Dim C

[Gregg Hermetech]

i've had a DC-2 for a number of years and i love it. it's the best, most ethereal chorus i have ever heard.

they are very plentiful here in japan, but prices have been creeping up over the last few years. i bought mine used in a guitar shop for about 8,000 yen, but the going rate now is about 28,000. having said that they are very common here and i could pick one up any time.

i also had the digital space-d but didn't like it anywhere near as much, and so sold it.

when i use the dc-2 as an effects send with my mixer i have to attenuate the input a LOT to avoid distortion which i feel is definitely not musically pleasing the best/most pro way to do it would be with a reamp device and a dual di for level and impedence matching (plus the signals would also get to travel through 2 phat iron transformers!), and i will try this in the near future.

i would also be very interested in scott's dim c or something similar, which would easily integrate with my frac rack modular synth.

i've been looking out for a dimension d too, the going rate here seems to be anywhere between 40,000 - 80,000 yen, but i haven't manged to track one down yet, and they often look pretty beat up when i do see them.

[para]

here is a nice diy reamp. edcor and OEP make very good, clean and inexpensive trannies. the design is from a guy named NYDave that is on all the pro audio forums. he does great work


if anyone does a pcb run of either the C or D i'm in


steven

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[LWG]

Hello,

Count me in on this or a D. The clips on Scott's site sound good and the stereo ins are a big plus. I would like to echo a caveat about the C, in that
I also have one of the original stomp boxes that I've had since
(late 80's?), and the thing I noticed is that the headroom issue (being a major difference in the D and the C) is not too noticeable if you're using a digital/hybrid synth.
On the other hand, if you're using it with an analog polysynth, it is more noticeable (in my case, I used an OBX series synth). After testing it with
the analog, I generally kept it confined to use with an ESQ1.
I tended to favor the 1 and 3 settings, as 2 and 4 seem to make the fundamental swim a bit more. (1 is not an off position on mine; its the mildest chorus setting).
If your application for the box is use with analogs, I would humbly suggest
addressing the headroom issue.
In this sense, I would equally be on board to do a clone of the D, as the
stock design would probably be more accomodating of larger bandwidth
instruments.


Regards,


Lawrence

[Scott Stites]

Hey Lawrence,

A belated to you!

I've never had an original DC-2 to compare it to, but I think headroom has been helped out with the way I arranged the input structure of the Dim C. I lowered the input impedance to 100K and buffered that with an NE5532 (though at the time, it didn't occur to me that it would have been better to use 10K feedback resistors rather than 100K). The input attenuator makes all the difference in the world, too. I can run the DW6000 (dunno if that qualifies as an analog polysynth - guess it does if you take into account they're wavetable oscillators rather than VCOs, but the rest is analog) through it and get it adjusted for a decent recording level with none of the harsh overdriving. Depending on the voice, it takes a bit of twiddling, but generally it does pretty good.

When I use it with the modular, I usually put it at the end of the chain after the signal has been brought down to line level. It certainly wouldn't like 10V p-p signals.

I've only got three mode switches on mine, but it covers the original four modes of the DC-2 - in the original design, Mode 1 is all switches off, though the switch position of the built in switch of the DC-2 gives the impression that something is switched in. That position on the DC-2 actually switches everything "out". Since I used toggle switches, putting in a switch for mode 1 would have accomplished nothing - it doesn't switch anything in! So, that's why no mode switch in the "On' position is Mode 1 on the Dim C.

Take care,
Scott

[Scott Stites]

Subject veered off course into IP, which deserved its own thread. Split off to here:

http://electro-music.com/forum/topic-20942.html

Cheers,
Scott

[Randaleem]

Thank you Scott! That was very much needed.

Kind regards, Randal

[THeff]

There is a PCB design for the Dim C here:

http://topopiccione.atspace.com/PJ18BossDC2.html

I built a perfboard version of the Dim C, but have not tried the PCB.

Regards,

Tim

[dave_b]

[THeff]

Hey Dave,

Wow I completely missed your link to the Dim C pcb!

I was considering making one of the pcb's even though I perfboarded it earlier just because I like it so much.

I noticed that the CE-300 shows up on ebay periodically for a good price. From what I could see in both of the schematics is that it is a rack mount version of the DC-2 and the only difference is that it has two pots to setup the modulation instead of the switch.

Regards,

Tim

[zero the hero]

I've built the DC-2 using the PCB on my site, it was an hell of a job mainly due to the complexity of the schematic (and lack of experience... the whole board has been designed with Photoshop...): it's a jumper paradise, but once soldered it works well.
It's not noisy and I use this pedal regularly for gigging: it has become my favourite chorus so far.
I believe that the output mixing stage is a mess, since I used hard bypass (switches) instead of FETs so that this stage is not close to the original factory schematic. Scott's project is more faithful and I was going to ask him if I could update my PCB using his schematic... unfortunately I never did such a thing since I'm happy enough with this pedal...

[THeff]

Hi Zero the hero,

Wow I am amazed that you made that pcb design with Photoshop! That must have taken some time and effort I made the EH PolyPhase pcb from your web sight and was very pleased with the results. Since then I built JH's Tau Pipe Phaser which is pretty hard to beat. The envelope modulation of the PolyPhase is still cool though!

I still might build up the Dim C from your pcb one of these days

Regards,

Tim

[jfromel]

Hi All.....

I am a brand new member but I have been e-mailing back and forth with Scott in my build of a Dim-C clone. I have it finished now. I have made 4 of them and have enough boards to make 50 more. Scott suggested that I consider doing a PCB DIY kit but I really don't want to be bothered with the documentation right now and the PCB for the pedal requires vertial mounting of all resistors, the eyesight of an eagle, and mad soldering skills. I may do a rack version in the future with a larger layout but it is at least a year off.

Thanks Scott for all your help.

For anyone who wants to build one you will be happy in the end. The clone sounds way better than my original DC-2 due to better PCB design and higher quality components.

As far as IP goes I am ok with building this, the PCB design is 100% my work and if Roland still wanted to build this circuit again they could have. The DC-2 was never a hit and 30 years later the street price is still less than the original retail.

This build is true bypass, can have multiple modes, and it's not hot pink.

[StephenGiles]

That is a work of art you have there!

[Uncle Krunkus]

Is that an ExpressPCB? Or did you get them done by someone else?
I've been wanting to layout the DimC for a while, but couldn't be bothered if it were just for me as I don't have the cash to finance it. That, and IP worries.
Are you gonna sell any of the PCBs? I might get one or two if you are.

I s'pose then I'll be able to move on to the dual DM-1, or the STD1!

[Peake]

I'd buy two of those boards as well!

Here is someone who says they've had the 3207 remanufactured:

http://visualsound.net/bbd.htm

$3.75 each, but I don't see how to order except to phone in.

I may have posted in this forum about the 3207 being the low-voltage clone of the 3007. My mistake; that's a different prefix. Not being familiar with the innards of the Dimension C, I'd taken it that the 3007 was used there as well as in the Dimension D.

Uncle, do the STD-1! I've got an MN3011 waiting for your PCB I also have lots of photos of the populated board, both sides, and notes of the mods (caps and resistors tied together off-PCB, etc.) Note that the parts layout from A/DA Depot does not match the actual STD that I'd owned. One section is missing entirely. I have complete schemos and docs from A/DA themselves that might supercede the other stuff on the net (or may not). I'm happy to share it since they're out of business, and the design needs to LIVE!

Plenty of silver mica caps in that machine...

[jfromel]

Uncle - This was done with ExpressPCB, I will address the PCB issue below.

My next project will either be the elusive Dytronics CS-5 Tri-Stereo Chorus (Fulltone was working on it but has now scrapped it), or an analog and digital delay combo based on the DM-2 and a PT2399 delay for the digital side.

Peake - There are a few clones of the MN3207/MN3102 set out there, VisualSound has one branded but my guess is that it is either manufactured by CoolAudio or Shanghai Belling. My chips are NOS Panasonic MN3207/MN3101 from suppliers in China.

The MN3207/MN3102 in the Dim-C is the low volt version of the MN3007/MN3101 in the Dim-D.

The current set of boards was specifically designed to fit into a Hammond 1590BB enclosure and I was not really thinking of selling the boards for DIY at the time. As a result the part layout is nearly impossible to read because everything is packed in so tight and there is no documentation. I suppose I could do a version on a larger board with a less insane layout that could be used in a module or fit into a rack. If there is enough interest I will think about doing a run of them. Here is what I would want to know.

How much should I charge for the PCB's
Would you want a DIY kit that included the components? and how much should I sell that for?

If there is enough interest and it would be worth my time I will make a go of it when I get caught up on my other projects including filling the orders for the pedals, which I am selling for $279.

[Peake]

Thanks for your reply. Great work on that board, it's quite compact!!

I -thought- I was right about that. Would it be possible to use the actual 3007 for better headroom/SNR?

Folks here sell PCBs from $8.00 each to $50.00 and more, depending upon the project. Sounds like you're making a living on it so price accordingly, but of course, if that's so, people will expect full documentation and some hand-holding if they run into difficulty. A spacier board would be nice but I'm not scared of the small one, if there is a layout and wiring diagram to be made available. That's just me. I'm willing to help if I can.

Some folks offer a few levels when it comes to projects, depending upon the rarity and complexity. 1- PCB only. 2- PCB with rare/selected value components, if any. 3- PCB and full parts kit. Bridechamber.com offer PCBs as well as various single components and full parts kits for some projects, as well as front panels and completed modules. A couple of other folks here do as well.

Well done!

[Uncle Krunkus]

No, don't do a different board. I'd be quite happy working with the cramped one. Component layout doesn't worry me, as I'd just work it out as I go along. I wouldn't want components either, as I've got heaps, including the 3207&3201.
I just thought it would be good to take a board or two off your hands if you're not using them for anything else.

[jfromel]

Peake: The power req's are different for the 3007, I think that you could use it but the 3007 needs -14 V to run but the 3207 will work with anything between 4-10 V, if you look at the application schematic for both they are nearly identical. Perhaps Scott could chime in here as I have never worked with the 3007.

Botique builders that use the 3007 claim it has more headroom. Analogman uses the 3007 in their chorus. Since I am using this for a guitar I have more than enough headroom, but it is a pedal. Scott has said that his rack unit has plenty of headroom.

Uncle: Let me get my orders complete and if I get sick of building these I will sell you a couple of boards.

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[mono-poly]

I would be interested in a board.
Small or bigger version.

[sneakthief]

yeah, i'd take a board too! small is fine... a high-res picture of the components directly above the board would make things relatively easy (in conjunction with the original schematics).

[Peake]

Don't forget that I asked nicely as well

Obviously, if you sell it, we will buy.

[jfromel]

How Important would stereo input be? I am about done with the PCB and Schem for a version with stereo input. I did not incorporate an input buffer but I suppose I could without too much hassle.

[StephenGiles]

I see that we are "addressing issues" here. I deal with problems

[kokoon]

interested in two boards, or even better - two full kits.

stereo input would be really really nice.