play.

Back to top
5. kX Project FX

Firstly obtain a kX compatible sound card. Go to to get more information.


  1. The sound card driver for your kX compatible card at site linked to above. I use kX 3550 on Windows XP which is the recommended version since later versions have issues with hardware detection and have broken plugins such as the decimator.
  2. ProFx for kX at
    This is to replace the older and also broken ProFx plugin shipped with the kX driver. Unzip the plugin and store it in the "C:\Program Files\kX Audio Driver" directory. Next, from the DSP window in kX, right click and select Registers Effects (Dane/Kxl...) and select the unzipped ProFx plugin to install it.


  • Route the audio out of your OPL3 compatible card into the Line-in of your kX card, alternatively should you have S/PDIF, route the digital out of your OPL3 compatible card into one of the digital inputs of your kX card. For example I currently route the S/PDIF output of an A-Trend YMF724 card into the S/PDIF input on an Audigy Platinum.

The configuration of the kX driver is quite complex and I won't go into great detail here, you are advised to study documentation elsewhere if any of my steps are difficult to follow and understand.


  • Right click on the kX tray panel icon to reveal its popup menu. From that menu select `kX DSP'.
  • On the kX DSP panel, right click and select `Clear DSP'.

This gives us blank slate to work on.

Now we will create an input.

  • If you are using S/PDIF, right click on the DSP panel and via `Add Effect/Plugin' locate ProFx:SRC and add it to the panel. Double click on SRC to assign the physical input, choose the correct digital input CD S/PDIF or Coax/Optical.
  • If you are using Line-in, right click in the DSP panel and via `Add Effect/Plugin' locate ProFx:ADC and add it to the panel. Double click on ADC to configure the physical input. You can use either the left (ADC) or right (UDA) devices. Deselect the left (ADC) and enable the right (UDA) and enable the Line-in.

Here is how it looks with both a SRC and ADC plugin added to the page.

Now we will create an output.

  • Right click on the DSP panel and via `Add Effect/Plugin' and locate ProFx:kXlt, add it to the page. This plugin can route audio to your Line-out, headphone jack, S/PDIF out and also to Windows multimedia for recording purposes.

The kXlt plugin renames itself dependant upon the sound card you have. k1lt for SBLIVE! and k2lt for Audigy.

To test your sound card you can connect the input directly to the output and play a sound through the device.

  • To create a patch cable left click on a plugin socket, then move the mouse to a target plugin socket and release the left mouse button.

Here we have done the above to connect the ProFx:SRC directly to the S/PDIF output.
If you now play something on that input it will travel through to kX card and appear at the output.

Now we will remove those test patch cables and add a mixer.

  • Right click on a plugin socket and select `Disconnect'. Do this for both our test patches.
  • Right click on the DSP panel and via `Add Effect/Plugin' add a ProFx:MX8 which is 8 stereo channel mixer.

The mixer plugin offers us two outputs, one for playback and one for recording. Each stereo input channel can be enabled for either of these, by default they are all enabled for playback and can be enabled for record by clicking the LED next to `R' for record. Each stereo input channel also has two sends, each send pair has a dedicated output and we can simply route the output from a send plugin back into one of the mixer inputs.

To finish off we will now add a DSP effect.

  • Right click on the DSP panel to add another plugin, this time named `Reverb Lite'.
  • Configure the DSP panel as per the image below (take your time).

Notice that we have adjusted the input levels and the send level to the reverb and also the reverb input level.

If you now play a sound through the kX card a reverb effect will be added to it using the DSP plugin `Reverb Lite'. Since this is a DSP effect no CPU use is required to perform this operation. You can adjust the reverb parameters by double clicking the plugin and moving its sliders.

Back to top
6. kX Project LFO

Perform the step outlined above for kX Project FX.

For demonstration purposes we will add a DSP filter insert to the DSP panel inline with our source input.

  • Right click on the panel and add the plugin `EQ & Filter : Phat EQ Stereo'.
  • Route your input through the filter (as shown below).

You may also patch your input into another mixer channel if you wish to create a dry input but this is beyond the scope of this simple example.

If you double click the Phat EQ plugin you will see that it has a number of parameters. For this LFO automation example we will be affecting the `Freq.(Hz)' parameter.

  • Right click on the kX tray panel icon to reveal its popup menu. From that menu select `kX Automation'.
  • Configure the automation, setting midi CC 71 as the input controller for the Phat EQ frequency.

We use midi CC 71 since Freq Monster 801 by default has 71 assigned to its auxiliary 1 output.

Now, to affect the frequency cut-off of the filter in real-time we need to configure an LFO in Freq Monster 801.

  • Open the Freq Monster 801 LFO window and configure the Auxiliary midi device to be `kX control'.
  • Configure an LFO ensuring that the send goes to Auxiliary 1.
  • Enable the LFO panel and the LFO itself.

In this example we send a saw wave ramp to the auxiliary device.

Selecting the multimedia timer in the clock window and then clicking start will automate the filter cut-off frequency in Phat EQ.

Back to top
7. kX Project + Jesusonic

Perform the step outlined above for kX Project LFO.


  1. Jesusonic at
    We will be using the loopsampler-m2 plugin in Jesusonic.
  2. Wavosaur from This is to record our performance. You don't need this if you have no intention of recording anything.

Run Jesusonic and it will present you with its configuration panel.

  • Configure Jesusonic I/O to utilise the kX ASIO driver.
  • Then configure Jesusonic to use kX in 2/3 for input and kX out 2/3 for output and click OK.

We are using kX 2/3 ASIO here since 0/1 will be utilised for WinMM recording in Wavosaur.

You will now be presented with a blank page in Jesusonic where it requests that you add a plugin using the 'A' key.

  • Press 'A' in Jesusonic and locate and add the loopsampler-m2 plugin.

The loop sampler plugin can't be used just yet though, first we will setup Wavosaur then the DSP.

Run wavosaur.

  • From the Options menu choose the audio configuration ensure its set as below, click OK.
  • From the tools menu you can select `Monitor input' to monitor the wave input.
  • Press the record icon at any time to wish to record.
  • If you want to hear the the playback from Wavosaur you will also need to add a ProFx:SRC for kX 0/1 to the DSP panel. This is left as exercise and not covered here.

As you can see we are recording from kX Wave 0/1 which is the WinMM wave recording device.

Now we will configure the DSP. This is much like the configuration before except a bit more complex.

  • Add a ProFx:ASIO plugin. Here we route the output of our previous configuration into kX ASIO 2/3.
  • Add another ProFx mixer, this time ProFx:MX6. In this mixer we have as input a ProFx:SRC (renamed to FxBus 2/3) from kX bus 2/3 which is our Jesusonic output and also add the output of the MX8 mixer (Freq Monster 801).
  • Patch the output configuration to use the MX6. We send the record output of MX6 to WinMM which will be recorded by Wavosaur.

What we are doing here is taking the output of Freq Monster 801 (plus any insert or send effects) and sending it to Jesusonic. We then take the output of Jesusonic and mix it with Freq Monster 801 then send the final product to WinMM for recording in Wavosaur.

Now we can get back to playing around with Jesusonic.

  • Press '1' to start the loopsampler-m2 recording.
  • Play some notes on your keyboard.
    What you play should now be recorded in Jesusonic.
  • Press '1' again in loopsampler-m2, it should now say `playing looped+recording'.
  • Keep playing notes. We now have home-made Psychic TV.

If you don't hear anything check the DSP settings and routing and try again.
If you want to record your session, don't forget to click the record icon in Wavosaur.

Back to top
7. kX Project + Reajs

Perform the step outlined above for kX Project + Jesusonic.


  1. Reajs (part of Reaplugs) from
  2. Download and extract savihost from

Reaplugs will install into C:\Program Files\VSTPlugins\ReaPlugs or in my case the drive path is D:\

  • Copy the savihost.exe extracted above into the ReaPlugs directory and rename it to `reajs.exe'.

Run readjs.exe.

Above we have opened the menu item Devices/Wave to begin configuration.

  • In the Device/Wave menu item select kX ASIO as the output port then click OK.

That sets up the wave driver configuration, now we need to route the audio in.

  • Go to the menu item Engine/Configure.
  • Set the input channel assignments to kX In 2/3.

Clicking those three dots `...' allows selection of the device input.

Now we route the audio out.

  • Go to the menu item Engine/Configure.
  • Set the output channel assignments to kX Out 2/3.

As before the three dots allow selection of the device outputs.

You can now run the loopsampler-m2 or any other plugin by pressing `Load' and finding it on the popup menu.

Other Reajs plugins can be found on the net, for example at

Alternatively, to savihost, you can use vsthost (from the same site) to allow greater control of VST plugins found in Reaplugs.

Back to top