CompuServe Thread

Forum unknown · Audiophile

Sound Effects

19 messages in this thread
#126115From: W. Scott & K. MortonMay 23, 1988 7:10 AM
Barrry: I got Synthia in last week. Was at a SF convention all weekend, so havent had a chance to do any thing except see that it works. I'll play with it as time permits. The first thing I need to do is have it make a Kettle drum sound. The second thing is to rig up an adaptor to feed a stereo sig into my recorder, and a mono sig into my monitor. I'll do that this weekend. -+WMS3+-
#126341From: Barry MassoniMay 24, 1988 1:49 PM
I saw you and Rick discussing ways of feeding to your Recorder in Stereo and your monitor in Stereo. Did you ever come up with a way of doing it with passive electronics?
#126481From: W. Scott & K. MortonMay 25, 1988 7:05 AM
Actually, I want to feed the recorder in stereo and the monitor in MONO. There is no way that I know of to do it RIGHT without the use of active components. A summing circuit made entirely out of resistors would either load down the audio outputs of the Amiga, or drop the level of the signal going to the monitor too much. It would probably reduce the seperation between the two stereo channels as well. If my opamp circuit works (and I'm sure it will) I'll send you a copy of the circuit if you want it. Another alternative would be to make up a circuit using transistors, which would require only a single ended power supply. (Opamps require + and – voltage.) However, I have the opamps, and usually have better luck with them! I've had a few days to fool around with Synthia. I'm not sure it will produce the type of sound effects I want, but it is very sophisticated, and will take me some time to fully explore. The manual could stand some improvement; it is full of typos, and the way the material is presented forces you to flip back and forth through different sections. -+WMS+
#126525From: Barry MassoniMay 25, 1988 10:37 AM
Thanks for the offer to send a circuit diagram but that won't be needed. I have no desire to build one, could design one myself if I did and have a couple of 8x4x2 mixers that I could use if I wanted to. Hmm, on the other hand perhaps there are people our there that could use the diagram. Perhpas it wouldn't hurt to make a diagram in IFF format and put it in the Hardware DL and post a note to all letting them know its there.
#126713From: W. Scott & K. MortonMay 26, 1988 6:30 AM
Yes, if anyone is interested I'll draw the curcuit in DPaint II and (if I EVER get my software from APDC) I'll upload it. -+WMS3+ –
#126713From: W. Scott & K. MortonMay 26, 1988 6:30 AM
Yes, if anyone is interested I'll draw the curcuit in DPaint II and (if I EVER get my software from APDC) I'll upload it. -+WMS3+ –
#126525From: Barry MassoniMay 25, 1988 10:37 AM
Thanks for the offer to send a circuit diagram but that won't be needed. I have no desire to build one, could design one myself if I did and have a couple of 8x4x2 mixers that I could use if I wanted to. Hmm, on the other hand perhaps there are people our there that could use the diagram. Perhpas it wouldn't hurt to make a diagram in IFF format and put it in the Hardware DL and post a note to all letting them know its there.
#126635From: Richard Rae/SYSOPMay 25, 1988 8:40 PM
FYI, opamps don't "require + and – voltage". This is a question of perspective. The only restriction is that your zero signal level must be set such that both the positive and negative peaks of the signal you will be working with fall within the supply rails. For example, if you're running from ground and a +15 volt supply, you use two resistors and a capacitor to establish a 7.5 volt reference and use that to bias the opamps. Trivial, really. The other issue is how much voltage you actually need. Again, no problem: the LM324, for example, can handle the Amiga's bandwidth with no difficulty, and it will run quite admirably off a single 5 volt logic supply.
#126714From: W. Scott & K. MortonMay 26, 1988 6:32 AM
Quite so. I recall designing op amp circuits to run off single ended supplies in school (about 13 years ago!) Like I said, my analog design skills are rusty! -+WMS3+
#126714From: W. Scott & K. MortonMay 26, 1988 6:32 AM
Quite so. I recall designing op amp circuits to run off single ended supplies in school (about 13 years ago!) Like I said, my analog design skills are rusty! -+WMS3+
#126635From: Richard Rae/SYSOPMay 25, 1988 8:40 PM
FYI, opamps don't "require + and – voltage". This is a question of perspective. The only restriction is that your zero signal level must be set such that both the positive and negative peaks of the signal you will be working with fall within the supply rails. For example, if you're running from ground and a +15 volt supply, you use two resistors and a capacitor to establish a 7.5 volt reference and use that to bias the opamps. Trivial, really. The other issue is how much voltage you actually need. Again, no problem: the LM324, for example, can handle the Amiga's bandwidth with no difficulty, and it will run quite admirably off a single 5 volt logic supply.
#126481From: W. Scott & K. MortonMay 25, 1988 7:05 AM
Actually, I want to feed the recorder in stereo and the monitor in MONO. There is no way that I know of to do it RIGHT without the use of active components. A summing circuit made entirely out of resistors would either load down the audio outputs of the Amiga, or drop the level of the signal going to the monitor too much. It would probably reduce the seperation between the two stereo channels as well. If my opamp circuit works (and I'm sure it will) I'll send you a copy of the circuit if you want it. Another alternative would be to make up a circuit using transistors, which would require only a single ended power supply. (Opamps require + and – voltage.) However, I have the opamps, and usually have better luck with them! I've had a few days to fool around with Synthia. I'm not sure it will produce the type of sound effects I want, but it is very sophisticated, and will take me some time to fully explore. The manual could stand some improvement; it is full of typos, and the way the material is presented forces you to flip back and forth through different sections. -+WMS+
#126634From: Richard Rae/SYSOPMay 25, 1988 8:39 PM
I assume you meant "recorder in stereo and monitor in MONO…". It's trivial on a 1000, and in fact I addressed this in a column quite some time ago. Apparently it'll be a bit trickier on a 2000 (I will pass on any comments I might make about the 1000 continuing to be superior to the new machines in bizarre and wonderful ways 8). If you're driving a high enough impedence, yes, you should be able to do it with a resistive mixer without too much loss of stereo imaging (actually the Amiga's output is too wide for my tastes anyway). If you're willing to solder about inside your 2000, it can be done with zero loss of imaging. Yell if you want more data. Rick
#126662From: Barry MassoniMay 25, 1988 9:46 PM
The 1000 is superior to the new machines? No wonder they're being replaced! I don't really need to "record in stereo and monitor in MONO…" Why anyone would want to do that beyond me! Hey, why not record in stereo while watching TV, or taking a shower! {8)
#126721From: Richard Rae/SYSOPMay 26, 1988 9:37 AM
I can answer that one. Lots of times I'm not really using the audio capabilities of Ami, like when I'm just listening to ^G beeps from Access! or incidental sound effects from some game. For those times, I want to just power on the computer and use it, and for that the tinny speaker in my 1080 works just fine. When I'm doing music work or demonstrating the system, I want stereo and lots of it. For those times, I flip on my stereo system and kick over to the Amiga input. Now the reason for cabling so you can "record in stereo and monitor in mono", IMHO, is that the ONLY thing you have to do to switch modes is turn the stereo on and off. No cable swapping, no crawling around behind the computer or stereo, no loss of functionality. That's worth wiring a special cable, at least as far as I'm concerned.
#126721From: Richard Rae/SYSOPMay 26, 1988 9:37 AM
I can answer that one. Lots of times I'm not really using the audio capabilities of Ami, like when I'm just listening to ^G beeps from Access! or incidental sound effects from some game. For those times, I want to just power on the computer and use it, and for that the tinny speaker in my 1080 works just fine. When I'm doing music work or demonstrating the system, I want stereo and lots of it. For those times, I flip on my stereo system and kick over to the Amiga input. Now the reason for cabling so you can "record in stereo and monitor in mono", IMHO, is that the ONLY thing you have to do to switch modes is turn the stereo on and off. No cable swapping, no crawling around behind the computer or stereo, no loss of functionality. That's worth wiring a special cable, at least as far as I'm concerned.
#126662From: Barry MassoniMay 25, 1988 9:46 PM
The 1000 is superior to the new machines? No wonder they're being replaced! I don't really need to "record in stereo and monitor in MONO…" Why anyone would want to do that beyond me! Hey, why not record in stereo while watching TV, or taking a shower! {8)
#126634From: Richard Rae/SYSOPMay 25, 1988 8:39 PM
I assume you meant "recorder in stereo and monitor in MONO…". It's trivial on a 1000, and in fact I addressed this in a column quite some time ago. Apparently it'll be a bit trickier on a 2000 (I will pass on any comments I might make about the 1000 continuing to be superior to the new machines in bizarre and wonderful ways 8). If you're driving a high enough impedence, yes, you should be able to do it with a resistive mixer without too much loss of stereo imaging (actually the Amiga's output is too wide for my tastes anyway). If you're willing to solder about inside your 2000, it can be done with zero loss of imaging. Yell if you want more data. Rick
#126341From: Barry MassoniMay 24, 1988 1:49 PM
I saw you and Rick discussing ways of feeding to your Recorder in Stereo and your monitor in Stereo. Did you ever come up with a way of doing it with passive electronics?