Hello guys,

I have just purchased a Roland SCD-70, because I wanted to do some high-quality game soundtrack recordings. The SCD-70 to my knowledge is the only Sound Canvas that is backwards-compatible with the SC-55 and has a higher sampling rate of 44.1/48 khz combined with a digital out. So I thought it would make a good candidate to do some clean recordings.

Now concerning the different instrument maps...

The manual states the following:

[2] Control change 32 value: MIDI bank number lower byte 0: use the INST MAP setting, 1: SC-55 map, 2: SC-88 map, 3: SC-88Pro ma […]
Show full quote

[2] Control change 32 value: MIDI bank number lower byte
0: use the INST MAP setting,
1: SC-55 map,
2: SC-88 map,
3: SC-88Pro map,
4: SC-8820 map)

So a value of zero is supposed to use the so called "INST MAP" setting and it also is the default. Moreover in the MIDI implementation documentation on the accompanying CD-ROM it says:

The SC-D70 recognizes the Bank Select LSB (Controller number 32) as a flag for switching between the SC-55MAP, the SC-88MAP, the SC-88ProMAP, and the SC-8820MAP. With a Bank Select LSB of 00H, the map selected by the front panel INST MAP button will be selected. With an LSB of 01H ... [and so on]

I was wondering, what button are they talking about? There is no INST MAP button on this device or is there?

Am I overlooking something?

Thanks

Here are the system exclusive messages to change the sound maps of the SCD-70. You can transmit them using a any Sysex program like Borne SendSX. Just copy paste the respective segements and send. The great thing about this sysex is that it will not revert to the default SC-8820 map even if your game or midi player sends a GM or GS reset. You can use SC-8820 sysex to revert back to default or reboot your module

SC-55
F0 41 10 42 12 40 41 01 01 7D F7
F0 41 10 42 12 40 42 01 01 7C F7
F0 41 10 42 12 40 43 01 01 7B F7
F0 41 10 42 12 40 44 01 01 7A F7
F0 41 10 42 12 40 45 01 01 79 F7
F0 41 10 42 12 40 46 01 01 78 F7
F0 41 10 42 12 40 47 01 01 77 F7
F0 41 10 42 12 40 48 01 01 76 F7
F0 41 10 42 12 40 49 01 01 75 F7
F0 41 10 42 12 40 40 01 01 7E F7
F0 41 10 42 12 40 4A 01 01 74 F7
F0 41 10 42 12 40 4B 01 01 73 F7
F0 41 10 42 12 40 4C 01 01 72 F7
F0 41 10 42 12 40 4D 01 01 71 F7
F0 41 10 42 12 40 4E 01 01 70 F7
F0 41 10 42 12 40 4F 01 01 6F F7

SC-88

f0 41 10 42 12 40 41 01 02 7c f7
f0 41 10 42 12 40 42 01 02 7b f7
f0 41 10 42 12 40 43 01 02 7a f7
f0 41 10 42 12 40 44 01 02 79 f7
f0 41 10 42 12 40 45 01 02 78 f7
f0 41 10 42 12 40 46 01 02 77 f7
f0 41 10 42 12 40 47 01 02 76 f7
f0 41 10 42 12 40 48 01 02 75 f7
f0 41 10 42 12 40 49 01 02 74 f7
f0 41 10 42 12 40 40 01 02 7d f7
f0 41 10 42 12 40 4a 01 02 73 f7
f0 41 10 42 12 40 4b 01 02 72 f7
f0 41 10 42 12 40 4c 01 02 71 f7
f0 41 10 42 12 40 4d 01 02 70 f7
f0 41 10 42 12 40 4e 01 02 6f f7
f0 41 10 42 12 40 4f 01 02 6e f7

SC-88 Pro

f0 41 10 42 12 40 41 01 03 7b f7
f0 41 10 42 12 40 42 01 03 7a f7
f0 41 10 42 12 40 43 01 03 79 f7
f0 41 10 42 12 40 44 01 03 78 f7
f0 41 10 42 12 40 45 01 03 77 f7
f0 41 10 42 12 40 46 01 03 76 f7
f0 41 10 42 12 40 47 01 03 75 f7
f0 41 10 42 12 40 48 01 03 74 f7
f0 41 10 42 12 40 49 01 03 73 f7
f0 41 10 42 12 40 40 01 03 7c f7
f0 41 10 42 12 40 4a 01 03 72 f7
f0 41 10 42 12 40 4b 01 03 71 f7
f0 41 10 42 12 40 4c 01 03 70 f7
f0 41 10 42 12 40 4d 01 03 6f f7
f0 41 10 42 12 40 4e 01 03 6e f7
f0 41 10 42 12 40 4f 01 03 6d f7

SC-8820 -Default Map

F0 41 10 42 12 40 41 01 04 7A F7
F0 41 10 42 12 40 42 01 04 79 F7
F0 41 10 42 12 40 43 01 04 78 F7
F0 41 10 42 12 40 44 01 04 77 F7
F0 41 10 42 12 40 45 01 04 76 F7
F0 41 10 42 12 40 46 01 04 75 F7
F0 41 10 42 12 40 47 01 04 74 F7
F0 41 10 42 12 40 48 01 04 73 F7
F0 41 10 42 12 40 49 01 04 72 F7
F0 41 10 42 12 40 40 01 04 7B F7
F0 41 10 42 12 40 4A 01 04 71 F7
F0 41 10 42 12 40 4B 01 04 70 F7
F0 41 10 42 12 40 4C 01 04 6F F7
F0 41 10 42 12 40 4D 01 04 6E F7
F0 41 10 42 12 40 4E 01 04 6D F7
F0 41 10 42 12 40 4F 01 04 6C F7

I like the SC-D70, it should make for a good Dosbox setup with PCM and synth output mixed in together and available on the headphone jack . Add an MT-32 to the MIDI out on the SC-D70 and loop the MT-32 analogue audio out back into the SC-D70 and you've got a compact complete setup without the need for a mixer or even an internal soundcard .

Thanks Bevil for the messages. Can you elaborate how the SYSEX works which you posted and where you got it from?

I suppose there are 16 different messages for each channel?

As you rightly surmised each line of message is for each channel . I generated it based on information from the SCD-70 midi implementation chart . This chart is only found in the Appendix file in the accompanying cdrom. It's quite technical and took me a while to figure it out.

Using this line of SYSEX which sets the map to SC-55 on channel 1 as an example
F0 41 10 42 12 40 41 01 01 7D F7

F0 -- Denotes start of sysex message
41 10 42 12 --- This is the identifer code for the SCD-70 , This does not change
40 -- The MSB of the address space (fixed value)
41 -- This represents channel 1.. Valid values are from 41 to 4F where 4F is channel 16
01 -- This is the action parameter which signifies tone map change. (Also the LSB of the address)
01 -- This is data value for the map itself. (01 for SC-55, 02 for SC88, 03 for SC88Pro and 04 for SC8820)
7D -- This value here is the checksum (computed by 128 - [(sumOfAddress+dataValue)% 128]
F7 - Denotes end of the sysex message

Bevil, that's a great explanation! Thanks for all your work. I can now put this into a .syx or .mid file and automate the process of switching between the various modes. Would you say it's necessary to do a GM or GS reset in between?

So there are four different map choices: SC -55, -88, -88 Pro, -8820.

But, how to switch back to native SCD-70 map? Maybe a value of 0 ? Or is it the same as 8820?

As the SCD-70's midi generator is essentially a SC-8820, you just need to set it to the 8820 map.

I would recommend a GS reset after the map change, as the sysex will not reset other changes made to your module like Chrous /Reverb settings

Wouldn't a GS reset also reset the map setting?

No it wouldn't . This sysex actually forces the device to only use the specified tone map and GS Reset cannot actually clear it. This is what the INST Map change button does on the backend for the SC-8820 and SC-8850. The map will remain active until you power off your device or issue the sysex to revert it back to 8820 mode.

If I had however used the midi Bank Change method (CC0 or CC32) of swapping the instruments, (which changes the default bank of 0 to the bank number specified for example to that of SC-55), a GS reset would be able to clear it.

Bevil, again thanks for clearing up the difference between the two methods.

About this INST MAP button the manual of the SC-D70 talks about... I can't seem to find it on my device. So you think it maybe is a remnant of the SC-8850 or 8820 manual which got copied over?

Yeah that reference was probably copy pasted directly from the 8820 manual. There is no such button on the D70. Pretty sloppy of Roland but oh well.

I see that makes sense then. Thanks again for your great insights.

Just a generic question, Bevil, since you seem to know a lot about the old Roland modules:

Which one would you prefer to play DOS Games such as Descent, Duke Nukem 3D, WarCraft II and the likes (General Midi ones):

SC-55, SC-55 MK2, SC-88, SC-88 Pro, SC-88VL, SC-8820, SC-8840, SC-D70 or rather one of these with a specific instrument map setting and why? :-p

In my opinion I would play the orchestral heavy midi from games circa mid 1990s on the SC-88 or later maps. I feel the SC-55 sound can be a bit 'synthy' . In the mid 1990s, alot of GM compatible midi devices were already on the market and unlike earlier games, developers may not have actually tailor made their soundtracks for the SC-55. For example, Duke3D and Warcraft 2 were actually composed on a SC-88 so this is something you might want to take note of. I personally love Duke3D with the SC-88 pro map. The drum sounds are awesome!

For all Sierra games, use the SC-55 map. Sierra more than any other developer seemed to tailor their sounds for the SC-55. I tried the other sound maps and it seemed to lack the sound balance(some instruments sounded louder than others, or the drum sounds were overwhelming or underwhelming)

An interesting thing to note. For some very early GM game soundtracks written for the SC-55 MKI , the reproduction may not be entirely accurate on later devices including a SC-55 MKII module. That is because the the MK1 had a bug where you could change the instrument bank without sending a program change message as well, and those game soundtracks actually exploited this bug. Later devices corrected this bug and will ignore the commands, thus either playing the wrong instrument or not playing the instrument at all. So for those games, you need a true SC55 first edition. I've forgotten which games these are, but you can probably do a google search.

Thanks. That mostly conforms with my subjective findings concerning Warcraft II and Duke3D. Somehow I liked them on the SC-88 and 88 Pro better than on the SC-55. But the SC-88 somehow sounds a bit 'muffled' compared to the 88 Pro IMHO.

I believe Descent was one of those games that sounds different when comparing the original and MK2 model of the SC-55 which has to do with that bank switch bug you mention. Also I believe in a certain WC2 song, the polyphony of the earlier SC-55 model is maxed out at one point leading to cut off notes. But I'm not sure anymore.

@Bevil: What do you know about the differences between the SC-88 and 88 Pro? I have read somewhere, that the Pro is not entirely true to the original sound when it's in SC-55 map mode. I own both an SC-88 and an 88 Pro and always found that the tonal balance of the instruments sounded a little bit better on the Pro. But what about backwards-compatibility (The Pro's 55 and 88 maps)?

The SC-55 sounds used in the 88 and later modules are in fact the exact samples used in the older module, but they are never going to sound identical due to these reasons. Each of the later modules uses a different DAC and a different REVERB/CHORUS engine. These would give out a somewhat different sound signature .(I would say about 80% to that of an actual SC-55.) The same goes for the 88pro running on 88 mode or the 8820/D70 running on earlier sound maps.

Overall the roland modules up to SC-8820/D70 provide a pretty decent emulation(or subjectively better due to more modern hardware) of earlier modules. This can't be said of the Microsoft GS synthesizer which uses the exact sample sets of the SC-55 but sounds flat and terrible due to a lack of a good reverb engine.

> The SC-55 sounds used in the 88 and later modules are in fact the exact samples used in the older module

Source?

So what about the SC-55 samples in the SC-88 Pro? They're not guaranteed the same?

kolderman wrote on 2020-04-26, 06:47:

> The SC-55 sounds used in the 88 and later modules are in fact the exact samples used in the older module

Source?

This bit is wrong - or rather, not entirely the truth. The Sound Canvas PCM can be found all the way up to inside the Integra 7. However, that does not mean it's exactly the same set of samples.
Instead, the uncompressed source samples used are the same. The compressed versions are different from module to module - the newer the module, the better the quality. However, there are also other differences in the compression algorithms used...
This kind of thing can lead to pretty big differences in sonic quality; see for example the differences between the JV1080/2080 and JD990 waveform sets

For the DAC bit, see my post here (Roland JV-35, but that one is midway between a SC-55 and SC-88, so interesting for this discussion too)

JV35/50 DAC = JV1080 & SC-88VL DAC (UPD63200GS-E2).
Custom Sound Generator chip (=ROM) = SC-55Mk. II (TC6116AF (GP4))
CPU = SC-88 CPU (H8/510)

Note how I didn't write that the SC-88 CPU is the same as the SC-55 CPU. So that's another reason for the differences in sound between the SC-88 and SC-55. See also Re: Apparently not all GS-only sc-55s are the same, some are GM