There are a few possibilities, but there must a best one. We would want to keep the stock reverb as is.
The schematic is at: http://www.keyboardpartner.de/hammond/diagrams/H-100/h-100_full.jpg
Simple as possible is best. Line level 1.1v is probably the way to go, though guitar instrument level may be preferred by some.
Any sound ideas welcomed (no pun).
The schematic is at: http://www.keyboardpartner.de/hammond/diagrams/H-100/h-100_full.jpg
Simple as possible is best. Line level 1.1v is probably the way to go, though guitar instrument level may be preferred by some.
Any sound ideas welcomed (no pun).
I'll take a shot. The Channel B wire under the Reverb area looks good. The level is indicated at 60mV with the second harmonic of key 25 pressed at maximum volume--drawbar maxed. I'm guessing the level is somewhere between Instrument and Line. Have no way to tell since my machine is in the OR. The FX would only function on this one channel, but the Reverb only works on the other, as well. So there's always 50-50 clean/FX blend. Half the effect would also wind up in the bass channel. A shielded wire could run to a jack box on the back of the cabinet.
The gate of V305 (7199) is another possibility. With a stereo FX unit, both channels may be modified or just one. This level is indicated as also 60mV, but with pedal 13 mellow (fundamental I think) max. volume and drawbar maxed. There is space on the left side of the amp for a jack.
If someone could measure the levels while playing a chord in the middle of a keyboard with the Bombard preset key on, and maybe one of the lower bass notes, that would be helpful. This will determine what we can get away with.
The gate of V305 (7199) is another possibility. With a stereo FX unit, both channels may be modified or just one. This level is indicated as also 60mV, but with pedal 13 mellow (fundamental I think) max. volume and drawbar maxed. There is space on the left side of the amp for a jack.
If someone could measure the levels while playing a chord in the middle of a keyboard with the Bombard preset key on, and maybe one of the lower bass notes, that would be helpful. This will determine what we can get away with.
I'm not taking the tab box apart to get to the back of the reverb switch.
With Bombard, 5 black notes down with laundry detergent tub, two pedal notes down with brick, both brown pedal drawbars out, I'm getting 0.5 VAC at pin 4 of P301. Ear plugs in, this is loud!
Which grid of V305 you want, the triode or the pentode? This is after the bass removal filter. Of course, reverb typically has the bass left out. But for general room effects like cathedral or tile bathroom reverb, you might want the bass included. My digitec quad had both.
With Bombard, 5 black notes down with laundry detergent tub, two pedal notes down with brick, both brown pedal drawbars out, I'm getting 0.5 VAC at pin 4 of P301. Ear plugs in, this is loud!
Which grid of V305 you want, the triode or the pentode? This is after the bass removal filter. Of course, reverb typically has the bass left out. But for general room effects like cathedral or tile bathroom reverb, you might want the bass included. My digitec quad had both.
Thank you for taking the time. The calibration level on the signal B wire is close to where you measured, so no need to open.
Looks like pin 7, pentode grid 1, R353 and R380, .01v in the circle. Perhaps there is no need to measure anything else. It appears the calibration voltages are 1/10th actual playing levels.
Either location may use 9v stompboxes without clipping! A mounting plate could be attached across the cabinet just above the pedals with Velcro attachment of the boxes just like the guitar rigs. The pedals then can "easily" be swithed on/off with the feet like the theatre organ pistons. I would use channel B because it is the non-vibrato, although some bizarre sounds could be achieved there with FX additions. It might drive the FX crazy though, and everyone else, too.
Yes, I see now if FX is placed at V305 and/or V308 the bass is not affected. Interesting, I recall the Leslie 610 that goes with this organ does not have a spinning bass, but that has nothing to do with FX or reverb. Switched jacks could be used so it's just a matter of disconnecting the cables to return to stock.
A separate loop could be made for the bass.
As for the jacks, I contemplated a large size, blank stomp box enclosure mounted wherever, I guess through the speaker panel or on the back if one does not want to butcher the cab.
Most Pro FX units are designed for line level. I don't know if they would work good, at this level. What do you think?
Ok, I'm now thinking fuzz, echo, flanger, "Leslie" emulators, etc...
Looks like pin 7, pentode grid 1, R353 and R380, .01v in the circle. Perhaps there is no need to measure anything else. It appears the calibration voltages are 1/10th actual playing levels.
Either location may use 9v stompboxes without clipping! A mounting plate could be attached across the cabinet just above the pedals with Velcro attachment of the boxes just like the guitar rigs. The pedals then can "easily" be swithed on/off with the feet like the theatre organ pistons. I would use channel B because it is the non-vibrato, although some bizarre sounds could be achieved there with FX additions. It might drive the FX crazy though, and everyone else, too.
Yes, I see now if FX is placed at V305 and/or V308 the bass is not affected. Interesting, I recall the Leslie 610 that goes with this organ does not have a spinning bass, but that has nothing to do with FX or reverb. Switched jacks could be used so it's just a matter of disconnecting the cables to return to stock.
A separate loop could be made for the bass.
As for the jacks, I contemplated a large size, blank stomp box enclosure mounted wherever, I guess through the speaker panel or on the back if one does not want to butcher the cab.
Most Pro FX units are designed for line level. I don't know if they would work good, at this level. What do you think?
Ok, I'm now thinking fuzz, echo, flanger, "Leslie" emulators, etc...
The digitec Quad 4 had all of those in stereo, 400 programs in all. 2 VAC in and out. I really hope I've just misplaced it. Audacity program has all those programs too. but you'd have to buy an industrial PC to run it that boots up to a known program without input. Then figure some way to switch programs. The Quad 4 had a up down pushbutton and a 2 digit LED display showing program #. Peavey made one too, although I've never seen on on craigslist.
Now that I see the built in reverb is mono, I think maybe in future I'd put SS relays down in the amp chassis and control the on-off of reverb with the tab swith switching a Dc voltage. I've been collecting parts to replace the amp chassis with 3 SS channels and lighten up the power draw, but what I've got works so well why mess around. maybe on the unrestored unit.
Now that I see the built in reverb is mono, I think maybe in future I'd put SS relays down in the amp chassis and control the on-off of reverb with the tab swith switching a Dc voltage. I've been collecting parts to replace the amp chassis with 3 SS channels and lighten up the power draw, but what I've got works so well why mess around. maybe on the unrestored unit.
You like the Digitec Quad 4. The controls appear suitable for organ. The buttons have to be big and separated by sufficient space and they are. For the price, it's seems like a good choice to experiment. Better units have less distortion and perhaps better sound, but there is distortion in the tone wheels and of course in all those tubes anyway.
Just looking through the User Manual, I see that it is very flexible. Also a 3-button optional footswitch that can change programs, or a simple n.o. switch to bypass may be used.
This approach seems better than the PC idea.
I thought of replacing the amp with SS, too. For now I figure if it isn't broke, don't fix it. The power draw is minimal. The boat-anchor transformer is that big mostly because of the 6.3v heater supply for all those tubes, plus overrated for reliability. What I do not like about the power supply is the leakage. May articles and opinions on what to do about grounding, or if it should be done at all. I measure full line voltage from one of the phases to my system ground, and a little less on the other. I received a shock when hooking up my PC to look at waveforms. The current is very low, but still not safe for some people.
Grounding the chassis will degrade the transformer and connecting wire insulation faster than normal. I read someone used a resistive ground I suppose to alleviate that. The wattage rating should be high in case of a short, so the circuit breaker on the line can trip. People get shocked by touching microphones and the metal of the control panel and the faceplates.
Thanks again.
Just looking through the User Manual, I see that it is very flexible. Also a 3-button optional footswitch that can change programs, or a simple n.o. switch to bypass may be used.
This approach seems better than the PC idea.
I thought of replacing the amp with SS, too. For now I figure if it isn't broke, don't fix it. The power draw is minimal. The boat-anchor transformer is that big mostly because of the 6.3v heater supply for all those tubes, plus overrated for reliability. What I do not like about the power supply is the leakage. May articles and opinions on what to do about grounding, or if it should be done at all. I measure full line voltage from one of the phases to my system ground, and a little less on the other. I received a shock when hooking up my PC to look at waveforms. The current is very low, but still not safe for some people.
Grounding the chassis will degrade the transformer and connecting wire insulation faster than normal. I read someone used a resistive ground I suppose to alleviate that. The wattage rating should be high in case of a short, so the circuit breaker on the line can trip. People get shocked by touching microphones and the metal of the control panel and the faceplates.
Thanks again.
The Digitec Quad 4 is obsolete. Only a few beat up units (for big $) on eBay. Sweetwater suggests the following replacements. https://www.sweetwater.com/store/detail/StudioQuad4
The Lexicon MX400 is 4 in 4 out ~$300. Manual: http://rdn.harmanpro.com/product_do.../MX400-MX400XL_Manual_18-0446V-D_original.pdf
I looked for the footswitch for this one and the mfr. has discontinued it. All these units seem to have a short lifecycle. The buttons were too close anyway. It was a two-switch TRS, probably two n.o. switches inside. I would want the mute function at least.
If anyone has a better idea for a unit, please post.
Thanks.
The Lexicon MX400 is 4 in 4 out ~$300. Manual: http://rdn.harmanpro.com/product_do.../MX400-MX400XL_Manual_18-0446V-D_original.pdf
I looked for the footswitch for this one and the mfr. has discontinued it. All these units seem to have a short lifecycle. The buttons were too close anyway. It was a two-switch TRS, probably two n.o. switches inside. I would want the mute function at least.
If anyone has a better idea for a unit, please post.
Thanks.
Ha! Found the Digitech Studio V2 Quad and the power supply.
It was under a box of relays I bought to make a stop (preset) sequencer for the H182.
But it takes stereo phone 1/4 plugs, and all my RCA jack-1/4 phone adapters are mono. So I'm afraid of shorting out the op amp line drivers if I plug those in the outputs. Project delayed until I make a parts order.
Probably has bad PS e-caps anyway, everything else I bought from that band in 2010 did. Except the SP2-XT speakers. Lots of cheap damage due to 1/4 phone plugs in the wrong hole, too. Incinerated input resistors in the PA amp.
I do have a compatible foot switch.
I saw a miniature version of one of these on local craigslist in the fall for $65. Probably had a later microprocessor. So keep looking around. This one is Made in USA!
Peavey genuine rack multi-effect would also be a score.
Edit, found a stereo phone plug I bought about 1976 and a RCA jack bought in the 80's. Trial on the hifi between mixer & power amp in a few hours.
It was under a box of relays I bought to make a stop (preset) sequencer for the H182.
But it takes stereo phone 1/4 plugs, and all my RCA jack-1/4 phone adapters are mono. So I'm afraid of shorting out the op amp line drivers if I plug those in the outputs. Project delayed until I make a parts order.
Probably has bad PS e-caps anyway, everything else I bought from that band in 2010 did. Except the SP2-XT speakers. Lots of cheap damage due to 1/4 phone plugs in the wrong hole, too. Incinerated input resistors in the PA amp.
I do have a compatible foot switch.
I saw a miniature version of one of these on local craigslist in the fall for $65. Probably had a later microprocessor. So keep looking around. This one is Made in USA!
Peavey genuine rack multi-effect would also be a score.
Edit, found a stereo phone plug I bought about 1976 and a RCA jack bought in the 80's. Trial on the hifi between mixer & power amp in a few hours.
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Okay, the Peavey dual-deltafex competes with the above and seems to list for $239
https://peavey.com/products/index.cfm/item/668/115819
You may be able to see one at a local dealer.
Had problems with the soldering iron not heating to make effects cable then had to take care of business today.
Dual-Deltafex panel controls are not intuitive. No buttons, and the unit is single channel stereo or dual channel mono. Looks like only one effect runs at a time, no fast switching between effects like Quad 4 or probably all the other ones. However, it does have rotary and the speed could be controlled by footswitch. It may also be muted there, too. It does have input AND output level controls; this is good for Hammonds.
I saw one Quad 4 with a broken switch. Perhaps those could be wired to user-preferred locations. Shielded guitar wire.....
Another idea. It would be nice to utilize some of the tabs that are not used. For instance, I would never use vibrato, and probably not celeste. They are both artificial. An effect device could go in the circuits the player would never use. A little more difficult, though.
Also, we are not confined to just one reverb unit. Belton makes a long delay suitable for organ. It is closer to echo. It has three springs, two long, and one short (if I recall). Not expensive. H-100 has three adjustment levels so if it's too much, it can be reduced.
Incidentally, the resistor wire I bypassed was supposed to be 68R not 56R. #@$&%!!!!
I saw one Quad 4 with a broken switch. Perhaps those could be wired to user-preferred locations. Shielded guitar wire.....
Another idea. It would be nice to utilize some of the tabs that are not used. For instance, I would never use vibrato, and probably not celeste. They are both artificial. An effect device could go in the circuits the player would never use. A little more difficult, though.
Also, we are not confined to just one reverb unit. Belton makes a long delay suitable for organ. It is closer to echo. It has three springs, two long, and one short (if I recall). Not expensive. H-100 has three adjustment levels so if it's too much, it can be reduced.
Incidentally, the resistor wire I bypassed was supposed to be 68R not 56R. #@$&%!!!!
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