Beefing up Micromoog sound

[Voyager777]

Sorry if this is a frequently posted question.

I notice that many in the synthesizer community feel that the Micromoog, along with the Multimoog, has an inferior sound compared to other Moogs.

Can anyone attest to the effect of this filter mod? http://www.emusic-diy.org/MoogManuals/MicroMoog

I was wondering if this mod would bring the Micromoog or Multimoog much closer to the sound of say, a Rogue or Prodigy, even though it is still lacking a second oscillator.

Also, how would you say the Multimoog compares with the Prodigy?

[museslave]

I think the notion that Micromoogs are thin is a subjective rumour. I was able to get very nice, broad, and "Moog" sounding timbres from mine with very little effort, as demonstrated in my YouTube video.
KL has indicated that the Micro was slightly overdriven to give it a warmer sound, which differentiates it from the Multi...
I really believe that the Micro- Rogue, etc. comparisons are more to do with the lack of a second osc than a fatness problem. In addition, it's just a timbre difference.

The Sonic Six, in comparison to all of them, actually DOES have a "thin" sound.

[LWG]

Hello,

The thing the mod points to is that the way in which a synth's stages are coupled together can shave off a region of frequencies, depending on component values.
This was not uncommon, in that it also occurred on the Arp Odyssey and Oberheim OB-8.
The addition of greater capacitance in this case restores some low end that gets shaved off when just the stock capacitance value is present.
It may be a bit problematic comparing it to a two-osc synth like Rogue, as
the addition of a second oscillator provides more animation and depth to the sound, but not necessarily punch.


Regards,


Lawrence

[Kevin Lightner]

This is touchy territory here because both myself and MC are on this forum.

My feelings are that Moog designed it a certain way for a reason.
I tend to go for stock, then modify the sound afterwards.

Installing a large capacitor will create a higher average DC level on squarewaves.
Put simply, it will thump.
That might be better sounding to you though.
When the Micro was designed, there wasn't the types of music there is now.
Cars didn't go thumping down the road.

So, it might work for you, but there's a lot to be said for having 2 or 3 VCOs.

[Voyager777]

I tend to go for stock, then modify the sound afterwards.

Sorry I'm kind of new to all of this.

I know many people add things like audio inputs and MIDI, but is it possible to add an extra oscillator? Or is there simply not enough room?

I know if I wanted a second osc I should just look into getting a Prodigy or Multimoog instead, but I'm just obsessed with the Micro's ribbon controller and small form factor.

[Kevin Lightner]

It's possible to add a second or even third VCO to a micro, but it raises a lot of questions.

If a pro does it, can you afford it?
If an amatuer does it, can you afford any problems?

Where would controls be placed and what would they be?

When you start adding up all the controls you'd probably want, the idea can get out of hand: waveform? pitch coarse or range? fine tuning, hard sync?, env modulation for the hard sync?, volume?

The most minimal mod like this would be one tuning control with limited range of an octave higher or lower and a pre-chosen waveform like sawtooth or square.
Then, everything the first VCO does, so would the second.

There is room and enough power to drive one or two.
I just don't recommend doing the mod unless you yourself have the experience or the money to pay someone that does.
Could get messy.

[Voyager777]

I know just the right guy,

Thanks.

[LWG]

Hello,

Since I just recently noticed the Micro mod myself, and haven’t had a the opportunity to play with one that had the mod, I was unaware it presented the dc thump however, I have had the
opportunity to play others that had been altered, and they seemed to have improved response without changing the overall character of the synth.
With regards to the oscillators (and this refers to 777's question of going from Micro to Prodigy/Rogue), more are certainly useful and provide a bunch of other options
such as tuning to intervals, doubling, octaves, audio-rate mod, but this assumes there is no qualitative difference between the sound of the machine with one oscillator and the one with more than one.
Is a Mono/Poly better because it has more oscillators than the Mini D? Is an EML-101 better than an Odyssey because it has two more oscillators? As previously stated, there are an additional set of options presented with more generators, but thats quantitative. Perhaps the machine with less osc has a sound quality that has a bit more substance. If this is the case, is more better? I don’t know, but these things tend to end up being determined by the user and what they value.
Also, for 777, if you must upgrade from the Micro, you may want to look at an LP Stage.
At this point, a Prodigy thats been serviced will go for a pretty good price. Saving a few pennies for a LP might not be a bad idea.


Regards,


Lawrence

[eric coleridge]

I'd like to chime in hear because I've owned both a Micro, and Multi at different times. I've also performed the VCF mod on the Multi, but not the Micro.

I point out my experience with both because although these synths obviously have very similar circuits, and similar architectures, I think they have a fairly different sound from one another.

One thing that stands out to me with both is they have poorly implemented envelopes. Even though many Moogs suffer from a lack of ADSRs, it seemed especially apparent on the Micro/Multi for some reason. Maybe the attacks are a little slower than others...

I personally like the Micro's sound better (although it's still by no means the best sounding Moog). The second oscillator on the Multi doesn't add much to thicken it's tone, and counter-intuitively, to me, actually makes it sound thinner. Something about the way the two oscillators mix (with only one cross-fade knob) seems to detract from the synths overall punch.

The Micro sounds more raw than the Multi, IMO. I liked it better. The Multi has alot of very useful and unique features, but it's sound is not too animated or inspiring. The Micro is a little better.

Also I found the modification to be disagreeable to the overall sound of the Multi. I definitely noticed that it improved the bass response of the knob: On both synths, in stock shape, the filter doesn't really start to open up much until mid position on the dial. Alot of people seem to find this to be a problem. I have to admit that I didn't particularly like this response myself.
After you perform the mod, the cut-off has a more typical response, opening up closer to the first quarter turn of the knob-- but it also seemed to both draw out and lengthen the response curve at the other end of the cutoff frequency (which I didn't like at all), and exaggerate this weedy kind of tone in the higher frequencies (which I liked even less).
I don't understand the mathmatics in regard to capacitence and this changed cutoff response curve, but I didn't like it---and I didn't think that the "improvement" in the low end justified the drawbacks to the higher end frequencies. I suspect that whoever discovered this improvement may have done so with the help of an oscilliscope, and without the consoltation of his ears. But that's just my opinion.

Both of these synths are designed with audio inputs to their filter, and really good facilities for interacting with external equipment. So you really wouldn't need to install any additional oscillators. You can just patch them in. These synths were made to be used in conjunction with other Micros, Multis, external oscillators, etc. All you have to do is just plug them in.
For instance, you could just get one of these new Mooger VCOs, and you'd have a pretty good dual oscillator synth.
Another great stock feature of the Micro (but not the Multi for some reason) is it's ability to output the raw oscillator signal for external processing. This makes it quite useful if you wanted to mix it externally with another oscillator, and then inject this mix signal back into the filter.

Even so-- after all this, in some respects, you might still be better off with a Rogue.

[Voyager777]

Thanks for everyones help. This forum offers quite a bit of knowledge and experience, which is much obliged.

[MC]

After you perform the mod, the cut-off has a more typical response, opening up closer to the first quarter turn of the knob-- but it also seemed to both draw out and lengthen the response curve at the other end of the cutoff frequency (which I didn't like at all), and exaggerate this weedy kind of tone in the higher frequencies (which I liked even less).
... I suspect that whoever discovered this improvement may have done so with the help of an oscilliscope, and without the consoltation of his ears. But that's just my opinion.

I designed the mod on the Micromoog. I didn't have access to a Multimoog but both model share the same master synth board - VCO-VCF-VCA-EGs-LFO so I saw no reason it wouldn't work on the Multimoog. When I tested it out on my Micro (using my ears, not the scope) it did not exhibit the behavior you found on your Multi, and it should have not affected it in this manner. I suspect that something is malfunctioning in your VCF circuit, likely a leaky transistor.

Another great stock feature of the Micro (but not the Multi for some reason) is it's ability to output the raw oscillator signal for external processing.

I don't recall that feature on the Micro/Multimoog...

[eric coleridge]

When I tested it out on my Micro (using my ears, not the scope) it did not exhibit the behavior you found on your Multi, and it should have not affected it in this manner. I suspect that something is malfunctioning in your VCF circuit, likely a leaky transistor....

I don't think there was a problem with my Multi. But I think it's very possible that your mod might work better on the Micro. Mr Lightner, and probably you also, have remarked on this forum and others that the signal gain to the Micro's filter is different from that on the Multi--and I'd guess that this difference alone might change the response that the Multi exhibits in regard to your modification.

I apologize for my comment about your ears. I didn't take into account that your modification was designed or intended for just the Micro--and may not be suitable for the Multi. Then again, I've read that others who have performed your mod on their Multis did find a marked improvement.

But, it didn't agree with me. I did hear an improved bass response, but it came with a loss in other areas--- so I didn't find it to be a net gain.

Another great stock feature of the Micro (but not the Multi for some reason) is it's ability to output the raw oscillator signal for external processing.

I don't recall that feature on the Micro/Multimoog...

If you look at the user manual for the Micro, in the "Open System," or whatever it's called, chapter, it describes this feature. The raw oscillator (plus the sub, I believe) are output from the same 1/4" jack that's used for external signal input. It's a stereo jack: ext. in, osc out.
This feature, I think, could be particularly useful with the oscillator bypass switch engaged so that you can externally process the Oscillator+Sub signal and then inject it back into the filter without having to mix it with the internal oscillator signal.

Another less well known (I would think) feature on the Micro and Multi is their ability to output modulation CV, such as LFOs, Sample and Hold, etc. Unfortunately this signal is output to a 3/16ths" jack, a very uncommon standard. But if you can find an adapter to 1/4", it's a pretty cool feature.
In alot of ways, the Micro and Multi are almost on the level of patchability as the semi-modular Korg MS or Roland System 100.

The Multi even has After-touch CV and Ribbon CV outputs, and notwithstanding it's S-trig gate, makes an excellent modular synth controller.

Sorry to go on and on about these two synths, but they've been favorites of mine for a long time. If only they sounded better (particularly the Multi).

[MC]

I've also read of other folks who had success with the mod on the Multimoog - yours is the exception.

I don't have the user manual, but I don't know how many times I have studied the schematic and missed that feature on the ext in jack.

Yes that MODULATION jack is designed for a passive attenuator (such as a sweep pedal) but you could indeed patch its output to good use. And just replace that stereo 3/16" jack with a stereo 1/4" jack to make it much more useful.

The Micro/Multimoog are indeed practical instruments. The only drawback of the Multimoog is you can't sweep the hard sync'd VCO very far, there is little over an octave sweep and it's not enough. I was gassing for a Multimoog for a while but it would be redundant with my Voyager.

[eric coleridge]

I was gassing for a Multimoog for a while but it would be redundant with my Voyager.

Yeah, I think mostly because of their rarity, they seem to sell for a lot more than other vintage synths at their feature level. Although, it's difficult to compare them to many other synths, just because of all the really unusual features they have (aftertouch, ribbon, 2-mod bus, semi-modular--similar to the Voyager really). Plus they're extremely well constructed, in my experience. They have a very solid build and proffessional feel-- (much) more so than the micro. But for $1500? I'm not sure if they're worth it.

I was extremely lucky to find one last year in nearly mint condition for $400. I really liked most everything about the multi---except the sound. Had to sell it. I'm not a vintage synth collector, and can't afford to keep a synth that I can't play with. Oh well.

But it's crazy how much synth prices fluctuate. For reasons I won't go into, I bought an Odyssey, Sonic Six, and Multi last year and then eventually sold them. I payed arould $1500 for them all together and sold them for more than twise that. But if I had them today, I could probably sell them for $1500 each! At least. That seems very strange to me.

[yoshi]

A few years ago I purchased a micromoog on craigslist that had been modded with two extra oscillators, a normal/slow/fast speed switch for the lfo, and hard sync for the extra oscillators. The new oscillators sound much fatter than the original. I have no idea who did the original mod but the synth is now a total beast.