only a very silent, constant tone from my sid

Testing/Troubleshooting
1

ok, after solving all my psu troubles, i connected the sid module and the core module and powered everything up. uploading the midibox sid software went fine, but i’m getting nothing but a constant, fairly silent tone, of which i can change the pitch by pressing the keys of my keyboard (but the changes are totally out of tune and there is no attack or anything, and as i mentioned it’s pretty quiet…). and the sid (6581R4AR is getting pretty warm) and yes, i did check all voltages they were a-ok, 11,8V for the sid and 5,3V for the core.

edit: and the testtone app just produces some loud clicking/thumping directly after upload (just as after the upload of the sid software).

2

Propably the SID module is not correctly connected, what are the results with the interconnection test?

Best Regards, Thorsten.

3

nothing wrong on the interconnect test (unless it’s a big error if i get 0.01V instead of 0V on CS# for mod wheel value 14)

4

No, 0.01V are fine :wink:

If the interconnection test is working, I cannot say what could cause such an effect. Are you able to test the SID on a C64?

Best Regards, Thorsten.

5

thought so

no, don’t have any c64 to test the sid in… :frowning:

6

Maybe there is somebody in your environment or country who owns a C64 and/or a MIDIbox SID?

Best Regards, Thorsten.

7

i’m in germany (frankfurt a.m. for the next two weeks, after that, cottbus) so i’m pretty sure there’s at least one person with a midibox sid  :stuck_out_tongue: but i cant think of anyone close by who has either.

8

Are you able to receive “snail mails”? Then you could send me the SID for testing together with the return postage

Best Regards, Thorsten.

9

theoretically yes, but since im moving away in less than 14 days its a bad moment, perhaps as soon as i’m in cottbus might be better. i do have other sids i could try in the module but considering that this one was getting pretty warm, im scared they might break…

10

Before you are doing this, one hint. Even you mentioned, that you’ve measured 11.8V (so ca. 12V) between ground and Vdd, do it again when the SID is plugged into the socket.

Because the effect you are describing is exactly the effect when the Vdd voltage is too low (I just remembered this) - it can for example happen, when the 78L12 is soldered in the wrong direction. Please compare it with the pictures on the MBHP_SID page. Don’t try another orientation when you are unsure (it could damage the SID), just compare and measure.

Best Regards, Thorsten.

11

it is mounted as shown in http://www.ucapps.de/mbhp/mbhp_sid_v2.gif , with the heatsink pointing towards the big electrolytic. (and it’s a L78S12CV )

12

…and you’ve measured the voltage again when the SID is in the socket?

I only ask to double check this, because - as mentioned above - when e.g. the voltage for a 6581 is lower than 11V, the SID behaves exactly like you’ve described. With the MBSID and the testtone application…

Best Regards, Thorsten.

13

i’ll check tomorrow morning it’s *still* to hot to do anything right now…

14

finally got around to measuring with the sid inside: 11.7V (11.73V without this time), so no big difference

oh, one more question: is it normal that when the mbsid software is installed that i get all this when booting the synth?

[tt]timestamp 790996000 us: Sysex message: F0 00 00 7E 40 00 01 F7

timestamp 793300000 us: [C0 00] channel 1: program change 0

timestamp 793300000 us: [C0 00] channel 1: program change 0

timestamp 793300000 us: [C0 00] channel 1: program change 0

timestamp 795518000 us: Sysex message: F0 00 00 7E 46 01 0D 00 00 00 F7

timestamp 795527000 us: Sysex message: F0 00 00 7E 46 01 0D 01 00 00 F7

timestamp 795535000 us: Sysex message: F0 00 00 7E 46 01 0D 02 00 00 F7

timestamp 795544000 us: Sysex message: F0 00 00 7E 46 01 02 00 49 6E 74 65 72 6E 61 6C 20 50 61 74 63 68 20 20 7F 00 00 00 00 00 00 00 00 01 40 00 00 00 40 40 40 40 02 00 04 40 00 00 00 00 7F 00 00 00 00 00 40 42 02 00 04 40 00 00 00 00 7F 00 00 00 00 00 40 3E 02 00 04 40 00 00 00 00 7F 00 00 00 00 00 00 00 7F 00 00 7F 00 00 7F 00 20 10 2E 00 00 00 07 10 7F 07 20 00 01 03 7F 01 40 00 01 50 7F 01 60 00 7F 40 40 40 40 00 60 60 20 40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 38 F7

timestamp 795628000 us: Sysex message: F0 00 00 7E 46 02 0D 00 00 00 F7

timestamp 795637000 us: Sysex message: F0 00 00 7E 46 02 0D 01 00 00 F7

timestamp 795645000 us: Sysex message: F0 00 00 7E 46 02 0D 02 00 00 F7

timestamp 795654000 us: Sysex message: F0 00 00 7E 46 02 02 00 49 6E 74 65 72 6E 61 6C 20 50 61 74 63 68 20 20 7F 00 00 00 00 00 00 00 00 01 40 00 00 00 40 40 40 40 02 00 04 40 00 00 00 00 7F 00 00 00 00 00 40 42 02 00 04 40 00 00 00 00 7F 00 00 00 00 00 40 3E 02 00 04 40 00 00 00 00 7F 00 00 00 00 00 00 00 7F 00 00 7F 00 00 7F 00 20 10 2E 00 00 00 07 10 7F 07 20 00 01 03 7F 01 40 00 01 50 7F 01 60 00 7F 40 40 40 40 00 60 60 20 40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 38 F7

timestamp 795738000 us: Sysex message: F0 00 00 7E 46 03 0D 00 00 00 F7

timestamp 795747000 us: Sysex message: F0 00 00 7E 46 03 0D 01 00 00 F7

timestamp 795756000 us: Sysex message: F0 00 00 7E 46 03 0D 02 00 00 F7

timestamp 795765000 us: Sysex message: F0 00 00 7E 46 03 02 00 49 6E 74 65 72 6E 61 6C 20 50 61 74 63 68 20 20 7F 00 00 00 00 00 00 00 00 01 40 00 00 00 40 40 40 40 02 00 04 40 00 00 00 00 7F 00 00 00 00 00 40 42 02 00 04 40 00 00 00 00 7F 00 00 00 00 00 40 3E 02 00 04 40 00 00 00 00 7F 00 00 00 00 00 00 00 7F 00 00 7F 00 00 7F 00 20 10 2E 00 00 00 07 10 7F 07 20 00 01 03 7F 01 40 00 01 50 7F 01 60 00 7F 40 40 40 40 00 60 60 20 40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 38 F7[/tt]

15

well, i just connected the audio out again, and guess what… it now plays the tones i press on the keyboard. this silent sound i heard before is still there and exactly the same as before, but now the sounds that are supposed to be played are played in the foreground. wierd.

16

Strange things happen, but ok…

Yes, the MIDI data which is sent out during startup is ok - these are the patches for the slaves.

The silent sound is the typical background noise of a 6581, the 8580 has a much better s/n ratio…

You can improve it a little by connecting the audio in to ground so long it isn’t used for external audio

Best Regards, Thorsten.

17

ok, i guess i’ll just use a switching jack on the in, so it’s always grounded when not in use.

18

well, i just connected the audio out again, and guess what… it now plays the tones i press on the keyboard. this silent sound i heard before is still there and exactly the same as before, but now the sounds that are supposed to be played are played in the foreground. wierd.

That sounds to me like the typical bug in the SIDs where one can hear the VCA even when no other sounds are being played. Check out this page, in particular the bullet point which begins with “If the interconnection test was successfull…” under “Testing the SID module”. This sound will go away if you change patches and come back as soon as you play another sound.

I believe it can always be heard after a MIDIbox SID is powered up because of the sound played via the SID when a BankStick is found, and things not being reset afterwards. (I plan on removing this ‘BankStick detected’ sound from mine after the hardware is done because I don’t like my synths making noise upon powerup. Just in case I (or someone else) needs to reboot one during a performance, etc.)

-Steve

19

perhaps this is a dumb question, but how do i change patches and/or edit sounds? i have no control surface and no bankstick (yet)

20

perhaps this is a dumb question, but how do i change patches and/or edit sounds? i have no control surface and no bankstick (yet)

Send a MIDI bank change command and read the main MIDIbox SID page.

-Steve