SPROOM DSP DIY for Eurorack Synthesizer

Panel & PCB only!

Sproom, half space half room.

It´s based on the FV-1 DSP IC by Spin Semiconductor which got popular with some famous guitar pedal effects and is covering all types of quality reverbs, delays, chorus, flangers, tremolos, or combinations of them.

It´s stereo and operates with 6 MIPS at Fs=48KHz, or in other words excellent audio quality with a clean dry / wet path to adjust the amount of effecting.

It offers 3 banks with each having 8 different algorithms. In total 24 effects.The input is normalized to R. Means with just plugging a mono source into the left input, the output becomes stereo.

Each algorithm can be controlled with one of the 3 potentiometers, or by control voltage.Capable of -5 / +5V with the dedicated pot at around center position, or 0-10V with the pot fully closed. In other words, the pot acts as offset.

Fancy LED indication for clipping and CV ins.

The internal effects are tied to the IC and fixed. Bank 2 & 3 or EX1 & EX2 can be exchanged with EEPROMS on the backside.8HPDepth: 42mm+12V 92mA-12V 23mA

Find the DIY guide here

BankEffect TypePot1Pot2Pot3
INT1Chorus – ReverbVerb MixChorus RateChorus Mix
INT2Flange – ReverbVerb MixFlange RateFlange Mix
INT3Tremolo – ReverbVerb MixTremolo RateTremolo Mix
INT4Pitch Shift+/-4 semitones
INT5Pitch – Echo+/-4 semitonesEcho DelayEco Mix
INT7ReverbSizeHP FilterLP Filter
INT8ReverbSizeHP FilterLP Filter
EXT 1.1Stereo Ring ModulatorBlendCarrier OffsetChorus
EXT 1.2Reverb ReversePre-DelayDecayDamping
EXT 1.3Tape Delay 1 Head Ping PongRateFeedbackDamping
EXT 1.4Tape Delay 2 Head Ping PongRateFeedbackDamping
EXT 1.5Tape Delay 2 Head Ping Pong + ReverbRateFeedbackDamping
EXT 1.6Digifuzzer / BitcrusherSample RateBit RateLevel
EXT 1.7Shimmer ReverbDampingShimmer LevelDecay
EXt 1.8Triple Cascaded DelayRateRateRate
EXT 2.1Reverb HallSizeDelayDamping
EXT 2.2Reverb LargeSizeDelayDamping
EXT 2.3Reverb SmallSizeDelayDamping
EXT 2.4Reverb PlateSizeDelayDamping
EXT 2.5Reverb GatedSizeDelayDamping
EXT 2.6DelayFeedbackTempoDamping
EXT 2.7FlangerDelayWidthRate
EXT 2.8ChorusAmountWidthRate


The process of flashing EEPROMs can be discovered here or on GitHub

A list of available algorithms can be found here at Spin or here.

Spin provided a software to create own algorithms (If you´re a nerd :p).

Feel welcome to share your algos or experience here in the forum.Me personally would be very happy if 🙂

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