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Other Pedals
This page is for the 'other pedals', which includes phase shifters, choruses, bass synths, tremolos, vibratos, auto wahs, delays, Leslie effects, and envelope pedals. Basically, any pedal that's not a distortion/overdrive or a compressor (since they have their own pages). I own quite a few factory produced ones and have built a few other clones and modded clones of my own. This page is a work in progress and I'll update it as often as I can. As of today, there are 70 pedals on this page.
Magnus Modulus:  With 8 knobs and four switches his one was a pretty complicated build.. It's a delay, a tremolo, and a chorus pedal all in one. To me, the echo part is it's best feature but with all of those controls you can definitely dial in some other really cool sounds with it.
Catalinbread Pareidolia Harmonic Mesmerizer:  The Blonde fender amps had an really special vibrato/tremolo circuit. 
Catalinbread describes it this way:
"Truly the “sinewave” Brownface tremolo sound, folks are looking for,  used as the starting point, but adding a lot more range of speeds and much more depth.
•Replicates early 60's fender "harmonic" vibrato.
•A unique effect mix of tremolo, vibrato, phasor, and filter.
•Extended depth and rate for more sounds and speed.
•Roll back Depth to double as a clean boost."
I really dig this one on guitar and bass, and IMO, there's no other tremolo/vibrato pedal like it. It's easy to get lost in its lush tone.

Rick Holt's Frequency Central Causality 4 MKII:  This is a really nice sounding phase shifter. It's a four stage OTA based phaser with two fixed stages and two swept stages. The Width control  defines how broad an LFO sweep the OTA's see
The Shape controls the waveform, continuously variable from upward sawtooth through triangle to downward sawtooth
The Range control defines where in the audio spectrum that the phasing happens.
Paia Gator:  A really good swell pedal that yields excellent volume swells and can also be used for a backwards sound effect. It sounds similar to a Boss Slow gear but does it a competely different way and I find it more controllable.
Boss Slow Gear SG-1:  Long since discontinued and now quite rare, sought after, and expensive, I built mine exactly to the original Boss schematic and used the exact same spec NOS components. It's an excellent sounding volume swell pedal for guitar or bass and has NO low end loss.
Soundclip coming soon
DLS Effects RotoSim:  Still my favorite Leslie emulator with controls for fast and slow speeds, with seperate levels for the woofer and tweeter, ramp up and down speed, and a slight overdrive for a 'dirty leslie" effect. Other features include a input for an expression pedal and stereo outputs.
BJFE/Mad Professor Snow White Auto Wah:  To me, this envelope pedal sounds more like a real wah-wah than  other envelope filter pedals do. The controls are sensitivity, Frequency (the range of the envelope), the Q (sharpness of the frequency) and Decay (how quickly the wah recovers. It works equally well on guitar or bass.
Echo Base: The Echo Base is a DIY handmade analogue-voiced digital delay based around the popular PT2399 delay chip. It can be easily coaxed into a very Deluxe Memory Manesque type of self oscillation, give you delays of over a second, and has a modulation section to add some subtle tape-echo style warble to your delays, or even  get Chorus and Vibrato sounds with at low delay time settings.
Boss OC-2: I call mine the OC-1 since I omitted the 2 octave down section since I play bass. An all analog, non polyphonic octaver with good tracking and a nice low octave tone. Controls are for clean and 1 octave down and can be mixed together at any amount. I built this one using the Boss schematic and used the same components as the original OC-2. Below is a quick clip that I made to give you an idea of what it sounds like.
BJFE/Mad Professor Deep Blue Delay: Although this is a digital delay, it's voiced to sound analog and it's a great one. The Deep Blue Delay is a natural sounding digital/analog delay, with analog direct signal path. It has about the same bandwidth as the classic tape echo units, and it can be used in front of an amplifier or in amplifier effects loops. It was specially designed to work well with distorted tone, as this is the most critical application, where delays often fail. You can use the pedal before or after distortion. As such, it will work exceptionally well on clean sounds where requirements are less stringent, especially in terms of echo bandwidth and repeat formation.
The delay tone was carefully tuned with lot of attention to the first critical reflection and how the repeats decay. Designed to work as an ambience delay; like that of a vintage tape echo and the repeat formation was specifically designed to allow easy setting and less critical setting of delay time. Delay times range from 25ms (fully CCW) to 450ms (fully CW)

Boss CE-2 (modded): In my opinion, this Boss Chorus is among the best sounding analog chorus pedals ever offered. I built it using the original schematic with the exact NOS components, but also added a couple of mods to make it even more versatile. An added depth switch for more depth, a chorus vibrato switch, and a bass boost for even more low end, aka the 'TonePad' mods.
John Hollis' Zombie Chorus: This is a stripped down and simpler analog chorus that was designed to emulate a Small Stone or a Boss CE-1. While it's not quite at the level of the Boss CE-2, it does have some  good sounds of its own
Earthquaker Devices Ghost Echo: The Ghost Echo is a reverb pedal using the Accutronics/Belton Brick. It also has a PT2399 delay chip in it so you can add pre-delay to the reverb ala the "attack' control. The Dwell sets the length of the reverb's decay from about 2.5 seconds to nearly infinity (almost runaway). It's actually a pretty good sounding reverb alternative to a Fender amp's spring tank.
Mini-Vibe: This one started out as a Danelectro Chicken Salad which is their Uni-vibe clone. It uses four photocells with a light bulb just like the original . I rehoused it from the stock plastic orange enclosure, using a true bypass switch (the Chicked Salad is NOT true bypass), alpha pots, a chorus/vibrato switch and added a Jfet boost at the output so i could have more control of its level. This is a great sounding  uni-vibe that sounds nearly identical to the original but at a fraction of the price.
Musitronics Phasor II: A great sounding phase shifter from the 70's using an electro-optical phase circuit. It uses same "photo-mod" circuit as their Bi-Phase, with rate depth, and feedback controls. These are AC powered devices. This particular one used to belong to Nikki Sixx from Motley Crue.
Mutron V (highly modified): I built this one verbatim to the original Mutron V which only has a 'Range' control and the 'hi/lo' switch. Then I added attack & release controls as well as an input sensitivity, a clean blend and a Jfet clean boost on the output, with an output master volume control. It's an awesome sounding envelope filter for bass now, is highly adjustable, and much more versatile than the original.
Pearl OC-7 Octaver: Still one of the most loved octaver pedals by bass players, the Pearl OC-7 has been discontinued for decades now. Along with a clean, uneffected 'normal' output, it's four-way mixer allows discrete blending of 2 octaves down, 1 octave down, and 1 octave up. I built this one form the Madbean 'Lowrider' pcb which is an exact reproduction of the original and it worked perfect the moment that I fired it up.
Lovetone Meatball: These UK made envelope pedals are no longer made and the originals go for big bucks so I just had to clone one. Many say that it's the best sounding envelope ever offered, and they are indeed a great one. With FOUR rotary switches and 6 pots, it was kind of a wiring nightmare but I did still manage to fit it into a 1590BB enclosure. I did add one mod to it which is a 'Moog' filter select switch which changes the low end sweep Q of the filter. My build's gut shot can be viewed HERE.
Mutron III: The Mike Beigel designed vintage Mutrons from Musitronics are highly sought after envelope pedals. I used to own several of them when they came out in the mid 70's so I built this clone of one and then modded for bass use. I did away with the high pass and bandpass settings (since they cut most of the low end from the pedal), made it true bypass,added a sensitivity control, and added a 'Moog' filter switch. The originals are excellent sounding 'auto-wahs' and mine is capable of sounding just like one, only with a little more adjustability.
WMD Superfatman: This envelope pedal is based on a Mutron III but with a ton of options, including a sensitivity control, depth & frequency controls, sweep up or down, a 12 way rotary for the range, HP, BP and LP filters, a clean blend, a phase switch, an LFO with variable wave shapes as well as an expression pedal input making it much more adjustable and versatile. It actually sounds similar to the Lovetone Meatball but with even more options. IMO, this is a great envelope pedal for those that want to be able to tweak one to the max.
Source Audio Orbital Modulator: Source Audio's OM has quickly become my favorite phase shifter. It's also capable of excellent flanger, chorus, & tremolo settings and can even do rotary speaker and univibe emulation. The Soundblox2 series have a pretty small enclosures but still have a TON of options/controls for dialing in exactly what you want. The controls are very user friendly making easy to operate and adjust quickly. You can store two presets accesible via the two footswitches. I really feel that Source Audio has hit it out of the park with this one. Rather than try to explain all of its features, you can view the owner's manual HERE.  You also view some of its factory recommended settings HERE.
Electro Harmonix Doctor Q: This envelope pedal has been around for a long time. The original has a mini toggle switch that switches between hi and lo modes but I found the hi mode unusable so I omitted it. I also added and attack control so it can now go from a 'quack' to a smoother 'wah' type of enevelope. It does add a bit of distortion, but that's just the 'character' of this pedal which I think is pretty darn cool.
Source Audio Manta Bass Filter: Source Audio's Manta is my now my personal favorite envelope pedal. It's also capable of being an excellent phase shifter, and I was able to adjust it to simulate a very convincing Leslie 147. I was lucky enough to get this pre-production model two weeks early (production units are available now.).  Like all Soundblox2 series, they have  a small enclosures but have a lot controls for dialing in exactly what you want. Again, the controls are very user friendly making easy to operate and adjust quickly.  I've found it to track envelope signals better than any other envelope pedal offered. If that's not enough, it also has 8 overdrive voices with adjustable gain control so you can add a little or  a lot of dirt to your tone. The Manta's owner's manual can be viewed HERE
Source Audio Programmable Eq: And yet another great pedal from Source Audio. This little graphic equalizer sounds great and is packed with features. 4 presets, + an or - 18db of boost/cut per band, extendable 8th band  (62hz) for bass, an output level for clean boosting or gain matching, auto scrolling thru the presets (for tremolo effects) and more. I find it to be extremely quiet and transparent. If you're looking for an eq in pedal form, this is the one for you. More info on the Source Audio website can be found HERE ,and it's owner's manual can be found HERE
Tech21 Bass Boost Chorus: This is an awesome chorus pedal for bass and is now my favorite bass chorus pedal. It has a lot of control of its tones and can get a heavy chorus sound without the 'sea-sick' warble that almost every other chorus pedal has. If your looking for a chorus pedal for your bass, this is the ONE to get.
Boss OC-3 Octaver: The successor to Boss's OC-2, this one is digital, but includes a poly mode as well as a drive control for adding some grit/distortion. I think that I slightly prefer the OC-2 but this one is nearly as good and is a nice alternative.
Boss SYB-5 Bass Synthesizer: For the money, I think that is is a very nice bass synthesizer. It's very adjustable from subtle to crazy synth sounds and defitely woth checking one out.
Digitech Bass/Synth/Wah: This is one of the first bass synth pedals that I purchased and I still have it. You can get these really cheap used, but they are even inexpensive brand new. It has a nice envelope/ wah filter in it as well as quite a few synthesizer modes that sound very nice. For the money, you really can't beat it.
Modulation, Echo, Reverb, Chorus, Rotary, Phasers, & Tremolo
Earthquaker Devices Hummingbird: A very unique tremolo based on the Vox repeater.. Rather than a smooth sine wave trem, this one creates choppy/stuttery volume tremolo. This 100% analog pedal does slow pulses, ping pong delay-like stutters, light blipping, through machine gun stutter tremolo.
Controls:
Depth: Controls amount of modulation from barely there to full signal chop at full bore.
Rate: Controls the speed of the LFO. Clockwise for faster, counterclockwise for slower.
Level: Controls the signal input level which ultimately controls the output level. Clockwise for more, counterclockwise for less.
Mode: Fast/slow switch for LFO rate. Mode 1 is slow, Mode 2 is fast. I made mine so the speed modes overlap.

Boss CEB-3 Bass Chorus: I bought this one quite a while ago after searching for a nice sounding bass chorus. At that time I thought it was one of the best bass choruses after buying alot of them and I do still like it alot. It's great if you don't want to spend the bigger bucks for the Tech21 Bass Boost Chorus above, but IMO, the Tech21 Bass Boost Chorus is a much better sounding unit..
Octavers
Volume Swell Pedals
Envelopes, Auto Wahs and Filters
Bass Synthesizers
Equalizers & Tone Enhancers
MXR Bass Envelope FIlter: The MXR is a very nice sounding bass envelope filter. Its' no longer my favorite ever since the Source Audio envelope pedals took that spot, but it is still an excellent bass envelope filter and is extremely easy to operate.
Source Audio Bass Envelope Filter Pro: Source Audio's BEF Pro and Manta are my now my two personal favorite envelope pedals. The Pro is the predecessor to the Manta, and like the Manta, is also capable of being an excellent phase shifter. Like all SA products they have a lot controls for dialing in exactly what you want.The controls are very user friendly making easy to operate and adjust quickly.  I've found that both of them track bass envelope signals better than any other envelope pedal ever offered. The Pro doesn't have the included distortion like the Manta, but does have a 7 band graphic equalzer and the capability of saving 6 presets. If you don't require the distortion, want more presets, a full graphic EQ and a bit more control this is my  recommendation as an alternative to the Manta.
Seamoon Funk Machine: The Seamoon Funk Machine was one of the very first envelope pedals ever produced. I bought my first one back in 1973 and I always loved it. I still have it somewhere but can't seem to find it, so I made an exact clone of the circuit and then added a clean blend to it to make it a bit more versatile. It adds a little dirt and coloration of its own but it still does sound really good.
Electro Harmonix Enigma QBalls: This one was another one of my favorites before the Source Audio.envelopes came along. I still dig it and it's more like the Mutron/Qtron circuit but with more controls. It can get very 'peaky' level-wise if you're not careful, but it does sound very good.
Musitronics Phasor II clone: I dig my original Phasor II so much that I wanted to make an exact clone of it only in a smaller enclosure and able to run on a 9 volt standard center negative power supply. I 'm pleased to say that it came out awesome and it sounds identical. IMO, these are awesome phase shifters using 6 opto-devices for their colorful lush tone. The internal pic is HERE
Mutron III (clone #2): For my second clone of the infamous Mutron III, I used madbean's 'Naughty Fish" pcb, but then added a sensitivity control, an output level control, as well as a switch to go between the stock sweep filter and a 'Moog' type of sweep filter. This one sounds and does everything that the vintage original one can, and way more.
DOD 440 Envelope Filter: With the vintage ones getting to be pretty rare and expensive these days, I built an exact clone of the original circuit. It uses a dual Vactrol opto device (VTL5C4/2) for the envelope, sounds great and is extremely easy to dial in. They also made an FX25 envelope (which I've also built), but I prefer the 440 by a quite a bit. It's no wonder that DOD has just released a re-issue of this great envelope pedal. The gut shot of this build is HERE.
DOD FX25 Envelope Filter: The FX25 was introduced in 1982 and this clone is the earliest version of it. It  uses an OTA (LM13600) for the envelope. The stock unit uses a twin filter which makes it a bandpass filter, but I added a switch  to select between the stock bandpass and a low pass filter which I find makes it much more useful. I also added a clean blend which I find makes it way better. The pic of the internal circuit can be viewed HERE.
Maestro Stage Phaser: When Maestro introduced their first phase shifter, the PS-1, I immediately loved it. It came in a large steel enclosure with three large colored rocker switches to choose between its 3 speeds with NO footswitch and was designed to be mounted on a mic stand. It went thru 3 incarnations (the PS-1, the PS1-A and the PS1-B with variable speed pot) before being discontinued. The next generation of Maestro phase shifters were designed and built by Moog, and the first one was the Stage Phaser. It came in a huge aluminum enclosure and you'd step on the entire pedal to turn it on and off. This is a great sounding phaser using three LM13700 chips to acheive its 6 stages of highly colored phasing which its depth can be adjusted with the balls control. The small toggle at the top switches between 5 and 6 stages of phasing.
Maestro PS1-A Phase Shifter: Maestro's first phase shifter that was actually not in pedal form, but was powered on AC and actually made to be mounted on a mic stand. It did have an optional foot switch that plugged into it ( I used to have a couple of them) and I thought that they always sounded great. This one uses six stages of JFets and dual opamps to produce it's lush phasing. NO knobs, with three switches to control the 3 speeds, and it ramps in speed between them. Most notably used by John Paul Jones on his fender Rhodes on 'No Quarter'. The original's input impedance is quite low, and it did lose some top end with a passive instrument, so I added a Jfet buffer on the input. It was also not true bypass, but I made mine true bypass and added a trimmable Jfet booster on the output to match the circuit's slight loss of volume. I also made mine run on a standard 9 volt power supply, and it's still one of my favorites. It's internal pic can be viewed HERE.
Electro Harmonix Small Clone chorus: IMO, the Small Clone was always a very nice sounding chorus pedal and no chorus collection should be without one. It and the Polycfhorus were Kurt Cobain's chorus pedals of choice and they are still very popular today.
Electro Harmonix Octave Multiplexer: I built this one by etching my own PCB for it. Even the layout of the board matches the original 1975 version, While testing it, I wasn't all that thrilled with its tracking and slight volume loss so after modding it for better tracking and installing a Jfet booster with a master volume control I really dig this octaver now. The gut shot can be viewed HERE.
Valve Wizard U-Boat: From the designer of the Engineer's Thumb compressor comes the U-Boat, a one octave down Sub Octave/Synth effect. You can view the plans to build it and get a lot more info HERE.  The original uses a buffered bypass but I made mine true bypass. The original circuit only has one knob (a blend) plus an internal trimpot to adjust the level of the sub octave level. It also has a toggle that switches from bright to mellow (on the sub octave only). I found the adding a Jfet booster to the output allowed me to have even more control of it's overall level and mix so my version has an additional level control (the gray knob). it's definitely a unique and original effect pedal. The gut shot can be viewed HERE.
MXR Envelope Filter: MXR's first envelope filter, and IMO, they still sound very good. I etched a pcb for this one that is an exact clone of the original. I did do one mod that was to add a depth control, but otherwise, it's completely stock. The internal pic can be viewed HERE.
Electro Harmonix Small Stone phase shifter: I really dig the old vintage Small Stones. I built this one for the Tonepad circuit which uses 13 transistors and 5 OTA opamps. It sounds absolutely great. The only issue with the vintage ones is that there is some volume loss, but I corrected that in my build. I was amazed to get such a large and complicated circuit in a 1590B but it fit in there easily. (the gut shot can be seen HERE). It's very simple to operate with only a Rate control (speed)  and a 'Color' switch which changes the depth of the phasing.
Chunk Systems Agent00Funk envelope filter: To me, this is an often overlooked envelope filter that sounds awesome. The controls consist of 'Pitch' (which is a  frequency range control), 'Smoothness' (the attack and release speed), 'Sweep' (the width of the frequency sweep), a 'Squelch' (the resonance/depth of the filter) and an up/down switch which determines which direction the filter sweeps. It also has an extra  envelope in jack which mates with their Brown Dog gated fuzz for an even more 'synthesized' effect. Due to the complexity of the circuit I made a pcb from the factory schematic for this one and I couln't be happier with the result. The gut shot pic can be viewed HERE.
Electro Harmonix Electric Mistress: The 100% analog EHX Electric Mistress has been around for ages now and are still one of my favorite flangers, but also can be a nice chorus, or both a flanger and chorus used simultaneously,  I built this one from Madbean's "Current Lover" PCB and it sounds just like the vintage original. This one is a fairly extensive build with a large PCB loaded with a lot of chips, caps and resistors. It took me a little while to dial in the internal trimmers to get it to sound the way that I wanted it, but once I did, I love it This one is housed in a much smaller enclosure (a 125B) than the large vintage ones and runs on a standard 9V adapter. The gut shot can be viewed HERE.
Ibanez/Maxon F-301 Flanger:  I built this one from the Tonepad layout. I prefer the Electric Mistress over it but this one is pretty nice flanger too. All analog and a large PCB with alot of components so it just barely fits in a 1590B. The gut shot can be seen HERE.
BYOC Divided Octave: This one was built from a kit made by Build Your Own Clone (BYOC). It's a clone of a vintage Mutron Octave Divider that are commanding very high prices these days. It's a pretty complicated build  (see the gut shot  HERE). It's a really cool analog octaver featuring a Mix (clean blend) control and a tone control for the sub octave. It also has a green ringer that you can switch in or out that works on both the clean and octave signals.
Boss Slow Gear SG-1 #2:  For my second slow gear clone, I etched a PCB for it in order to fit it in a smaller enclosure (a 1590B). To make it even more versatile, I added a clean Jfet booster to the output with an output level control. The gut shot can be viewed HERE.
MXR Phase 90 Script logo:  One of the earliest phasers available, the Phase 90 is still a lot of people's favorite phase shifter. It's a 6 stage phaser and sounds great with guitar or bass, so I think that eveyone should own one of these.
DOD FX22 Vibro Thang:  This was made back when DOD gave their pedals some crazy names. It's a very nice vibrato pedal but the phaser is just decent an definitely  isn't one of the best phase shifters out there
TC Electronics Hall of Fame Reverb:  This is a VERY nice reverb pedal and sounds great on all of its selectable algorhythmns (i.e. hall, plate, church, spring, mod, ambience, gate & room), plus it has an additional 'Tone Print" mode where you can download other people's favorite settings, or use the software to create you own. It's quite an achievement for a reverb unit in pedal form and it doesn't take up much space to boot.
Source Audio Dimension R:  My favorite reverb pedal of all time. Even though is has a bunch of controls and it extremely flexible, it's still super easy to operate and dial in its great reverb tones. Once again, Source Audio has created another winner!
Electro Harmonix Pitch Fork: New from EHX comes the Pitch Fork Octaver. It is not a true bypass pedal but the buffered bypass is excellent. It does both polyphonic octave up and down or both simultaneously, as well as multiple harmony intervals. If you connect an expression pedal to it, it'll also do whammy effects, all in a small 1590B enclosure. This is an awesome pedal at any price, but the street price is only $131!!!! 
Digitech Drop: Digitech's new 'Dropdoes just that. The rotary knob selects the drop in ptich in 1/2 step intervals all the way down to a full octave polyphonically and it sounds great. It's slightly larger than a 1590B but it's also thinner. Another highly recommended octaver for bass.
Digitech Bass Whammy: Digitech's original discontinued Bass Whammys were going for very high prices but, in my opinion, that'll soon change since their new Bass Whammy came out. I think that it does everything that the original did but better and I paid only $169.99 shipped from Prymaxe with an online coupon. IMO< that's super cheap for a pedal that sounds as great as this one does.
Behringer US600 Ultrashifter/Harmoinst:  This is basically Behringer's version of an EHX pog or Pitch Fork. I think that it's a very nice sounding polyphonic octaver and is great if you don't mind the Behringer branding, plastic enclosure and general light duty construction. That said, I haven't had a behring pedal fail on me yet.
Joyo JF07 Classic Flanger:  For about $36 shipped, there's NO WAY to beat the value of this flanger. It's  basically a clone of the vintage dark gray box AC powered MXR 117 flanger (which were great flangers!), this true bypass analog flanger sounds great with a guitar or bass and I highly recommend it if you're looking for an inexpensive flanger that rivals many boutique ones.
Behringer SM200 Slow Motion:  A great sounding clone of the Boss Slow Gear that can be purchased for peanuts. Yes, it's not of the highest quality build construction but it is pretty durable and sounds just as good as the original for only $25!!!!
Multi-Effects
Zoom MS-60B Bass Multistomp: This is a very nice sounding multieffects pedal for bass. It may not always be as good as the seperate pedals that it emulates, but it's very close and sometimes dead on at replicating them. Plus it has a TON of other effects like envelopes, octavers, reverb, chorus and compressors that sound great and some of them are exceptionally good. It's a little complex to quickly adjust/dial in the pararameters and to set up the patchs (effects order) but once you learn how to it's great.
Zoom MS-70CDR Bass Multistomp: Another great sounding multieffects pedal from Zoom. This one is dedicated to chorus, delay and reverb units and 90% of them sound excellent.
Zoom B2.1U Multieffects pedal: I bought this one when it first came out, and while the newer multi's are better, it still has some really good sounds in it, plus it's a lot easier to operate than their two multistomp pedals above
Preamps and Enhancers and Emulators
Digitech Jimi Hendrix Emulation Pedal: This one is actually designed for guitar but it also works well on bass. The modeling presets have a fuzz face and a univibe as well as treble and bass controls and their prameters can be adjusted. IMO, it's awesome on guitar and can be adjusted to sound very good on bass
BBE Sonic Stomp: More than just a treble and bass equalizer, the Sonic Stomp is designed to correct phase discrepancies to yield more punch and clarity to you instrument. I first built it stock, but then  added a midrange control since I found it to be a bit too scooped sounding for my taste. It sounds really good now. The gut shot can be viewed HERE.
Aphex 'Big Bottom' Bass Exciter: Aphex's Bass Exciter uses their Aural Exciter citcuitry to add puch to your tone without stressing your speakers. With adjustable frequency controls for the highs and lows and a blend control for each you can reshape and taylor you bass tone with subtlety or drastically. It also has an XLR direct output with a ground lift switch plus the ability to be powered by 48 volt phatom power
DOD FX10 Bi-Fet Preamp: DOD's Bi-Fet preamp is often used to make acoutic guitars sound fuller and punchier but they also are great on bass. It can boost your clean signal as well as reshape your tone with its 'Tilt' tone control which cuts highs and adds bass counterclockwise and boost the highs a cut a little low end clockwise, but even with the treble fiully boosted it still retains a lot of low end. I dig this little pedal more than most boosters. The gut shot can be viewed HERE.
JohnK FETF2B: This one is my own design that sounds just like the Alembic F2B tube preamp, only using Jfets, and in pedal form. It can be used as a clean boost or to add treble and/or bass for a full and punchy bass tone. Due to popular demand, I am offering a few of these for sale HERE. The gut shot can be viewed HERE.
Electro Harmonix B9 Organ Machine: I really dig this pedal. both on guitar and bass. It emulate various organs and it does it very well.
MXR Phase 45 (script logo version):  MXR's phase 45 is a two stage phaser so the phasing effect isn't as deep as their Phase 90 but it still sounds great. The gut shot of my build of the Phase 45 can be viewed HERE.
Meridian Funkulator: From Italy comes the Meridian Funkulator. Mine was laser etched by 'jwr' on talkbass. I actually like this all analog combo of an  octave up, octave down /envelope pedal. The envelope part isn't really anything to write home about, but when combined with the octaves, you can get some pretty cool sounds out of it. I found the build quality to be poor, and mine's set screw knobs came  mounted on knurled shafts and were sticking up about 3/8" above the enclosure until i shortened the sh,afts and installed new knurled knobs on it. It also made extremely loud pop/thumps through my amp and my bass's volume control would create a lot of static since there was DC on the input, but after modding it to remedy those isssues, I'm pretty pleased with it.
Behringer BUF300 Ultra Bass Flanger:  Only $25 brand new shipped gets you Behringer's clone of a BOSS BF2-B flanger. IMO, it's a decent flanger for bass and an accurate sounding clone, but it won't be replacing my Electric Mistress anytime soon.
DOD 201 Phasor:  DOD's 201 was their first phaser. Another two stage phaser, its schematic is identical to MXR's Phase 45 but with some component value changes. It sounds nearly identical but I find it to have a little more lows and a little less highs.
Barber Linden: Dave Barber's version of the eq section of an Ampeg fliptop amp. It runs on a standard 9V power supply or a single 9 volt battery, but is internally voltage multiplied running the circuit on 48 volts giving it tons of headroom and punch. The mini toggle selects between two different frequencies for the treble control, and the Bass pot is a push-pull with two different bass frequencies and curves. It can be used as a clean boost, or you can boost or cut the treble and bass to enhance your bass's tone. I love this one and use it as an 'always on'pedal. It has been discontinued for a while but they're available on the used market for about $100 and, in my opinion, are well worth twice the price.
Ampeg Sub-Blaster: The Ampeg Sub-Blaster was discontinued in 2006 and less than 1000 units were produced so they're fairly hard to come across. I found the original Ampeg schematic for it so I drew up and etched a PCB for it. IMO, this is a nice sounding analog octaver and it tracks very well but found its output to only reach unity at best, and the octave was actually below unity so I added a 10db clean boost to its output. I also added a relayed true bypass to it. The gut shot of my build can be seen HERE.
Musitronics Mutron III: Yet another Mutron III clone, but this time I managed to squeeze it into a smaller 1590B enclosure. It also has a relayed true bypass with a soft touch stomp switch. It's an awesome sounding filter
Electro-Harmonix Clone Theory:  As far as I know, there are at least 4 versions of the Clone Theory. The first one used an SAD1024 chip but suffered from lots of noise (hiss). The second one used the MN3007 chip which is nice and quiet, and retained the 'edge switch of the previous verison.. By the late 70's the MN3007 version replaced the edge switch with a "flange' mode and that's the version that I built, only in a 1590BB as opposed to the large vintage EHX enclosures. IMO, it's a really nice chorus/vibrato and is actually a nice flanger too.
 
Their most recent version is in a 1590BB and  has a rotary 'mode' switch (Chorus I, Chorus II and Vibrato). I prefer the version that I built but rather than hunt down a larger vintage one, I built this one instead.
MXR Phase 100 Script logo:  MXR's Phase 100 is a really nice phase shifter. Despite the rumors, it has absolutely nothing similar about it to their infamous Phase 90. This one uses 3 dual Vactrols for the phasing as opposed to Jfets (in the Phase 90). This one is an exact clone of the original ight down to the PCB's layout of components. I also installed a relayed true bypass and a status LED which the original didn't have. 
TC Electronic SCF:  The TCE Stereo Chorus Flanger (SCF) Has been around for a very long time and still remains the favorite of many users of it. This all analog pedal is AC powered and has the famous silky smooth chorus that it's best known for. The pitcj modulator is a bit subtle and the flanger isn'tas deep as some, but it really is an excellent sounding unit.
Fredrik Lyxzen's Arcadiator: The Arcadiator is a bit crusher, complete with octave up and down modes. IMO, it's a crazy sounding pedal. Its tracking is pretty glitchy but it is capable of a TON of cool sounds. The gut shot of my build can be seen HERE.
Musitronics Mutron III: One more Mutron III. This 125B version features all top jacks (in/out & DC). This version also has an output level control.
Roger Linn Adrenalinn III: A very extensive multieffect that even includes the infamous Linn drum drum machine. A zillion effects in this one, including the best fretless emulator that I've ever heard. There's just way too many effects to descibe, but you can read ALL about it HERE.
Electro Harmonix C9 Organ Machine: Another organ simulator with 9 more organ voices.
Electro Harmonix KEY9 Electric Piano Machine: EHX's piano emulator. Another great offering for Electro Harmonix
AMT CN-1 Cabinet simulator: A pretty nice cab sim that allows you to adjust the size of the cab, the magnet of the speakers, and the position & turning of the mic.
Electro Harmonix Bass Micro Synthesizer: My current favorite synthesizer for bass. This one is the larger previous version which many think sound better than the later/current 1590BB sized ones.
Seamoon Funk Machine #2 (1590A version): Since I always loved my original Funk Machine that I bought back in 1973, they have become an extremely rare find these days. I have seen clones of them recently, but if you've never owned and played thru an original it's difficult to tell if someone's clone sounds correct due to the now obsolete components that were used back in the day. Even most of the schematics posted online have a couple of errors, so I had to tweak mine a bit to sound like my original. I also added a clean blend so you can dial; in the clean signal with the envelope. It just barely fit in a 1590A but it was well worth it. The internals of this pedal can be viewed HERE.
Donner Effects Jet Convolution flanger:  At $28 this on is a no brainer. It's an awesome sounding flanger and it comes in a tiny (1590A enclosure). It rivals even boutque flangers at ten times the price. If you're looking for a flanger that won't break the bank, this is it.
MXR M-117 Flanger:  MXR's M-117 flanger has been around a long time now and it well lover by guitars, keyboards and bassists alike. I build this one using vintage components using madbean's colosalus PCB. I then added a relayed true bypass, with top input & output jacks including the DC jack. It's a g great sounding flanger
Fredrik Lyxzen PWM Phaser:  Instead of using matching Jfets or opto devices, Fredrik designed this phaser to use pulse-width modulation chips and it sounds very nice.

The gut shot of this build can be vied HERE.
Echoplex (Solid State) Echo:  A friend of mine wanted a pedal version of an echoplex so I built him this one. It uses a PT2399 chip for the delay but the delay tone was massaged to emulate an analog tape echo so it would work well with distortion & overdrive pedals and not sound like a typical digital-based delay. I'm very pleased with the way that it came out.

the gut shot is HERE.
Ring Modulators
Electro Harmonix Frequency Analyzer: The most useable and musical ring modulator that I've found to date. I built this one using Madbean's "Freekout" PCB which is a clone of the vintage version. The gut shot can be viewed HERE.
Electro Harmonix Attack Decay  These are very hard to find and when you do, you'll have to pay a small fortune for it. This is a great sounding envelope (volume swell pedal) with much more control than most of them. I used madbean's PCB to built this one.The gut shot can be viewed HERE.
Maestro Filter Sample & Hold: A pretty obscure and fairly rare pedal these days, the Maestro FSH-1 is an auto filter with a switchable sample & hold modulation. IMO, it's not all that great but it is certainly unique.The internals of this pedal can be viewed HERE.
PAIA Motion Envelope Follower: This one was designed in the 70's by Craig Anderton.It's not the greatest sounding filter but it IS certainly unique and cool sounding. The original has a buffered bypass but I went with a relayed true bypass. I found the output of both the effected and bypassed signals to be way below unity gain so I added a twin Jfet booster to it so I'd have control of both the clean and effected signal levels. Now it can go way past unity and be used as a clean boost, the envelope filter, or both, with blending capability. The internals of this pedal can be viewed HERE.
Malekko Sneak Attack: Sneak Attack is a digitally controlled analog VCA pedal that can also be manually triggered or used in a tremolo mode. The core of the pedal is an Attack/Decay envelope generator with separate length and curve controls for both the attack and decay segments. The envelope can be triggered or cycled in several ways using the input signal, built in footswitch, Lil’ Buddy footswitch or external clock/click track. Lil’ Buddy also expands the feature set to include tap tempo and additional, unique control over the attack and decay. IMO, it's likely is the best of its kind.
Echoplex Preamp: I built this one using the original Echoplex preamp's input circuit. It can deliver a few db of boost, but I wouldn't consider it much of a boost, unless you kick in the mini toggle which adds a TON of boost.

Words such as enhance, fatten and enrich all cover the effect that it has on your tone. Some consider it a 'tone polisher'. The circuit has a non-linear phase response which is probably  is the secret of its 'magic' tone. I personally use it as an 'always on' pedal and it seems to add more focus and punch to my bass.
Exotic EP-Booster: This one is a clone of Xotic's EP-Booster. It's not the same circuit as an actual echoplex preamp, but rather a jfet emulator of it and it does sound quite similar. The original comes in a 1590A with two internal dip switches for the fat and bright boosts, but I made mine in a 1590B and mounted them externally. That fat an bright switches are pretty subtle but are noticable, especially when you turn them off.