MT-32 revision guide

[Alistair]

Hey folks,

Just wondering what the different revisions actually mean. No idea what my personal one is (don't see it for another week now), but the new one I got is v 1.07. Apparently Frank's is 1.04. Someone help me out here.

- Alistair

[Cloudschatze]

This is on my list of things to compile, but for now...

Software changes:

Ver. 1.04 to 1.05

Changed the VOLUME-control taper by changing the ROM programs.
Result: Smoother volume change in response to a VOLUME setting change.

Ver. 1.05 to 1.06

Added a reset to the rhythm section Bender Control when A11 Parameter Reset (MIDI) is received or Active Sensing is not received.

Displays will not change, even when a Display Change exclusive MIDI message is recognized, unless the current mode is Master Volume input mode (e.g. Power-up default).

Ver. 1.06 to 1.07

(Unspecified ROM changes, related to the mainboard changes)

For stable program operation.
If the program won't start after replacing SRAM, use ROMs of Ver. 1.07.


Hardware changes to 1.07 ROM units:

LA32 chip - From 80-pin PGA to 100-pin flat package.
LA Program ROMs A/B - From EP Rom to Mask ROM.
Reverb Program ROM - From 128k EP ROM to 256k Mask ROM.
WAVE ROM - From two 2M ROMs to one 4M ROM.


Most of the 1.07 units should include minor modifications to the LCD display as well, consisting of some sort of static-discharge mask, and grounding of the LCD frame.

Hrm... Looks like the gate array was changed too.

[Alistair]

So, amongst the other stuff, the 1.07 should sound better and be slightly improved over previous versions?

-Alistair

[Cloudschatze]

It may sound a bit different, depending on what was changed in the reverb program, and how the volume changes are used. Nothing was done to actually make the MT-32 sound better though until the 2.xx ROM releases.

[MusicallyInspired]

How do you check the version on your MT-32 again?

[Dustin]

How do you check the version on your MT-32 again?

Press...
[PART 4] + [RHYTHM] + [MASTER VOLUME]
...then Power Up.

[glendower]

{places cover back on MT-32} :oops:

[mratzloff]

Sorry for such an old bump, but I'm trying to buy an MT-32 and would like a little guidance on how to determine the generation.  I already own an SC-55mkII, which was much easier to determine since the generation is right there in the name.  :-)

Barring finding a Real World Interfaces mod, it sounds like I want a third-generation model for the best sound.  I know that second- and third-generation models have the headphone jack, but it appears from pictures that some have angled fronts (wedge-shaped) and others are square (box-shaped).  Is that right?  If so, which generation is which?

Also, can someone post pictures of the different revisions?  Maybe we can put together a buying guide for people like me.

[NewRisingSUn]

There is no third-generation MT-32. The only third generation modules are the CM-32LN and the CM-500. And you don't want the third generation for its annoying vibrato.

Best module to get is the CM-32L --- cleanest sound of all modules, compatible with all games, no hassles.

[mratzloff]

Oh, I was going off of the Wikipedia article, which mentions a third generation, but I see it is talking about "MT-32 technology", not the MT-32 itself.

http://en.wikipedia.org/wiki/Roland_MT-32#Models

Maybe I'll get both an MT-32 and a CM-32L, but I'll admit I'm not a huge fan of the appearance of the CM-32L and the yellowed plastic (after 20 years).

[Laust]

I think all MT-32s are wedge shaped? if they look different, it's probably due to the angle, the photo was taken from...

[Great Hierophant]

but I'll admit I'm not a huge fan of the appearance of the CM-32L and the yellowed plastic (after 20 years).

You need some Retr0bright to clear away that yellowing:

http://retr0bright.wikispaces.com/

[Cloudschatze]

Best module to get is the CM-32L --- cleanest sound of all modules...

I suspect that the "newtype" MT-32 and CM-32 are probably equal, as far as clean sound is concerned. I've never owned a CM-32 to do a side-by-side comparison, alas.

I haven't used them in a while, but I actually recall the CM-500 and CM-32LN sounding cleanest to my ears...

[jharris01]

Sorry for such an old bump, but I'm trying to buy an MT-32 and would like a little guidance on how to determine the generation.

Ask the seller for a serial number. The wikipedia article can help you determine which revision model is being sold.

[mratzloff]

Thanks, everyone.  Great advice.

[NewRisingSUn]

I haven't used them in a while, but I actually recall the CM-500 and CM-32LN sounding cleanest to my ears...

The CM-500 has a high noise floor because of the combined GM/LA engines. The CM-32LN is indeed even cleaner than the CM-32L, but is only available in Japan and most importantly it has the Parkinson vibrato.

[Cloudschatze]

The CM-500 has a high noise floor because of the combined GM/LA engines.

Good call. I'm not sure that this is a huge concern (given all of the other factors that affect the output in a signal chain), but I did a couple of quick, subjective tests between the modules I have, and as far as noise floor is concerned, they rank as follows (from best to worst):

• CM-32LN / MT-32 Rev. 01 ("newtype")

• CM-64 - Only slightly noisier than the preceeding modules.

• CM-500

• MT-32 Rev. 00 and 01 ("oldtype") - Worst of the bunch, not to mention the constant, high-pitched whine...

How does the CM-64's noise floor compare to that of the CM-32?


Speaking of sound quality, I noticed that the "newtype" MT-32 I sent Alistair sounded flat-out better than the other two I have, with regard to the openness and depth of the soundstage. All of the components, ROM levels, etc. were exactly the same between the units. The difference - my two mainboards have seen fewer than ten hours of use since manufacture. I'm not sure that I believe in the so-called "DAC burn-in" effect, but there definitely seems to be some sort of component settling that occurs through extended use.

[endre1952]

My CM-32L indeed sounds quite clean compared to my CM-500. I've got a CM-64 also, but have not listened to it much.

I fail to see why some people consider an MT-32 the perfect solution. As far as I'm concerned, it's only good for games made by Sierra (minus LSL5, which takes advantage of the sound effects found in later models).

[Cloudschatze]

I fail to see why some people consider an MT-32 the perfect solution.

Well, since no single module is capable of playing-back everything as intended, the "perfect solution" becomes a matter of personal preference and acceptable limitations. So, while it sounds like the CM-32L works well for you, someone else's solution might include two 1st-gen MT-32 units in a split MIDI-channel configuration, two 2nd-gen MT-32 units in an overflow-assigned configuration, and an LAPC-I... 

[NewRisingSUn]

CM-32LN / MT-32 Rev. 01 ("newtype")

The CM-32L fits in there as well; the DAC linearity error mentioned in the Wikipedia article seems to be audible only in contrived cases.

CM-500

• MT-32 Rev. 00 and 01 ("oldtype") - Worst of the bunch, not to mention the constant, high-pitched whine...

I would think that minus the whine, the old-type MT-32 has actually a lower noise floor than the CM-500. The whine by the way is the SH1-3 signal fed into the demultiplexer that somehow creeps into the output.

How does the CM-64's noise floor compare to that of the CM-32?

Higher. Not as high as the CM-500's though.

Speaking of sound quality, I noticed that the "newtype" MT-32 I sent Alistair sounded flat-out better than the other two I have, with regard to the openness and depth of the soundstage.

It would be great if you had recorded the output, so we could analyze what "openness" and "depth" means technically with regards to the frequency spectrum. I suspect that its low-pass filters for some reason attenuate more of the high-frequency information, which is usually perceived as more "open"/"warm"/"deep". For example, many commercial recordings sound more pleasing to my ears if I apply a modified X-curve (attenuating 3 dB per octave starting at 4 kHz)

Well, since no single module is capable of playing-back everything as intended

I haven't spent much time editing MT-32 timbres, but would it be possible to modify the instruments that sound different on the CM-32L to sound correctly on all modules? You mentioned in the past something about which parameters they were. The instruments affected to my knowledge are "SpaceAlvin" (SQ1), "TakeOff MS" (SQ3), "Whiporill" (KQ5) and "Acou BD" (PQ2).