I bought a Peavey PV8 mixer (off E-bay) to insert between the tone generator cable of our Allen 300 organ and the S100 amp. That way musician's can play guitar & sing when the organ is not playing, through the hifi speakers I put on the organ. (The Allen speakers sounded awful, foam surrounds discintigrated years ago).
The organ uses RCA cable and jacks. The PV8 has two main outputs that are TRS, ie stereo 1/4" phone jacks. I suppose I would blow up a line driver IC if I put a 1/4 mono to RCA jack adapter in there? I have to wire up a custom adapter that leaves the ring out?
I can use the tape recorder outputs of course, which are RCA jacks.
Another question about the Line inputs. Line Inputs 1-4 are TRS. Does a SM58 come now with a TRS plug and twisted pair cable? My cheap dynamic mikes are all 1/8" phone plug with no ring and no shield for the shaft. Of course 5-6 have RCA inputs for those but what are pro bands wiring dynamic mikes?
And the Insert inputs on 1-4 are TRS. What is an insert? How do you use that function?
I've already worked out that the phantom power switch only puts 48 v on the XLR input jacks. So that is for if I want to take my $150 KSM27 condensor mike to church, which is not necessary for guitar because it has no highs.
The organ uses RCA cable and jacks. The PV8 has two main outputs that are TRS, ie stereo 1/4" phone jacks. I suppose I would blow up a line driver IC if I put a 1/4 mono to RCA jack adapter in there? I have to wire up a custom adapter that leaves the ring out?
I can use the tape recorder outputs of course, which are RCA jacks.
Another question about the Line inputs. Line Inputs 1-4 are TRS. Does a SM58 come now with a TRS plug and twisted pair cable? My cheap dynamic mikes are all 1/8" phone plug with no ring and no shield for the shaft. Of course 5-6 have RCA inputs for those but what are pro bands wiring dynamic mikes?
And the Insert inputs on 1-4 are TRS. What is an insert? How do you use that function?
I've already worked out that the phantom power switch only puts 48 v on the XLR input jacks. So that is for if I want to take my $150 KSM27 condensor mike to church, which is not necessary for guitar because it has no highs.
You are thinking about this wrong, the mixer now becomes the core of your audio system and all instrument including the organ are inputs to it.
You don't connect the organ to the mixer output it goes to one of the line inputs. The mixer outputs get connected directly to the amplifier inputs.
Line inputs are TS(unbalanced) not TRS(balanced). Microphones need a mic preamp so they must connect to the XLR input.
This is where you insert outboard processing into the signal chain, like a vocal processor or EQ.
When phantom power is engaged you must ensure no line level sources like guitars or keyboards are connected directly to the XLR inputs. The easiest thing to do is connect them to the line inputs via 1/4 TS cable but if you don't have enough line inputs you can use the XLR input if you insert a DI box between the instrument and mixer.
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Actually, the line in jacks on channels 1-4 are indeed TRS and will handle a balanced input in balanced fashion. It is channels 5-8 that are unbalanced with TS jacks.
The main outputs use a TRS jack, but are not really balanced. You can plug a plain old TS cord into them with no harm, they are made for that. SO a "mono" 1/4" to RCA cord would connect the mixer out to your RCA input amp. I really hate sticking stacked adaptors in input jacks. Just get a cord with 1/4 on one end and RCA on the other.
The RCA input jacks on 5/6 are not for mics, they are for connecting something like a tape deck or a CD player.
An insert jack is basically an FX loop, but all in one jack. It is TRS, and one contact is send and the other return. I never remember which is which, but it is likely printed on it.
Download the owner manual from the PV web site under support.
The main outputs use a TRS jack, but are not really balanced. You can plug a plain old TS cord into them with no harm, they are made for that. SO a "mono" 1/4" to RCA cord would connect the mixer out to your RCA input amp. I really hate sticking stacked adaptors in input jacks. Just get a cord with 1/4 on one end and RCA on the other.
The RCA input jacks on 5/6 are not for mics, they are for connecting something like a tape deck or a CD player.
An insert jack is basically an FX loop, but all in one jack. It is TRS, and one contact is send and the other return. I never remember which is which, but it is likely printed on it.
Download the owner manual from the PV web site under support.
Okay, thanks for the education. 1/4 TS is safe in both inputs and outputs I think I read.
The organ will play songs out of the hymnal, or I will play Carter family or gospel favorites etc on guitar and sing. Never together. So the levels will be set permanently at installation, and the mixer will be behind the back cover of the organ. No fiddling fingers. Guest bands bring their own PA system.
The organ has two S100 amps, each with 3 RCA jack inputs tied together with 0.1 uf capacitors to one op amp input each. Somehow Allen figured out how to keep the tone generator ouputs from blowing each other up coupled together that tightly. I don't want to push my luck with a 4th input, parts for the tone generators are NOT economic. So I'll just lifT an RCA plug from a tone gnerator, run it into the PV8 input 5, take the tape out of the PV8 and run back into the jack on the S100 amp. Cardiod dynamic mike will go to another input, probably 7 or 8 since they are TS. Master volume will remain the swell pedal on the organ, which the organist only changes if the attendance goes up or down.
The Peavey Unity12 mixer I have at home for recording takes dynamic cardioid mikes okay in the 1/4 phone plug slot, just a bit hissy on the cheap mikes I have. I thought the PV8 might have the same gain available on the "line" inputs of channels 1-4. Maybe not. The KSM27 condensor mikes (XLR) I own will not be going to church; they have wide frequency response for piano recordings, and the grand piano at church is certainly loud enough for 60 seats with no mikes or PA. If my voice and guitar weren't so soft (I am not a pro for a reason) I wouldn't use a mike either, but I can't be heard in conversation 10' away.
So thanks for the education. I'll try without an equalizer at first, with the organ speakers on the front right and me singing on the front left with a 20' mike cable there should be no feedback howl problems at all. Oh, the minister preaches into a mike through a cassette player hooked up to a 4" wide triple speaker overhead, which strikes me as totally non-suited for music. Not interfacing with that.
The organ will play songs out of the hymnal, or I will play Carter family or gospel favorites etc on guitar and sing. Never together. So the levels will be set permanently at installation, and the mixer will be behind the back cover of the organ. No fiddling fingers. Guest bands bring their own PA system.
The organ has two S100 amps, each with 3 RCA jack inputs tied together with 0.1 uf capacitors to one op amp input each. Somehow Allen figured out how to keep the tone generator ouputs from blowing each other up coupled together that tightly. I don't want to push my luck with a 4th input, parts for the tone generators are NOT economic. So I'll just lifT an RCA plug from a tone gnerator, run it into the PV8 input 5, take the tape out of the PV8 and run back into the jack on the S100 amp. Cardiod dynamic mike will go to another input, probably 7 or 8 since they are TS. Master volume will remain the swell pedal on the organ, which the organist only changes if the attendance goes up or down.
The Peavey Unity12 mixer I have at home for recording takes dynamic cardioid mikes okay in the 1/4 phone plug slot, just a bit hissy on the cheap mikes I have. I thought the PV8 might have the same gain available on the "line" inputs of channels 1-4. Maybe not. The KSM27 condensor mikes (XLR) I own will not be going to church; they have wide frequency response for piano recordings, and the grand piano at church is certainly loud enough for 60 seats with no mikes or PA. If my voice and guitar weren't so soft (I am not a pro for a reason) I wouldn't use a mike either, but I can't be heard in conversation 10' away.
So thanks for the education. I'll try without an equalizer at first, with the organ speakers on the front right and me singing on the front left with a 20' mike cable there should be no feedback howl problems at all. Oh, the minister preaches into a mike through a cassette player hooked up to a 4" wide triple speaker overhead, which strikes me as totally non-suited for music. Not interfacing with that.
Yes.
Hmmm.. A good idea on one hand but on the other hand you may want some access for tweaking.
This has me puzzled, inputs tied to inputs just doesn't make sense nor does tying all the inputs together.. just seems unnecessary to me but maybe there is something about this setup I'm not understanding correctly. Have you got any pics?
So the tone generators are the organ essentially correct? How many are there? If there are only 2 why aren't they just connected directly to their own S100 amp?
You will have to try it out and see, microphones vary a lot.
Here is a thread that shows some Allen S-100 organ amps. Post 11. Help ID Organ Amp
In the lower rack of amps you can just see the three RCA inputs that are paralleled internally with .1 capacitors. There is only one op amp per S-100 amp, with one input.
An organ has three sections, swell (upper keyboard) great (lower keyboard) and pedal. Each can produce different sounds at the same time. Allen 301 was a digital synthesis organ with waveforms stored as number tables in ROMs. then Rockwell Automation IC's added the numbers together for how ever many tabs (sounds) you had down. I suppose that is the origin of the three inputs to the two amps. They separated the signals into two amps, flute (sine waves) and main (contain edge component) for because of sound source and intermodulation reasons.
As an extra cost option, the organ can have two swell pedals that control volume individually on swell versus great+pedal. This 301 organ just has one.
The inputs play nicely with a pocket radio with earphone volume about 1/3, so I suppose the inputs are the usual 2 vac max variety. Each amp has a master gain pot, which I have turned down to 4 for our small auditorium.
I propose to take one of the RCA inputs, run it out to mixer, mix external sound source (usually silent) into it, and then back. The organ will be silent when I play on external mikes.
The organ as originally installed had front and back 8 ohm speakers connected to each amp, the back mainly parallel but optionally through a fixed attenuator resistor for "antiphonal" effect. There was an antiphonal tab that switched the relay in or out. The S-100 is rated 100 W into 4 ohms. I deleted the back speakers, which were worn out (as were the front), and eliminated the relays and resistors. The relay contacts had oxidized and become unreliable ,going silent when not squeaky clean. I put two KLH23 hifi speakers up front, one for main amp and one for flute amp. These are 10" woofer + 3" tweeter. Low Protestant churches like this one don't usually play music requiring antiphonal trumpets.
Thanks for the interest.
PV8 was a real "bargain". $51 with freight. Hums a bit (power caps probably) left headphone & tape recorder out are silent, master volume slide pot is worn out and loses contact easily. I'll have plenty of time to repair after my rotator cuff surgery next week,I won't be playing any music requiring two arms until June at least.
In the lower rack of amps you can just see the three RCA inputs that are paralleled internally with .1 capacitors. There is only one op amp per S-100 amp, with one input.
An organ has three sections, swell (upper keyboard) great (lower keyboard) and pedal. Each can produce different sounds at the same time. Allen 301 was a digital synthesis organ with waveforms stored as number tables in ROMs. then Rockwell Automation IC's added the numbers together for how ever many tabs (sounds) you had down. I suppose that is the origin of the three inputs to the two amps. They separated the signals into two amps, flute (sine waves) and main (contain edge component) for because of sound source and intermodulation reasons.
As an extra cost option, the organ can have two swell pedals that control volume individually on swell versus great+pedal. This 301 organ just has one.
The inputs play nicely with a pocket radio with earphone volume about 1/3, so I suppose the inputs are the usual 2 vac max variety. Each amp has a master gain pot, which I have turned down to 4 for our small auditorium.
I propose to take one of the RCA inputs, run it out to mixer, mix external sound source (usually silent) into it, and then back. The organ will be silent when I play on external mikes.
The organ as originally installed had front and back 8 ohm speakers connected to each amp, the back mainly parallel but optionally through a fixed attenuator resistor for "antiphonal" effect. There was an antiphonal tab that switched the relay in or out. The S-100 is rated 100 W into 4 ohms. I deleted the back speakers, which were worn out (as were the front), and eliminated the relays and resistors. The relay contacts had oxidized and become unreliable ,going silent when not squeaky clean. I put two KLH23 hifi speakers up front, one for main amp and one for flute amp. These are 10" woofer + 3" tweeter. Low Protestant churches like this one don't usually play music requiring antiphonal trumpets.
Thanks for the interest.
PV8 was a real "bargain". $51 with freight. Hums a bit (power caps probably) left headphone & tape recorder out are silent, master volume slide pot is worn out and loses contact easily. I'll have plenty of time to repair after my rotator cuff surgery next week,I won't be playing any music requiring two arms until June at least.
Thanks Jo.. that was a trip in the way back time machine. What vintage would something like that be?
Hard to believe that even qualifies as a "digital" device by todays standard but it just goes to show how far we have come. Reminds me of when I first started working in telecom manufacturing back in the early 90s.. that particular facility was still producing a primitive solid state telephone switch with a wire wrapped backplane that was only a couple generations removed from the original that employed vacuum tube wafer switches.
Hard to believe that even qualifies as a "digital" device by todays standard but it just goes to show how far we have come. Reminds me of when I first started working in telecom manufacturing back in the early 90s.. that particular facility was still producing a primitive solid state telephone switch with a wire wrapped backplane that was only a couple generations removed from the original that employed vacuum tube wafer switches.
This organ was bought 1980, probably 1978 design or something. Multiple TG's are 12"x20" boards loaded with RCA 4xxx CMOS, plus the 40 pin ROMs and the weird package Rockwell Automation adder IC's. I can relate to the IC's, I was designing a synth for Ford Aerospace in 1979, but we used Shottky TTL to run at >10 mhz for the space shuttle downlink.
Allen schematics are copyrighted and Allen is protective, so nothing is on the net. I've got a S-100 schematic by private message, but it is the early single input version, not this triple input thing. The original S-100 version had the op amp feedback resistor brought out to the swell pedal to make sure nobody bought any amp but Allen.
I suppose as time went on Allen kept adding TG sections to decrease the granularity of the digital approximation. I heard an Allen "computer organ" demo at Foley's in about 1973; I didn't like the sound. That probably did all three sections with one adder, pretty gross granularity. The sound of this one annoyed me at the original church with the bad speakers & 2 vac max out, but with 22 vac out available (new e-caps) and the KLH23 speakers I kind of like it now. The 301 replaced a 1956 Wurlitzer (fall 2017) that was motorboating on wet days, and the e-caps on that were nineties, so general cleaning dust off everything was on the agenda. The Wurlitzer only had 2 sounds anyway, I couldn't get motivated to do all that washing/dusting. Magic! vacuum tubes, however.
The Allen has gold plate key contacts, so if a TG board craters, midi conversion and j-organ synth on a PC laptop is the plan. The S-100 amps will live on longer than I will I imagine. That heat sink is huge, 6"x6"x8", even if it is only one pair of MJ802's out.
I've got an Ampeg mono mixer working that would be perfect for this except being huge. I used to sit on it sideways and play my Ensoniq EPS synth which sat on a piano bench.
Allen schematics are copyrighted and Allen is protective, so nothing is on the net. I've got a S-100 schematic by private message, but it is the early single input version, not this triple input thing. The original S-100 version had the op amp feedback resistor brought out to the swell pedal to make sure nobody bought any amp but Allen.
I suppose as time went on Allen kept adding TG sections to decrease the granularity of the digital approximation. I heard an Allen "computer organ" demo at Foley's in about 1973; I didn't like the sound. That probably did all three sections with one adder, pretty gross granularity. The sound of this one annoyed me at the original church with the bad speakers & 2 vac max out, but with 22 vac out available (new e-caps) and the KLH23 speakers I kind of like it now. The 301 replaced a 1956 Wurlitzer (fall 2017) that was motorboating on wet days, and the e-caps on that were nineties, so general cleaning dust off everything was on the agenda. The Wurlitzer only had 2 sounds anyway, I couldn't get motivated to do all that washing/dusting. Magic! vacuum tubes, however.
The Allen has gold plate key contacts, so if a TG board craters, midi conversion and j-organ synth on a PC laptop is the plan. The S-100 amps will live on longer than I will I imagine. That heat sink is huge, 6"x6"x8", even if it is only one pair of MJ802's out.
I've got an Ampeg mono mixer working that would be perfect for this except being huge. I used to sit on it sideways and play my Ensoniq EPS synth which sat on a piano bench.
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