Rat mods?

[siaoguitar]

does anyone knows what goes on in the 3ways rat mod?
how to do this mod?

http://www.robertkeeley.com/product.php?id=7

i m going to build my rat, hope to incorporate this inside my rat..yahoo!!

[Mark Hammer]

This is complete speculation but given that the website blurb goes on about the marriage of a Tube Screamer and Clean Boost, my guess is that one of the switch positions will be simply lifting the diodes from ground.

Because the 3-postion toggle is limited in what it can do, the possibilities are somewhat narrowed down.  Use of a SPDT 3-way switch means that in the centre, something is not connected, and on the side positions one thing is connected or the other one is.  There ARE some switches that go A/Both/B, and some DPDT toggles that in the middle position leave A on for one set of contacts and B on for the other, but they are cumbersome to wire in such a confined space.  As such it is more than likely that the mod lifts the diodes out of circuit in the centre position, and connects two different sets of diodes (e.g., a pair of 1N4148 vs a pair of LEDs, or a pair of 1N4148 vs a 2+1 configuration of 1N34, etc) to ground in each of the side positions.   Again, I have no insider knowledge, just guessing.

[Samuel]

One position is stock (with a little bass response added because of the caps we change). A second position is what we call Phat Rat, it is thicker, has more harmonics, a tiny bit less distortion and more volume output. The middle switch position is what we call Mighty Mouse! Tons of volume output! This is a clean boost, with a lot less distortion; this is perfect for driving amps into natural overdrive.

I would also not be surprised if in addition to the diode lift, one of the positions swaps in an alternate diode type (LEDs perhaps, since these are used in the Turbo Rat). That would account for the "lower distortion, more output" mentioned above.

[Nasse]

http://www.muzique.com/ebook.htm

[strungout]

(edited, but rat mods link still good)

http://www.diystompboxes.com/pedals/ratmod.gif

[Mark Hammer]

It would be a mistake to think that people who have a good reputation and commercial operation for providing mods are doing something that only the annointed ones could ever think of and perform, just as it would be a mistake to think that they don't cruise these forums looking for good ideas that might appeal to a lot of people.  It would be a similar mistake to think that a bunch of people could not "think up" similar mods to a simple design on their own in isolation from each other.

I'm certain that many of the mods-for-fee people often see advertised are fairly simple and straightforward component changes that forums suggest would appeal to enough people to make it worth someone's while to advertise and price in a sustainable fashion.  At the same time, a lot of the folks who might like such a mod are unable to identify what end of a soldering iron to plug into the wall or are simply too pressed for time to acquire the chops to do it themselves.  The people who do the mods aren't ripping anyone off, but that doesn't mean the mods are rocket science that others with a bit of basic know how couldn't stumble onto themselves.   It's not like we're talking about a 3rd party firmware update to a synth workstation.

[strungout]

I'm stupid and I should makes sure I read everything when I'm giving my opinion:

If you look further down the keeley rat mod page, youll find a .pdf manual which says exactly what they do to the pedal: add one diode, for more tube-type tone, and take out one, for more output.

 :x :oops:  :roll:  :lol:  

[Mark Hammer]

If it makes you feel any better, you're not the only guy who didn't read that.   :oops:

[siaoguitar]

yo..yo, mark, wah, so agitated? Sori, what u trying to say?
so u for modding ourselves or u on the other side?

[Mark Hammer]

Both.  People who CAN do it themselves should.  But people who can do it for themselves have a tendency to look at sites like Keeley's and mumble "Fifty bucks?  For that?".  My point is that just because it gets advertised as some fabulous mod does not mean it isn't something you couldn't think up yourself, and conversely just because it's something you could think up yourself doesn't mean that other people could too, or that they could do it themselves.

My post is a pre-emptive strike.  Typically, when the basic nature of a commercially offered mod seems, well, BASIC, somebody will invariably complain about how unglamorous it is for the price asked.

[petemoore]

Bread board on which you can build any 'normal' parts count circuit on, and buy the parts for a reasonable circuit+ mods for parts? How much...
 It's good for the modderz that these things could be connected to dangerous potentials of voltage...
 Many folks just don't want to take the risk, don't have the time, inclination for stompboxes...and the:"I have all that built into my amp 'syndrome" no sense of adventure combined with lack of faith in ones abilities...it does take time to develop chops, if you don't have screwdriver and pliers you're looking at 100$+ to even make it worth starting, but for those who 'dare' there are chops 'o plenty in color by number format....er that's what it looks like to me 'now' ...3 years ago I started putting FF parts on a piece of hardback cardboard...ok...this little part with the three orange rings goes here, there and to the battery and this yellow purple brown...NO...[three days later] that ones yellow purple RED!!! akkk...back to the store.
 Then there's the question "Am I actually a better player or entertainer since I geeked out on the electronics?"...I just go by what they tell me.
 I'ts not uncommon to have a guitar player whos'e read of electrocutions on stage, and think potentially lethal voltages exist in stompboxes..."Isn't that dangerous?"
 I figure if I'd been earning money werkin' with the amount of time I've put into effects building. subtract the expense or savings over buying made ones...I'd be spending alot of time not doing what I like to do...probly have more money to throw around...commercial effects seem not too hard to sell for 1/3 to 1/2 of investment...probably better if you do your shopping studies...I don't think there's any way I'd have the low noise floor and wide pallete of nicely tuned tones that I have today...I like knowing about the stuff, and repairs start adding up more frequently [my stuff and others]...and the important question: "Would I ever have had my amps input custom modded...try 'this' cap there..." ... No...It needed done real bad for the first six years I've had it, I just didn't know it.

[ocelot]

I was needing a RAT and in OZ they don't pop up much. Anyway I opened the RAT had a look There is the basic cap upgrades a metal can opamp.There is hot melt glue over the mod but there is a 5mm LED in there and all I can see is that the switch switches between different diode combinations. I personally found the pedal quite unusable I emailed keely and asked for some help as the Pots can oly be used between 0-2 there is too much gain. He didn't respond he is a wanker You can get some good AC/DC sounds. However I changed the distortion pot to a different taper. I wouldn't buy a keeley again.

Cheers

Anyone want to buy it ?

[Toney]

Thats harsh, ocelot.
What kind of guitar/amp/style of music? I often find that a pedal may be av. with one combo, but have unique and great tones with another.
Try a "turbo"(ha!) od2 with a tele.....sounds great, but sucketh bigtime with 'buckers.
If you're in Melbourne, go to music swap shop...they have everything old and new AND, you can trade that RAT...for an original if you like.
If you're into buying pre modded pedals....you should check out Analogueman's take on the humble SD1 sounded outstanding on his site.
Otherwise.........build your own!!

[WGTP]

Check out Tonda's Rat Mods in shematics section.  Also, adding a single or double LED to the feedback look is cool.  Changing diodes will make a much more noticeable difference than higher quality caps or resistors.



Under Pro Co Multi-Rat

http://www.diystompboxes.com/pedals/ratmod.gif

[siaoguitar]

Hi to al, i would like to do the 3-way mod, may i know what kind of 3way toggle switch should i get?,
how many contacts at the bottom of the switch?

[WGTP]

Check out the thread about 3 way diode switching.  You guys are talking about the same thing.  The Dod 250, Distortion +, Rat, Boss Ds-1 and many others all have the same diode to ground clipping set up.  I have seen plans for 6 way switches for these type distortions.  Many posibilities using SI, GE, Jfet, LED, etc.  

[StephenGiles]

All you need to do is change the 47 ohm resistor to a 1 ohm.......need I say more!!!!
Stephen

[Mark Hammer]

Hi to al, i would like to do the 3-way mod, may i know what kind of 3way toggle switch should i get?,
how many contacts at the bottom of the switch?

You need a SPDT on-off-on toggle.  This has two side lugs and a common in the middle.  When in the centre position, the common does not contact either of the side lugs.  Switched to either side position, it will connect with the lug opposite to where the handle is leaning (i.e., if the handle points to outside lug A, then the common connects to outside lug B).  A DPDT on-off-on switch will also work just fine if you can't find the other one, except that it will probably be a bit more expensive and you only need one set of contacts.

Place you different diode sets on the board, and run a wire from the free ends of the diodes to one of the outside lugs.  Then run a lead from the common of the switch to ground.  This way, either diode set A connects to ground, diode set B connects, or neither connect.

[siaoguitar]

Hi Mark, can i still use mine with 6 terminals? so it is a dp3t? coz it is 3way with 6 contacts below.