ValhallaRoom V1.0.6: Introducing Dark Room

I have just released version 1.0.6 of ValhallaRoom. You can download the demos from the usual place, and all current ValhallaRoom customers should have received a link to the updates (send me an email if you haven’t received your links yet).

In addition to a few bug fixes, version 1.0.6 introduces a new reverb mode to ValhallaRoom: Dark Room. This new reverb departs from the high fidelity path taken by the other 4 reverb modes in ValhallaRoom. It is deliberately low-fi, with noisy interpolation, no high frequencies above 11 kHz, and a late reverb that can have a low initial echo density. It also has a wide stereo image, a clear decay with lush randomized chorusing, and sits in a mix quite nicely. An added bonus is that the CPU is significantly lower than the other ValhallaRoom reverb modes.

Why add a lo-fi reverb mode to ValhallaRoom? I’m not really sure. After doing this for about 12 years, I’ve learned to follow my instincts on this stuff, even if it takes me in strange directions. Plus, I wanted to add something new to ValhallaRoom, as a way of saying thanks to all of the customers who have supported my work.

I was also inspired by some recent studies of the Lexicon 224, the EMT250, and other vintage reverbs. These early digital machines often had very noisy interpolation, sparse initial echo density (at least by modern standards), and sampling rates that seem primitive today. They also were useful for creating a “larger-than-life” sound, that is described to this day as warm and spacious. I noticed that a lot of these classic reverbs had a very limited frequency response, so I figured it would be worth adapting some of these old-school limitations to the more modern algorithm architectures found in ValhallaRoom.

Dark Room has identical controls to the other reverb modes, but produces a noticeably different initial sound. With Early Send set to 0, the Late Decay can have a marked amount of initial “flutter” or “grain,” similar to the 224 Concert Hall with the Diffusion control set low. A few usage tips:

  • The Late Size control can be used to adjust the speed of the “flutter,” with larger sizes corresponding to more obvious and slower echos.
  • By setting Early Send to 1.0, and adjusting the Early Size to 40 msec or later (depending on the Late Size), the flutter in the Late reverb can be totally eliminated. This is similar to how the Diffusion control works in older Lexicons, but with the advantage that the Early reverb has far less coloration than the series allpasses used for the diffusors in many “classic” reverbs. The Late Size can then be adjusted to get the desired stereo width – this can get really big.
  • Setting DEPTH to 1.0 results in the most “vintage” sound, while values less than 1.0 allow the user to dial in some early reflections.
  • With Early Send set to 1.0, and using larger Early Size values (>100 msec), the Late Reverb will have a slower initial attack. This is similar to how the Depth control worked on the 224 and 224X/L, as well as the Shape and Spread controls on the 480L and later reverbs.
  • The Late High Mult and Late High Xover have an effect on the initial tone of the late decay, similar to the Concert Hall algorithm on the 224XL and the Small/Large Concert Hall B on the 224. By setting High Mult to 0.1X, the user can simulate the -6dB/octave filters used on these older boxes.
  • Turn up the Early and Late Mod Depth when using Dark Room. The older algorithms used a LOT of pitch modulation to avoid metallic decays. The Dark Room algorithm uses a different architecture that is less prone to sounding metallic, but if you want that big, lush, spacey decay, modulation is a must.

Here’s a preset that can be used as a good starting point for the Dark Room reverb mode:

<ValhallaRoom pluginVersion="1.0.6" presetName="DarkStartingPoint" mix="0.289999992" predelay="0" decay="0.0265265256" HighCut="0.58523488" earlyLateMix="1" lateSize="0.720000029" lateCross="0.25999999" lateModRate="0.202020198" lateModDepth="0.430000007" RTBassMultiply="0.413333327" RTXover="0.0666666701" RTHighMultiply="0" RTHighXover="0.410067111" earlySize="0.0581581593" earlyCross="0" earlyModRate="0.0909090936" earlyModDepth="0.800000012" earlySend="1" diffusion="1" type="0.416666657"/>

ValhallaRoom Tips and Tricks: Unnatural Hall Reverbs

In one of my previous posts, I described the characteristics of “real-world” concert halls, and how to emulate them with ValhallaRoom. In general, real concert halls have a fairly fast onset of reverberation, a decay time between 1.6 and 2.1 seconds, and a somewhat longer decay time at low frequencies than at mid-frequencies. A realistic emulation would use subtle amounts of modulation, in order to create the perception of a high modal density without pitch change.

This is all fine and dandy for real concert halls, but what about unrealistic concert halls? The earliest commercial reverbs, the EMT250 and the Lexicon 224, were both created in order to emulate concert halls. With the limited amount of memory available for delay lines, both of these reverbs turned to large amounts of time variation in order to avoid metallic decays. The sonic results were big, washy, chorused decays that could stretch to 70 seconds and beyond. No “real” concert hall sounds like this – but it is a great sound. In addition, hardware units like the 224, 224XL and 480L had the ability to artificially elongate the attack portion of the reverb, such that the reverb sound would “fade in” to a much greater degree than a real hall. Not realistic, but useful for creating a bit of separation between an input signal and the reverb.

Fortunately, ValhallaRoom excels at unnatural halls, in addition to emulating the “real thing.” A few tips for dialing in an unnatural, vintage digital hall sound:

  • Set DECAY to whatever feels right. Many of the “Concert Hall” presets of classic digital reverbs have decay times of 6 seconds and up.
  • Use the LATE Bass Mult to dial in the required clarity of the decay. Setting this <1.0X will result in a reverb that gets more trebly as it decays, which can be a nice sound.
  • Turn up the modulation depth! Both Early Mod Depth and Late Mod Depth can be cranked up for that seasick decay. For less obvious detunings, use lower Mod Depth settings, but higher Mod Rates.
  • The Bright Hall reverb mode can get much deeper and random modulations than the other modes.
  • Set Early Send to 100%, Early Size to >100 msec, and DEPTH to 100%. The Depth control in early Lexicon reverbs, and the Shape/Spread controls in later Lexicons, allowed the user to dial in a slow attack on the reverb. By running the Early reverb into the Late reverb and using a large Early Size setting, you can create a reverb that fades in at the rate determined by the Early Size.
  • The Early Diffusion control can be set to lower values, to emulate the grainy sound that many of the early reverbs had during the initial attack phase.
  • Set HIGH CUT to somewhere between 5000 and 8000 Hz to simulate the dark sound of early, low-sampling rate reverbs.

The following preset implements a big digital hall sound:

<ValhallaRoom pluginVersion="1.0.5" presetName="BigDigitalHall" mix="0.425000012" predelay="0.0240000002" decay="0.0730730742" HighCut="0.44697988" earlyLateMix="1" lateSize="0.730000019" lateCross="0.709999979" lateModRate="0.155555561" lateModDepth="0.460000008" RTBassMultiply="0.166666672" RTXover="0.0787878782" RTHighMultiply="0.377777785" RTHighXover="0.474496633" earlySize="0.255655646" earlyCross="0.0299999993" earlyModRate="0.143434346" earlyModDepth="0.370000005" earlySend="1" diffusion="1" type="0.25"/>

Den (from the Gearslutz forum) posted this preset, reminiscent of the sounds of the Lexicon 224 Concert Hall algorithm:

<ValhallaRoom pluginVersion="1.0.1" presetName="BladeRunner" mix="1" predelay="0" decay="0.150750756" HighCut="0.294630885" earlyLateMix="1" lateSize="0.949999988" lateCross="0.150000006" lateModRate="0.191919193" lateModDepth="0.200000003" RTBassMultiply="0.666666687" RTXover="0.0494949482" RTHighMultiply="0.25555557" RTHighXover="0.289261758" earlySize="0.235135138" earlyCross="0.0199999996" earlyModRate="0.169696972" earlyModDepth="0.129999995" earlySend="1" diffusion="1" type="0.25"/>

A quick example of piano played through the above setting (piano played by Den):


Here’s a really big “concert hall” setting:

<ValhallaRoom pluginVersion="1.0.5" presetName="VideoIntro" mix="0.507000029" predelay="0" decay="0.300000012" HighCut="0.344966441" earlyLateMix="1" lateSize="0.579999983" lateCross="0.150000006" lateModRate="0.088888891" lateModDepth="0.280000001" RTBassMultiply="0" RTXover="0.113131315" RTHighMultiply="0" RTHighXover="0.2966443" earlySize="0.0440440439" earlyCross="0.0199999996" earlyModRate="0.169696972" earlyModDepth="0.129999995" earlySend="0" diffusion="1" type="0.25"/>

A simple electric guitar phrase (which was used on Gearslutz to test many reverb algorithms) through ValhallaRoom with the above settings:


UPDATE 1/2012: I just reread this blog post from last year (thanks to a link-back from an interesting blog post at The DIY Recordist). It is worth noting that ValhallaRoom has several new reverb modes that are well suited for emulating vintage digital halls. DarkRoom, Nostromo and Narcissus are reverb modes that are designed to have the “dark” coloration of the older reverbs, as well as a more gradual onset of echo density, noisier interpolation (to emulate the reduced bit width coefficients of the older boxes), and heavy randomized modulation.