DIY Keeley/BOSS DS-1 Ultra - All Seeing Eye mod!!! (Disambiguation)

I am a bit fanatical about the DS-1 pedal all the sudden.  They kept sending me made in Japan and made in Taiwan models with the rare diodes and op amps, that just sound great.  But finally they sent one with the shitty Mitsubishi op amp so it's time to do the Keeley mod.

This post is a disambiguation.  There are a lot of online "tutorials" bout how to do this Keeley mod yourself, but there's a lot of vague information about the clipping modes.

After an afternoon and evening of sleuthing and experimentation let me say this.  The "SEEING EYE" mod is simply replacing one of the stock dioes with a 3mm LED which is visible on the "TONE" word on the case, you drill it out with a 1/8" bit, and glue it in, and that's the SEEING EYE mod.

The ULTRA mod is the switched part.  With the switch in the "up" position this second diode is the stock diode, a 1N4148.  The "all seeing eye" glows brightly, and the sound is very similar to the standard BOSS DS-1 tone, but with Keeley's wonderful refinements.  When the switch is down, you put a second 3mm LED in series with the stock 4148 diode, for the "ULTRA" mode.  The Ultra mode is the down switch position and there is a diode in series with an LED for the second clipping diode only.  Along with the standard Seeing Eye mod.  The Seeing Eye glows less brightly in this down switch position.  The sound is much, much louder and the clipping is reduced, along with more bass frequencies being heard.

So to wrap it up, the first diode is permanently replaced with the Seeing Eye 3mm LED in the TONE text, and the second diode is replaced with a switching array that allows to you to go between the regular stock 4148 diode.  And a second position (down) which gives the Ultra mode of a 4148 diode in series with a 3mm LED which is not visible, it exists inside the case.

This is a wonderful modification for the shitty newer $20-30 DS-1 you can find used with the annoying sound.  The older Japan and Taiwan models with the Toshiba op amps should not be modified, they sound wonderful.  But with this Keeley setup, the newer DS-1 can sound each bit as good.  I especially like the Seeing Eye mode.  The Ultra mode is a bit off-base from how a DS-1 usually sounds, so I will have to find a use for it.  I am guessing it could prove useful as a bass guitar distortion.  The Seeing Eye mode is more of a general refinement of the stock DS-1 sound.

You can see my photos below for the pedal I modified, and the full list of Keeley mod instructions on a piece of notebook paper.  I also would recommend trying an older Japanese style DS-1.  I would also recommend the Wampler mods that are available online in instructional form.  I did the "JCM" and "18 Watt Marshall" mods and they are both pretty cool.  Now I have to pick a favorite!  Or not... I have 5 orange pedals sitting here now! 

Alesis 3630 modification. Is it good? Or the worst ever?

I picked up an Alesis 3630 for $24 on eBay.  I have heard so much about them I had to get to the bottom of it myself.  Also, Billy Corgan used it in his guitar rig on the huge sounding Mellon Collie and the Infinite Sadness, and Daft Punk as a master compressor on their huge sounding albums Homework and Discovery.  So there could be something to it...

The first "mod" is to get a 2 Amp power supply (wall wart) I hear that the original ones are quite wimpy.  This part was about $18.

The second mod is to replace the caps in the power section.  This is where I ran into trouble.  I used 2,200 uF caps in all four position, but then one of them exploded.  I replaced it and it exploded a second time!  This was terrifying and disheartening.  I have heard of this phenomenon but this is my first time encountering it.  I believe that 2,200 uF was far to big a value for C2 and C3, and they were probably drawing too much power.  So I replaced them with 220 uF caps (C2, C3) and C4 and C5 I returned back to their original 1000 uF value.  I was too nervous to try 2,200 uF in there again.

So I cleaned up the mess, replaced a ceramic cap that got shattered (!!) in the first explosion, and let it run for an hour and a half.  This was nerve wracking, I kept expecting more popping caps.  After about two hours I felt OK to put it back together and start passing audio.

Let me mention the first nightmare.  When I pulled the knobs off for the initial disassembly, about 5 or 6 pot shafts got ripped out along with the knobs... nasty.  I don't know if some hapless punter glued them on or what.  So ordering replacement pots, and doing that part of the job, added a lot of extra time and work to this apparently ridiculous project.

The audio quad op amps that came stock were a respectable TL084CN (earlier revisions had much worse).  But I had to see what all the upgrade fuss was about so I installed sockets and a pair of Burr Brown OPA4227PA.  The two of them cost me about $5 on eBay.  So now my total investment in this 3630, including pots, is around $50.  Not bad.

I also replaced C16 and I think C33? (the other side of the board) with Panasonic electrolytic caps, since they are in the audio path.

Removing those caps gave me a little room for the nasty part, which was ripping apart the quad op amps with angled cutters.  Once you get one half of the op amp's legs snipped, you can just wiggle it back and forth a bit and then the other half of the legs will break eventually.  After this, pull the legs out with a soldering iron and some tweezers or grabber of some sort.  Then you can clean up the holes with desoldering braid (and a very hot soldering iron).  Once the holes are nice and open, you can put in a socket.  Then you can put in your new C16/C33.  After all this brute nastiness, now it's time to gently slide in the Burr Brown op amps... ahh....

Another word of caution.  I think the ribbon cable leading to the LED meters could be kind of delicate so be careful.  My left side gain reduction meter doesn't work any more.  I don't know why, but maybe I was rough on the ribbon.

The 1/4" jacks also needed a heavy dose of contact cleaner, and I refreshed the solder points for good measure.  I was getting some audio glitches from here but not after the cleaning.

I don't know which was more disgusting to work on, the Alesis 3630, or the Behringer MDX2100 Composer.  Both pretty revolting.  But in the end, they are both nice compressors to have working in the rack.

How does it sound?  Dirty-six-dirty is about right.  You get this kind of cassette tape, gritty, slightly dark on top, sort of big on the bottom thing.  Think Daft Punk, or Mellon Collie guitars.  Things sound a bit bulbous and sort of cartoon-like, a little low-fi or fuzz around the edges.  Which can be a useful sound, to my ears.  The Composer is a lot crisper and cleaner.  Honestly it wasn't that bad pre-mod either.  By the way--If you own an earlier '90s pre-Rev D. model, you might have to add a couple caps in the detector circuit, you can google this mod.  Mine already had them.  You can also snip some jumpers to take the gate out of the circuit and clean up the sound, but I didn't do this, I guess I wanted it 'kind of stock'.  And if you've got an early one with a comparator IC as one of the quads, that should be replaced with an op amp as well.

This sounds nothing like a DBX.  The compressor's action is not so defined or obvious, or quick I guess.  The attack and release, ratio controls are also not as responsive as I'm used to hearing in other compressors.  You can really smash the gain reduction meters, it seems a lot of people use 3630 like this.

It's too early to tell how much I'll use this, but it has a flattering sound that can work great for fattening up a thin sounding fuzz bass, for example.  I'm sure it would work great in a live-instrument rack, too.

Worst compressor of all time?  I doubt it.  Not bad.  I can't tell you how good it feels to be done with this one though.  I do plan to use it and it's been sounding cool so far!  The power supply lesson learned the hard way was probably worth the project alone.

DIY iRig Guitar to iPhone Interface

I've just finished a project I started months ago.  Here's a working layout for the IK iRig version 1 for iPhone or iPad.  I am going to use my iphone as a strobe tuner for guitar and bass setups, and for recording demo songs on trips and such.  The main advantage of me building this rather than buying it, is my construction is a lot more robust than the plastic IK unit, and I used switchcraft jacks, star quad cable, etc.  Between this, and my two Tascam iPhone interfaces (line input, and stereo XY mic) I'm covered for portable audio.  Amazing.

In use, with IK's free Fender and Marshall Amplitube apps, there is noticeable latency when playing guitar, but it's tolerable.  Also, this iRig circuit is pretty noisy, and the output is pretty low.  Thankfully IK includes a noise filter as one of the selectable effects in the Marshall app.  The sound quality of Amplitube is harsh and gritty, but, it'll do fine for jamming, writing, or demo recording.  I would not use it for critical recording.

Here is some technical information:

http://www.danacsimmons.com/content/working-iphone-audio-input

And here's the schematic, my stripboard layout, and my finished unit.

UPDATE - REBUILD ON 5-23-20

I was having some problems with my phone and my old build.  I decided rather than to troubleshoot I would rebuild in a new enclosure.  I re-used the circuit, though.  New TRRS cable, new enclosure.

It didn't work right away.  The two problems I found (d'oh!) were not sanding the paint off where the audio jacks touch the enclosure for grounding, and also had to spray some contact cleaner into the headphone/mic jack of the iPhone.  Once I did those two things it now works perfectly, very reliable, no weird cut outs, noise, etc.

Really obvious stuff.  Make sure your grounds are actually grounds.  Make sure your connections are all clean and reliable.  Had to sleep on it, but solved it quickly the next morning.

Also, some people are using the J201, or the 2N5457 in place of the BC245C.  You would have to mind your pinout (drain source and gate pins).  There are reports of different gain levels with these substitutions.  I haven't tested them.  They might be easier to find than the BC245C.

Also noticed my iphone is putting out about 0.88 V to the FET, not 2.7 V.  But it still works fine.

Here's the new re-build:

"Nigel" quad reamp and 24 channel summing mixer

This was a fun and laborious project, the offboard wiring was pretty intense, there's just a lot going on.  I still need to finish the last two DB25 snakes.  I used Edcor transformers, DB25 summing PCBs from the GroupDIY White Market, shipped from the UK, and a Par-Metal enclosure, along with Neutrik jacks.  My switches are a little cheapy but they basically work.

It's a 24 channel Folcrom-style analog summing mixer, the last 8 channels can be switched out when not in use, so down to just 16 channels, to minimize crosstalk.  Make up gain is provided by a stereo pair of mic preamps, any of your choice.

The outputs are switchable between Edcor trasformers, or 100uF Silmic II capacitors bypassed with small Wima caps for a little cleaner sound.

The unshielded transformers do not like to be close to the computer or other power supplies, but other than that they can be very quiet.  The Edcor transformers have a really nice sound, kind of "vintage."  The capacitors are quiet in any scenario.

The reamps are switchable between unbalanced 1/4" for standard re-amping, and balanced mic-level XLR for running into preamps for extra coloration of tracks, an idea I took from  Peterson Goodwyn, using H-pads.  Grounds can be lifted on the input, and there is RF filtering copied from the Jensen reamp schematic.

I used 6.8K resistors on the summing mixer inputs and other values for the 4 mono channels, see DIY Recording Equipment article for the math.  I went for about a 150 ohm output impedance when calculating the shunt resistor values.  The output Z climbs slightly to 160something when switched down to 16 channels.  I thought 4 mono channels was right for kick, snare, bass, and lead vocal, the rest of the inputs are L and R pairs for panned tracks or stereo busses.

My short review is, for rock music especially, or anything with lots of tracks, the summing mixer does indeed provide extra space and depth, dimension, to the sound vs the flat clean sound of DAW summing.  I'm all about it.  The analog summing section itself does something too that does not happen with just running a pair of preamps on a DAW summed mix, you can hear it.  The slight complication of setting up the mixdown is absolutely worth it for the sound.  The transformer vs capacitor output was a good design choice, as I prefer either one based on the program material.  I like the transformer for a little midrangier sound, with slightly rolled off high and low exteremes, and a little color.  I like the capacitor output for a very clean sound with deep sub bass.

When I plugged it in and listened to it on a rock band mix I had done, I knew that analog mixing was something of a missing link for me.  Just a little extra spice that helps things "fit together" in a pleasant way, sort of a picture frame around your careful mixing work.  It won't make or break a mix but I like the subtle detail it adds.  I cannot wait to add hardware EQ and compression to the stereo bus.  In the mean time Waves NLS and software comp/EQ are good stand-ins.  I really am curious to see what a real full-on mixing board will do now.  I've got my eyes on the Allen and Heath ZED series by the end of the year.

ADDITIONAL INFO AND DETAIL

Preliminary diagrams/not used.  The one on top is the idea to use a 10K:10K line input transformer on every channel of the summing mixer.  I decided not to do this, the wiring, and cost, would have been outrageous.  I decided to get my mojo on the outputs using only a pair, which is what the second two diagrams are attempting to do.

Also if you look at the small handwriting you will see a list of more expensive and fancier transformers you could use instead of the cheap but decent Edcor.  These would be low impedance output mic matching transformers I think anywhere from 200:200 to 600:600 would probably work.  Not all manufacturers use the same impedance for this type of transformer.  I end up using the capacitor output most of the time anyway, and get my transformer sound from the make up gain preamps.  The 600:600 Edcor just offers "more color" if needed.  Kind of sounds "Vintage."  NOTE: I did not use any of these diagrams it was just brainstorming.  See below for what I think I did.

Here is the output section.  I'm super paranoid about phantom power so I used capacitors when bypassing the transformers.  Use two 4PDT switches, one to route the inputs of the transformers/caps from the summing mixer, and the other switch to rout the outputs of the transformers/caps to the XLR jacks.  Since this signal is balanced the caps are configured in +/- pairs to work in place of the transformers.  The transformers are 600:600 Edcors but there are many others that would work.  The caps are 100 uF Elna Silmic II bypassed with .01 uF Wima film caps (parallel wiring).  You can probably play with these values too, or even skip the small bypass caps altogether.  I was just sort of copying Jeff Steiger's VP312DI coupling cap arrangement.  The necessity of the small cap is debatable.  I find that these values and brands sound very good in real world use.

Here is the basic reamp idea of the Nigel.  Basically the ground lift scheme is from the Jensen reamp schematic which is much easier to read than this scribbling.  I also added an XLR output on a switch that uses an H-Pad to drop about 36 decibels, you can find calculators for the resistor values on Google search.

Edcor 600:600 transformer.

Elna Silmic II 100 uF capacitors bypassed with .01 uF Wima capacitors in parallel.  I think 100 uF is flat enough with the low impedance output to extend very low in frequency before any roll off.  I have not run it through a scope, but it certainly sounds plenty deep and low, much more so than the transformers.

This is the reamp section, I did 2 channels on each perfboard.  2 boards for a total of 4 channels.  The toggle switches between Hi-Z instrument level output (TS jack) and mic level output (XLR).  You can see the shapes of  the L-pad (TS jack) copied from DIY Recording's reamp unit, and the shape in sort of an H or a spider/crab shape of the H-Pad for the XLR output that I calculated.  The transformer is in the signal path on both jacks, the switch just changes the resistor pad networks along with balancing/unbalancing for the appropriate jacks.  Be sure to take into account the signal drop across the transformer when calculating pad values.

Reamp inputs with ground lift.  A plastic TRS jack is required to be able to lift the ground.  A metal jack will automatically be physically coupled to the chassis on the sleeve just by tightening it down, so plastic is needed here.

Here is a simple DC-blocking capacitor coupled Line 2 Mic Pad in a standalone box that you could use to run a stereo mix output into a pair of preamps.  It's not a summing mixer but it does give some extra color.  I used Vishay BC Blue 100uF electrolytic capacitors, and .01 uF worth of polystyrene caps in parallel/bypass.

BHL Phono Preamp / WAC -49- #2 with Pyramid capacitors

I built another one of these using basically the same design...see my older post for the layout and general plans if you want to do one.  This time I used vintage USA Pyramid paper-in-oil capacitors for the 1 uF coupling caps.  The sound is even fatter and smoother than the standard Russian caps.  Ever so slightly, of course, but I appreciate the difference.  I think cap choice makes a pretty big difference in a preamp like this, I've read other builders say the same.  One guy used cheap panasonic film caps I think and it didn't sound as good to him.  This is no place to skimp when buying parts.  After all, this is an audiophile piece of equipment.  I had to sand the leads on the big caps clean because there was wax and junk all over them.  They soldered up fine, and work perfectly, despite their old age.  The best part is how cool they look, obviously, and the nasty wax coating that's all over them.

The other difference this time around is I used 100 uF bypass caps on all four JFETs, in parallel with the 50 ohm resistors.  The output is nice and high and easily matches a CD or MP3 of the same material in volume.  I would say that this is an essential modification to the stock BHL unit, I don't know why he didn't design his kits with more volume.  The level with no bypass capacitors in place is just not adequate.  The nice part about working on stripboard like this is it's easy to fit new parts like that, although a redesigned layout with the 100 uF caps specifically placed would probably be more elegant and not so tight.

This thing truly sounds great, and is very quiet.  The next step will be to build a dedicated 20-30 volt regulated DC power supply, and to finally ditch the old Technics direct drive for a better turntable.  I've got my eye on the Audio Technica LP1240 and various Shure and AT cartridges.

I gave the old one to a friend in need.  Things are sounding good in here.

Technics SB-LX30 speaker mods, stage 1

I found this post ages ago in 2001 when I was starting college http://www.enjoythemusic.com/under200speakers.htm about the good value of the Technics SB-LX30 speakers.  I went for the big ones for the BASS, you know.  They've been in so many rooms, houses, cities, and states by now, sometimes used and not, and in 2014 I finally started the modification process.  These speakers really bring my turntable to life and make me want to buy more vinyl records..

Rather than just using Dynamat, I added three internal braces, cutting a 1 1/2" dowel from Lowes to fit the internal dimensions, and gluing in place with Titebond, and also drilling and fixing with wood screws.  This serves to stop the rather large and somewhat thin particle board cabinet from resonating.  You can easily hear the before and after effect by thumping the cabinet with your finger.  I also used a little Dynamat where needed on the larger surfaces that weren't close to my braces.  I could use a little more on the top and bottom.  I used a 12x12" Dynamat sheet per speaker.

Then I stuffed in some Polyfil from Wal Mart, and re-connected the woofer and tweeter.  The sound is definitely tight and controlled now.  I used half a bag of "quilting" Polyfil per speaker, a single bag was enough for both cabinets for my purposes.

Stage 2, eventually, will be buying a new woofer and tweeter from parts-express.com and adding a high end crossover and thicker internal wiring, and thicker wiring from the amplifier to the speakers, which are now mounted high on a wall, on shelves I built from Lowes shelving board and shelf braces, and sitting on some foam for acousic decoupling.  But for now I'm kicking out the jams in style.  The stage 1 modified Technics are solid sounding speakers, plain yet tasty, in my medium small sized room.  Actually, I might leave them how they are since the bass is so tight and thick!  Scour ebay for a pair of these if you will and get to drilling!

Dantone/WAC "C12" clones

Here's a pair of C12 "clones" I just finished which you can read about here: http://www.gearslutz.com/board/so-much-gear-so-little-time/903043-i-just-wanna-show-off-my-c12s-i-built.html  I am not sure what to call my "company."  These mics sound fantastic.

REAMP with schematic

Here's a "reamp" I built for a friend.  I'll be doing more, including a stereo "Amp /OR/ Mic Preamp (balanced)" version for myself.  If you can follow this badly drawn schematic on note paper, that's what I used.  I took most of my tips from Peterson Goodwyn's LINE 2 AMP and LINE 2 PRE devices on diyrecordingequipment.com, he's got some great articles posted.  The balanced input jack must not be metal, grounded to the chassis, that is, because you want to be able to lift the ground with a switch if necessary for noise/ground loop isolation.  I used the Jensen reamp schematic which you can find on their website, for the RC to ground in lift position, which helps with radio frequency noise rejection.  The transformer is an unshielded 10K:600R Edcor that was an !excellent! value and really does sound fantastic.  You might need to keep it away from large guitar amp transformers, etc, in use to minimise noise.  A fancier Jensen, Cinemag etc. that has mu-metal shielding, in a can, would obviously be ideal but I wanted to save money.  I think this entire project was about $20, give or take.  You could use an XLR input, but I wanted a 1/4" since my friend will probably be using an unbalanced 1/4" line output from his mixer into this Reamp.  To save him from having to use a special cable, any 1/4" instrument cable will work with the TRS input, it will just short the "cold" signal, or that end of the transformer primary, to ground, which is fine.  Obviously you can adjust the output impedance by tweaking the 15K series output resistor, or use a pot there to get real tweaky (as in the Jensen).  You want to be in the neighborhood of a guitar or bass pickup.  You could also wire up an output attenuation pot like Jensen did but I wanted to keep it simple.  New York Dave also posted an article with a similar reamp to look at.  Another idea is to use a lower ratio transformer if you want a hotter output.  You just want to get the output impedance to simulate a typical instrument, and the input to properly load a line output, along with knocking down the level a bit.  Peterson really explains this well on his website and on Youtube.

Korg Monotribe noise mute modification

If you send this contact to a switch, and connect the other end of the switch to a ground point, you can mute the noise.  What I was not expecting is this also mutes the hi-hat, and the snare noise, so all you're left with on the drum sound is a low thud (the kick) and a slightly higher thud (what's left of the snare).

I don't know how useful this mod is, it was a bit of an experiment.  You can quickly toggle the noise on an off to musical effect, stutter.  You can also toggle away the hats, snare noise to thud-ify your drum beat, to musical effect, sort of a "drop."  Kind of cool, time will tell how much I use this switch.  I kind of like musical moments like these.  When I pull back the noise on a drum loop I am reminded of certain Radiohead moments.

DIY "Groovmaster" LP Vinyl Record Cleaning System

Inspired by this post from vinylhive.com, I followed up my earlier blog post here about a high end phono preamp, by naturally wanting to suddenly play all the beautiful records I have access to and can finally play properly.  I was getting by OK for a while, but I had a few records that were so dirty that my needle was constantly getting covered in hair and dust, and some of the records just sounded awful, so, it was time to catch up on vinyl's regular maintenance--keeping our things clean.

Here's a picture of the basic setup:

You take two 4" outdoor outlet covers, with rubber or foam gaskets attached, drill a hole in the center, then run a screw through the hole into two "wing knobs" which is a nut with a handle, one on each side, to tighten the seal around your record's label, so it won't get wet, and give you something to hold while cleaning the record.  You clean the record with a 3"-ish soft bristled brush, wet, and with a few drops of household dish soap.  After that, you gently dry the record with a lint-free towel and place it in a dish rack to dry for one hour.

Here's a picture of the gaskets glued to the outlet covers.  You should use Gorilla Glue because it is strong and waterproof.

Bill Of Materials:

Two M6 Wing Knobs (I found a sporting brand called Thule that sold these, got them on ebay). $9 for four.  1/4" in non-metric size would also be fine.

One M6 bolt 35mm long.  This worked for my metal outlet covers but was too short for the plastic ones.  For those you need a 50mm bolt or so.  I paid maybe $5 for a few of these, also on ebay.

Two SIGMA brand 4" all-weather outdoor outlet covers, purchased at Lowes for $1 and change apiece, in the Electrical section.  Which you need to attach the foam rubber gaskets with,

Gorilla Glue

Or: Two TAYMAC brand 4" plastic outdoor wet location outlet covers, with gaskets already glued.  Your covers must be 4"!!  No Gorilla Glue required.

A clean 2" or 3" brush with soft bristles.  Lowes, two or three dollars.

A plastic dish rack for dinner plates.  $4 Wal-Mart.  Mine will hold about 17 LPs.

A soft, lint free towel.  Microfiber is often recommended for minimizing lint shedding.  Might be found in auto sections of stores.  I just used some small hand towels but I'll be looking for microfiber since I did see some tiny fibers on my records after drying, looking under bright light.

Regular dish soap.

Assembly:

Drill M6 or 1/4" sized holes in the center of your round covers.  Glue on gaskets if required.  That's it.  Wing knobs will screw right onto your screws.  Most of the work is in parts-sourcing, and of course, cleaning.  These are easy to build.

Record Cleaning:

Firmly tighten "Groovmaster" label covers to your first dirty record.  Rinse record with WARM WATER.  Do not! use hot water which can possibly warp vinyl.  Brush WITH THE GROOVES of the record all the way around, never against the grooves, on both sides of the record, with a soapy wet brush (brush can be rinsed and one or two drops of dish soap applied, repeat every 2-3 records).  Thoroughly rinse both sides of record.  Gently dry the record by squeezing with palms gently between a lint-free towel and rotating, then squeezing again till fully rotated 360 degrees, and fully dried.  Remove the "Groovmaster" and spot dry any drops of water that got under on the label, or anywhere else on the record.  Place record into dish rack for drying, one hour minimum.

Result:

Records will still have collected micro dust from being exposed to air, and possibly have embedded dust from dirty playing, so, don't expect a perfectly noise-free CD audio type play, this is still vinyl being dealt with, but, expect beautiful fidelity with a minimum of noise.  If records are newer, have never been allowed to get really dirty and then played dirty, you can end up with a very quiet result.  If your towel or paper record sleeve was shedding some lint, you might want to hit each record with a Discwasher type rub down before playing for maximum clean.  If your record is excessively noisy, it is possible your water supply has mineral solids in it etc. and most would recommend to rinse the records with distilled water (can be bought in gallon jugs at grocery stores) and dry again for possibly better results.  My tap water seems to work fine.  Make sure your turntable stylus is properly cleaned, regularly.

A testimonial.  A friend gave me a funky old Steven Stills record, Manassas, for my birthday since I used to live in that awful, god-frowned town.  I thought it was as awful as the eponymous town.  Well, I ran it through the cleaning process and suddenly, I was met with Audiophile Fidelity and enjoyed the record quite a bit!  What a gorgeous tonality, and set of songs, were hidden under that thick layer of thrift-store dirt.  I'm converted to the cause of clean vinyl and clean styluses.

Stylus Cleaning:

Your stylus you can keep clean with a magic eraser, by gently pressing it into one, no rubbing at all, just press it in gently and remove.  Or you can use a stylus cleaning brush, or, a small camel-hair paint brush to dry-clean it, always pulling away from the stylus never side to side or backwards.  In severe cases you can apply a drop of pure, or nearly pure alcohol to the brush to clean off any greases or films.  I store some in a dropper bottle next to my turntable.  There have been some warnings about alcohol loosening glue in some styluses, so, caveat to you there.  I just go for it.  The magic eraser (melamine foam sponge) does seem to work very well.  Just be careful not to bend and mangle your delicate stylus.  Gentle handling is required.  The brush method is easier to be gentle with.  I'll leave you with some pictures.  It took me about an hour to wash 14 records.  Happy record playing!

Stay Clean

The best way to keep records clean long term is to wipe them down with a dry carbon fiber brush every time you play them.  Records collect new dust very quickly.  The best brush I have found is the Hunt EDA Mark 6 which is consistently $30 at any place you find it, but it's worth it.

Just spin the record on the record player, covering the surface with the brush, then clean the brush with the metal cover/stand by scraping the bristles with it, this will knock off all the debris.

KORG MONOTRIBE: separate outputs for SYNTH and DRUM

ALLLright.  Another mod for the amazing Monotribe.  I didn't want to bother with the separate drum outs / drum tone/decay mods that a lot of people are doing, because, the humbleness of the drum sounds is what they are, I am fine with them, I just wanted them coming out of their own jack.  That way I can run them through a reverb, an overdrive, whatever!  Without affecting the synth, or, vice versa.  Having separate outputs for each individual drum sound is tweaky and cool, but, I didn't see myself wanting that kind of commitment to all those cables and audio channels.  So yeah, just a drum jack and a synth jack for me.

Using my audio probe (you can google this) I located the VCA output, which is indicated in the pictures below.  It's the middle lug of the mini-pot that controls "VCA Level" on the front panel.  Likewise, I found that all the drums are mixed together at the middle lug of the pot that is labeled "RHYTHM" on the front panel, also pictured.

I carefully located and drilled for two 1/4" Neutrik jacks in pretty much the only place on the enclosure they would fit without running into other things.  Be very careful with this step, it would be easy to screw up.  First  I center punched with a center punch tool, then drilled a small pilot hole with a small bit, then enlarged it to the full size using a stepped unibit.

Pictured are a couple places I tried for grounding both jacks.  I thought I was getting noise from ground loops so I soldered a few different ground schemes.  Any of them should work fine.  It turns out that I had to add a 1 Megaohm resistor (slightly higher or lower value would probably work fine) from the tip of the VCA Out jack to ground.  Without this ground reference, I was getting some pretty ugly noise on the Drum Out jack.  I discovered the solution by flipping my VCO Mute switch (a mod I posted earlier on this blog), which killed the noise, so, I thought maybe adding a pulldown, or ground reference to the VCA jack would kind of do the same thing.  I got lucky and it did.  The synth will still make a few seconds of noise when being turned on sometimes, but, it fades away quickly for quiet split Synth/Drum use, and a nearly perfect mod!

The output is slightly quieter on the new separate output jacks, compared to the main standard output (which still works), but not by much.  The best part is, the volume controls for VCA Level and RHYTHM level work on the new jacks that were just added!  Nice.

I'm looking forward, now, to separate effects chains for the synth voice, and the drum voice.  The drum machine sounded really nice being run through a small guitar amp.

UPDATE:  It seems like the longer the monotribe sits, turned off, the more the noise "charges up" and needs to be bled away when turned on after a while of being off.  After a long sit, it takes as long as half a minute for the noise to fade, but, yes, it does fade and it still works fine.  So be aware of this if you do the mod.

UPDATE 2:  I added a 1M resistor to the drum jack also, tip to ground.  It seems to help a little bit with the noise, speeds up the time it takes to fade out, slightly.  I would recommend adding this resistor, also.  Sometimes the static noise will go on for 2 or 3 minutes before finally fading out, I've found, after sitting off over night.

UPDATE 3: Not being sure if these outputs are coming off a coupling capacitor or not, I added a 22 uF cap in series to each jack, (+) end to PCB, and (-) end to jack.  I also haven't heard that start up noise in a while.  Maybe it's solved now?  Maybe it was related to weak batteries I just changed?  Maybe it will come back?  Devil knows... These caps are recommended.  I think in my messings around I found that they made the synth not get screwed up when the drums are going out the separate jack, which was happening when the caps weren't there.

The quirk from the separate outputs mod is, if you use the drum output, the drum signal on the main stock Output jack goes way down.  The synth does not seem to be affected in this way.

Pictures for reference: