These days we are witnessing a true renaissance of convolution reverbs. Processing power of personal computers has grown to the level where a convolution reverb plug-in running on a digital audio workstation (DAW) is no longer causing severe CPU overloads and audio dropouts. That is why many companies working in the field of pro audio solutions started to offer various products based on convolution processing.

Voxengo also offers its own convolution processing product. Pristine Space is a native PC VST plug-in which allows you to use convolution reverb impulses in your audio projects.

Pristine Space was mainly created for impulse reverb perfectionists: it does not implement various `combo' approaches which try to save CPU cycles by creating a synthetic reverb tail instead of performing a full convolution. Because such approaches in many cases give unsatisfactory results if you expect them to sound exactly like your original reverb impulse sounds, we have decided not to use them. Instead, we have optimized to the maximum both the efficiency of convolution processing and the plug-in's latency.

Pristine Space is a 8-channel convolution processor. Each channel is independent of the others, making it possible to use Pristine Space in various surround configurations. It also allows the user to apply a `true stereo' kind of processing, where each stereo channel uses its own reverb impulse (requiring 4 convolution channels in total). Sound designers and the like may find Pristine Space's serial convolution processing feature (which allows one to process the sound with several impulses in sequence) useful.

While Pristine Space does not offer various radical impulse transformation features, it still offers several very useful envelope-driven non-destructive impulse editing options, including volume, stereo width, stereo pan, low-pass and high-pass filtering, and a linear-phase equalization. You can also reverse, cut and time offset the loaded impulse file with ease, non-destructively.

By the way, Pristine Space can work with a latency as low as 64 samples (1.5 ms at 44.1kHz), making it possible to use it during tracking.

Pristine Space features:

The user interface of Pristine Space is divided into two major parts: a) the part below the "File..." button resembling a set of controls for 8 convolution channels and a set of main controls; b) the part above the "File..." button, including this button. This latter part consists of the file slot selector, the file selector, the envelope display and a set of impulse file adjustment controls with several knobs (e.g. "Delay", "Gain") and two switches ("REVRS", "A-GAIN"). Above the envelope display, you can see the information about the loaded impulse file: its title, copyright and the name of the engineer who created this impulse file. Please note the "Status" label: there you can see the status of the loaded file. In the case of an impulse loading error, you will be able to see what kind of error occurred.

Pristine Space is a 8-channel convolution plug-in with extensive routing capabilities. You can process any input channel with any loaded impulse response file and route the result into any of the output channels. Convolution channels themselves can be inputs to other convolution channels making serial convolution processing possible.

A general sequence of steps you should perform to get Pristine Space working is:

Alternatively, you can use one of the template factory presets or use the default preset to simplify the process of configuring the routing.

Please note that Pristine Space will automatically resample the loaded impulse if its sample-rate differs from the host output sample-rate. However, please note that resampling requires additional impulse loading time. For best results it is suggested that impulse response files be resampled with a dedicated sample rate conversion utility. Note that if sample rate conversion took place an asterisk will appear next to the sample rate number on the Status line.

Pristine Space supports wave files of any length. Be cautious when loading very large files because this can quickly overload the CPU.

You can use the "Preset..." menu button to perform basic FXP/FXB preset/bank management tasks. The "Set as default" menu option of the "Presets..." menu allows you to assign the currently loaded program to the default preset program. This default program will be loaded whenever you enable a new instance of the plug-in or reset the current program. You can use the "Reset default" option to restore the default factory preset.

By pressing the "A|B" button, you can exchange the current and shadow (or, alternatively, "A" and "B") programs. The "Copy" button copies the current program to a shadow one.

Since only a single shadow program is used for the whole program bank, you can use "A|B" button to copy programs. To do so, you first need to switch to a program you want to copy and press the "Copy" button. Next, switch to a program where you want to put the first program and press the "A|B" button.

The "Reset" button can be used to reset the current program. All parameters will return to their default states.

This is the file slot selector coupled with the envelope enable switch array. All slots have different colors which are used for `color-coding'. Buttons associated with a convolution channel will have the same color as the file slot this convolution channel uses. The same applies to the file selector controls. Their color reflects the currently selected slot.

The envelope enable switch array reflects the enabled/disabled state of the envelope of the currently selected slot. In order to edit or modify the loaded impulse response file, an envelope must be enabled. Note that the edits made by the envelopes are non-destructive since they don't make any actual changes to the impulse response file itself.

You may additionally select which impulse response channel is displayed by using the "Show Chn" selector.

"Show Mode" selector specifies which stage of the impulse response should be shown - unaffected ("Dry") or affected ("Wet") by the envelopes.

Right in the center you can find the file selector controls. You can use these controls to load the desired impulse response for the currently selected file slot.

The "File..." button allows you to select any WAV file located on your harddisk.

The "X" button unloads any currently loaded file.

You can use the left arrow and the right arrow buttons to quickly scroll through the file list.

The long button with the file name of the loaded impulse printed on it is actually a selector button. You can hold it to quick-select any file from the same folder where the currently loaded file is located.

To change a knob control's value, drag it with the left mouse button and move it up or down. For finer adjustment, press the right mouse button while dragging. Double-clicking on the knob with the left mouse button will return the knob to its default position.

On this picture you can see the controls of the convolution channel 1. All convolution channels are equal in functionality.

The "Flow" button displays convolution channel's signal flow diagram. Press this button again to hide the diagram.

The button on the right, with "4" printed on it, selects the number of enabled convolution channels. All disabled channels become `transparent' and thus cannot be used or adjusted.

Coupled "Slot/Chn" selectors are used to tell which impulse response file slot this convolution channel should use. Since the loaded impulse response file can be either a mono, a stereo or a multi-channel file, you have the option of choosing which impulse response file's channel (Chn) you wish to assign to this convolution channel. If the selected file channel is not available, the highest one which is actually available will be used. If the selected file slot has no impulse file loaded in it, the convolution channel will work in a bypass mode, with the wet signal output disabled. NOTE: Each convolution channel is able to use only a SINGLE channel from any impulse response slot meaning that if the impulse file you have loaded has more than one channel you should utilize more than one convolution channel also.

The "Aud In" selector specifies which audio input channel (host's IN channel) is used by this convolution channel as an input (this audio channel will be also fed to the output directly, multiplied by the Dry parameter value). You can select "---" to disable processing of this convolution channel. You can also specify any of the previous convolution channels (CONV) as an input. NOTE: Serial convolution processing does not allow a host to compensate for additional processing delay imposed by serial processing. It is suggested that you use serial processing with lower plug-in latencies only.

The "Aud Out" selector specifies which audio output channel (host's OUT channel) the convolution result is routed to. Please note that "---" state does not disable the actual processing of the convolution channel (given the other parameters allow it).

The "Dry" and the "Wet" knobs allow you to control the balance between the dry and the wet signal on the output stage. Please note if the "Aud Out" is equal to "---", these knobs will be shadowed.

The "Quality" switch selects the quality mode of the convolution channel. The "Low" quality is usually 1.5 to 2 times more efficient. It can be pretty useful during tracking and mixing. However, it is suggested to enable the "Max" quality mode when rendering a final mix.

Using the "S" (solo) and the "M" (mute) switches, you can solo and mute the convolution channel, respectively.

The "Link To" selector allows you to link a convolution channel to any other convolution channel. The Solo and Mute switches and the Quality setting will be linked, and thus will be disabled. The Dry and Wet knobs, instead of being absolute values, will be values relative to the values specified in the "Link To" channel (the dB labels below these knobs will be highlighted with a right-arrow to denote relative values in effect). This allows you to simplify control over the linked convolution channels.

NOTE: If you think you have correctly specified all of these parameters, but are still not hearing any sound, make sure the chosen slot has an impulse file loaded in it and the selected input and output channels are actually available in the current configuration. Also, check the state of the "M" and the "S" switches.

These are the main output controls.

The "Dry" (upper) and the "Wet" (lower) knobs adjust the dry and the wet gain value of all convolution channels, respectively.

The button with the "Default" label printed on it allows you to override the quality settings of all convolution channels. This can be useful to quickly switch between the low and the max quality setting in all convolution channels. In the "Default" state, quality settings would not be forced to some particular state, but instead each convolution channel will use its own quality setting.

The "Mute D" and "Mute W" switches allow you to switch dry and wet signals, respectively, in all convolution channels, on and off.

Please note the three labels on top of this picture. The label with the numeric value (64) displays the processing delay (latency) the plug-in is currently using.

The "INs" label shows the number of inputs currently available. For example, if there are 2 inputs currently available you can only use "IN 1" and "IN 2" Aud In channels as a convolution channel's inputs. Pretty much the same applies to the "OUTs" label. This label shows the number of outputs currently available. The number of inputs and outputs currently available can be adjusted on the global settings screen.

This is a set of controls which allows you to adjust the loaded impulse response file non-destructively. It reflects the state of the impulse response loaded in the currently selected slot.

Using the "Offset" and the "Length" knobs you can cut the loaded impulse response file. You can monitor the effect of these knobs on the envelope display.

The "Delay" knob adjusts the output delay of the impulse response.

The "Gain" knob adjusts the volume of the impulse response.

The "A-Gain" (auto gain) switch enables/disables the automatic gain function. Enabling auto gain is generally useful because it keeps the volume of all impulses equal so you can load different impulse response files without needing to continuously adjust the "Gain" knob. Even with the "A-Gain" switch enabled, you can still adjust the output gain with the "Gain" knob.

The "Revrs" (reverse) switch enables/disables the reversal of the loaded impulse response file.

You can use the "Link To" selector to link the Offset and Delay controls of the currently selected slot to another slot. Please note that if these controls were linked you will have no control over them, in the current slot. Linked slot also uses another slot's internal auto gain value. Linking is useful when you use split-channel impulses which are loaded in different slots.

The "+" switch additionally enables Length and Gain controls linking when the Link To selector is used.

Here you can see the envelope editing part of the user interface. It reflects the state of the impulse response loaded in the currently selected file slot. In the center there is a wave display of the impulse response. It displays peak values only. The envelope (blue-colored curve) is shown on the wave display, overlayed.

The selectors with the "V", "S", "P", "L", "H" and "E" letters are the envelope selectors. "V" stands for "Volume", "S" stands for "Stereo Width", "P" stands for "Stereo Pan", "L" stands for "Low-Pass", "H" stands for "High-Pass" and "E" stands for the equalizer envelope.

The scale on the left denotes the relative power of the impulse response in dB. You can view the wave with the resolution of up to 80 dB. The meaning of the scale on the right depends on the currently selected envelope. The scale below the wave display shows impulse response time, defined in seconds.

When the equalizer envelope is enabled, both the left and right scales show the equalizer gain, in dB, and the scale below the wave display shows frequencies (logarithmic scale).

In the top right corner of the wave display, you can see the mouse position readout.

The "Link To" selector allows you to link the currently selected envelope of the currently selected file slot to the same envelope of another file slot. Such linking works as a substitution. Linking can be useful if you wish to edit the envelope in one slot without the need to duplicate your modifications in another slot.

The "Copy" (copy to) button allows you to copy the current envelope of the current file slot to the same envelope in another file slot.

The "Reset" button resets the envelope.

The "Apply" button is available only if the "Auto Apply" mode is off and the envelope has been changed. You can press this button to apply all changes made to the envelope.

This picture shows the control points which can be dragged with the left mouse button to adjust the current envelope. Double-clicking on a control point removes it. The first and last points return to default vertical position when double-clicked. To add a new control point, double-click the control surface at the desired position.

If several points are selected and you double-click any of the existing points, all selected points will be either deleted or reset.

Dragging the envelope line selects two points, adjacent to this line, and enables you to move these points, vertically constrained.

You can also edit groups of control points by selecting them in a very convenient manner. Just hold down the left mouse button and start dragging the control surface. In response to your dragging, a box will appear showing the selection area. All control points that enter this area become selected. You can then move a group of selected points the way you would move a single point, vertically constrained. To add points to the current selection, press the SHIFT key before starting to drag the control surface. To deselect the currently selected points, simply click the control surface anywhere.

You can press the right mouse button on the control surface to select all control points.

You can zoom in the control surface by first holding the ALT key and then dragging the control surface. In response to this, you will see two vertical red dashed lines specifying the zoom in area.

To fully zoom out, hold the ALT key and double-click the left mouse button.

While the control surface is zoomed, you can scroll the visible control surface area. To scroll this area, hold the CTRL key and drag the control surface, and then move the mouse to the left or to the right.

Pressing this button will display the plug-in's info screen. This screen shows copyright and registration information, and contains the "Help" button which opens the bundled HTML help file you are reading now.

This screen also contains the following global settings. A global setting is one that affects all Pristine Space instances in all audio host applications. All settings except the "Auto Apply" take effect only after the plug-in instance is reloaded or audio host application is restarted.

NOTE: These global settings can be considered 'advanced' settings. Please make sure you fully understand their meaning before making any changes. Also, make sure your audio host supports the settings you choose.

The "Set Inputs..." and the "Set Outputs..." selectors allow you to choose the number of inputs and outputs the plug-in supports, respectively. These numbers are reported to the audio host when the plug-in is being initialized.

The "Set Latency..." selector shows you the list of the possible processing delays (in samples). Bear in mind that the lower the processing delay you select the more CPU resources the plug-in consumes. If you do not plan to use Pristine Space for tracking it is suggested to choose latency values of 8192 or 16384. For 96k projects you may even choose the value of 32768. NOTE: It is highly suggested to set your audiocard block size (latency) in accordance with the latency of the plug-in. The most suggested audiocard block size value is four times larger than the value you choose with the "Set Latency..." selector. For example, if you choose "64" then it is suggested to set your audiocard block size to 256 samples. For plug-in latencies above 1024 you may choose the audiocard block size of 4096 samples.

The "Calc" selector allows you to force a specific calculation (optimization) mode. For example, on the latest 64-bit AMD processors it may be useful to enable SSE operation mode because by default Pristine Space uses 3DNow! optimization on AMD processors. FPU mode is the least preferred mode for use with the latest processors, but enabling it without any efficiency loss may tell you that your system's memory bandwidth is limited for convolution tasks. Also note that the "Calc" button shows the mode currently being used (e.g. "Calc: SSE"). Also note that the implemented SSE support is compatible with SSE2 (SSE2 by itself does not add anything specific which can be utilized by Pristine Space to bring a speed boost).

The "Auto Apply" switch is enabled by default, forcing Pristine Space to recalculate the loaded impulse after each envelope change. You can disable the "Auto Apply" mode to make the overall workflow go smoother, but then you will have to press the "Apply" button manually in order to apply any changes made to the envelope.

The "PDC Disable" (PDC means `plug-in delay compensation') option can be used to force the plug-in to report zero latency to the host. In some cases, on dual processor systems, this allows you to run two instances of Pristine Space for the price of one. Some hosts (e.g. Cubase SX) do not run plug-ins with non-zero latency on two processors in parallel. Please note that with this setting enabled, the host will not be able to compensate for plug-in's latency. This setting can be especially useful during tracking, on dual processor systems and multi-processor-enabled audio hosts, with a low latency settings (64 to 256).

The "No Lo Quality" global setting disallows the use of the Low quality convolution mode. A convolution channel's quality setting will be ignored and the Max quality setting used instead. Disabling the Low quality mode this way frees up considerable amounts of system memory (about 30%, e.g. plug-in will use 2 megabytes instead of 3 megabytes, of memory). It is highly suggested to enable this setting if you do not plan to use the Low quality mode at all.

The "Zero Latency" setting enables a true zero-latency processing mode. Please note that this mode has its own limitations. It will work only with audiocard block sizes (latencies) which are a power of 2, in between 32 and 16384 samples. For example, if the current audiocard block size is 5512 samples, Pristine Space will be silent given that the "Zero Latency" mode is enabled. Another limitation this mode imposes is the stability of the CPU load: you may experience CPU spikes and overloads, especially if you are using more than two instances of Pristine Space. This mode can be useful for tracking sessions, when you don't need many plug-in instances, but where zero latency operation is useful.

Some impulse responses (e.g. linear phase filters) have pre-ringing before their initial spike. For the tonal balance of these impulse responses to be preserved, the pre-ringing must be included; the drawback is that the processed wet signal will play later than the unprocessed dry signal.

Pristine Space's "Latency +512" mode solves this problem. When this mode is enabled a red line in the wave display indicates the time when the dry signal plays; the impulse response can then be positioned, using the offset control, so that the initial spike coincides with the red line. When the offset control is set to a negative value the impulse response will shift to the right, when it is set to a positive value it will shift to the left.

When using an impulse response which starts with an initial spike and has no leading samples, the spike can be quickly aligned to the dry signal by moving the offset control fully anticlockwise so that the response is shifted by exactly 512 samples to the right. When using an impulse response generated by Impulse Modeler with the "Add Pre silence" option enabled, there is no need to alter the offset control from zero, because Impulse Modeler adds 512 leading samples prior to the initial spike.

Defining search paths can be useful when you have a situation where you load some old project which uses impulse response file which is not available in the original folder anymore. To resolve this situation simply assign the path where this impulse resides now to one of the search paths and Pristine Space will automatically locate this impulse file for you.

Search path list is available when you press the '?' button. You can define up to three search paths. Impulse file will be also searched in subfolders of the selected folder.

The "Browse" button allows you to select a search path.

The "X" button removes a search path.

Pristine Space is bundled with seven basic template presets. These presets should be used mainly as a starting point for your work, since they are not linked to any particular impulse responses. These presets are:

2ch reverb insert: can be used as a general setting when Pristine Space is used as a audio channel insert processor. You should load the impulse response in the Slot 1.

2ch reverb send: can be used as a general setting when Pristine Space is used as a send effect. You should load the impulse response in the Slot 1.

Drum ambnc and ovrhds: (drum ambience and overheads) can be used as a send effect setting for applying `advanced' drum reverb consisting of separate ambience- and overhead-mic-captured reverb impulses. You should load the impulse response for ambience in the Slot 1; the overhead mic impulse should be loaded in the Slot 2.

2-step 2ch serial insert: can be used as a general setting for serial processing, when Pristine Space is used as an insert effect, without dry signal mix. Impulse responses should be loaded in Slots 1 and 2.

3-step 2ch serial insert: this preset is generally equal to the previous preset setting. The only difference is that you should additionally load the impulse response into the Slot 3.

True stereo reverb insrt: this is a general setting for processing stereo signal with two stereo impulse responses, when Pristine Space is used as an insert effect. Impulse responses should be loaded in Slots 1 and 2.

True stereo reverb send: same as above, but for send effect.