I would like to synchronize several amps I have used in an outdoor system at my home. What I don't know is what issues I will encounter or the results I should expect. I have 3 6 channel Class D amps that are less than 75 feet from a central area I would like to be able to control the signal. All of these outdoor amps have 6 analogue RCA connectors. I have previously installed (many years ago) direct buried data cable that contains 6 awg 24 twisted pair and 4 awg 22 that are shielded with foil and a braided ground. A total of 12 24 gauge conductors and 4 22 gauge with a braided ground that I am unsure of the total gauge.
I want to be able to tap the signal from my Dennon AVR3200 or Technics SA-AX720 to feed these satellite amps. OR just use a mixer to send 3 left and 3 right if DAC is going to lose the extra channels when its not encoded for more than 2 channels. I'll also be looking to seperatly get signal to 4 self powered Sub woofers in strategic locations that are not as distant.
I would like to be able to plug in a guitar and a Microphone at the central location or by RF or Bluetooth wireless.
Can I send a digital signal over this distance and extract it at multiple points? would analogue pre-amp out be strong enough or should I expect to need a speaker level signal.
I am not seeking to have perfect reproduction or bragging rights on how much I spend on equipment, This is simply so we can sing along and play amplified instruments whether in the man cave, at the fire pit or in the den. and I am using equipment I have accumulated over many years and willing and capable of using a soldering iron and components as needed.
Why has no one developed a bluetooth router or opensource wi-fi that can do this?
I want to be able to tap the signal from my Dennon AVR3200 or Technics SA-AX720 to feed these satellite amps. OR just use a mixer to send 3 left and 3 right if DAC is going to lose the extra channels when its not encoded for more than 2 channels. I'll also be looking to seperatly get signal to 4 self powered Sub woofers in strategic locations that are not as distant.
I would like to be able to plug in a guitar and a Microphone at the central location or by RF or Bluetooth wireless.
Can I send a digital signal over this distance and extract it at multiple points? would analogue pre-amp out be strong enough or should I expect to need a speaker level signal.
I am not seeking to have perfect reproduction or bragging rights on how much I spend on equipment, This is simply so we can sing along and play amplified instruments whether in the man cave, at the fire pit or in the den. and I am using equipment I have accumulated over many years and willing and capable of using a soldering iron and components as needed.
Why has no one developed a bluetooth router or opensource wi-fi that can do this?
This has been done before. Look at Peavey loudspeaker management systems. VSX26e, VSX48e Page 111 of the catalog. There are other PA equipment vendors. There are much cheaper long distance line level interfaces over Cat 5 wire, or radio link, or toslink. These are single channel or stereo only. Newark.com (farnell US) sells them, but the parts-express.com catalog is more user friendly. The newark database, you have to know the exact name of what you are looking for. Parts-express is US Ohio based, farnell operates worldwide. A "mixer" generally has at least 4 outputs, a master send, a monitor send, a effects/tape send, and a headphone send. If you can limit your outputs to four stereo channels, one of those is much cheaper. Some of them have differential outputs for hundreds of feet of hum free transmission, most of them are single ended only. The three Peavey mixers I own are single wire drive only, good maybe for 100' with twisted pair to the amps on the stage.
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Exactly the road signs I was seeking. indianajo
Thank you I have never tried sending a low level signal over a distance or with twisted pairs so I had no idea it was even a real thing. I added all that buried cable when I put in my Irrigation drainage and lighting, I had lots of materials I wasn't willing to toss and figured Id find a way to use them for audio video or something with a cool factor eventually. That was 15 years ago LOL. And boy am I glad I put all that copper in the ground, including 100s of feet of 10 gauge for speakers. the cost would be crazy today.
With that direction I can move forward to soldering up some terminal blocks and figure out how much resistance I have on the lines and how much signal voltage will be needed. Ill give it a go with my old amps and mixers first.
I can't justify buying the Peavey loudspeaker management system new at this time but I know what to look for at the pawn shops.
Thank you I have never tried sending a low level signal over a distance or with twisted pairs so I had no idea it was even a real thing. I added all that buried cable when I put in my Irrigation drainage and lighting, I had lots of materials I wasn't willing to toss and figured Id find a way to use them for audio video or something with a cool factor eventually. That was 15 years ago LOL. And boy am I glad I put all that copper in the ground, including 100s of feet of 10 gauge for speakers. the cost would be crazy today.With that direction I can move forward to soldering up some terminal blocks and figure out how much resistance I have on the lines and how much signal voltage will be needed. Ill give it a go with my old amps and mixers first.
I can't justify buying the Peavey loudspeaker management system new at this time but I know what to look for at the pawn shops.
If you're hitting pawn shops & ebay, look at the Allen & Heath mixers. I think they have real differential drive outputs. These are usually on TRS sockets, ie 1/4" stereo phone plugs with the main drive on the tip, invert channel on the ring and the shield on the shaft.
Then some new power supply capacitors, some new pots in the high use areas, you might have something you can use to drive 100' twisted pair.
The differential drive concept goes back to Bell telephone; was used in Hammond organ "tone cabinets" of the late 40's & 50's to have amplification up to 100' away from the organ console without hum.
I'm trying to reuse a PV8 mixer to insert a mike into an Allen organ amp, but the ****ed thing is surface mount parts. I found the bad solder joint but don't know how to correct it. 80's & early 90's mixers have DIP IC's you can actually work on with a $60 soldering iron.
Then some new power supply capacitors, some new pots in the high use areas, you might have something you can use to drive 100' twisted pair.
The differential drive concept goes back to Bell telephone; was used in Hammond organ "tone cabinets" of the late 40's & 50's to have amplification up to 100' away from the organ console without hum.
I'm trying to reuse a PV8 mixer to insert a mike into an Allen organ amp, but the ****ed thing is surface mount parts. I found the bad solder joint but don't know how to correct it. 80's & early 90's mixers have DIP IC's you can actually work on with a $60 soldering iron.
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I have re-seated surface mount chips with a $20 soldering iron, It took some bizarre faces and a strained sphincter but I was successful at getting the Sony GPS dongle to work again. While I was winging it When I watch Louis Rossmann he does more or less the same thing with better tools and a microscope, YouTube I think a harbor freight plastic welder could work like the hot air gun he uses.
If you can listen to Dave at EEVblog that long he has a tutorial on surface mount. the whole series is worth watching. YouTube
just practice on something throw away its not that hard just intimidating, most components can take a lot more short time heat than we image (700f for 20 seconds). I used a silver bearing flux for lower heat but eventually it overheated and de soldered again.
Thanks again for the suggestions its been a while since I was a professional in electronic repair (Curtis Mathis Magnavox warrenty) I have to re-educate myself often.
If you can listen to Dave at EEVblog that long he has a tutorial on surface mount. the whole series is worth watching. YouTube
just practice on something throw away its not that hard just intimidating, most components can take a lot more short time heat than we image (700f for 20 seconds). I used a silver bearing flux for lower heat but eventually it overheated and de soldered again.
Thanks again for the suggestions its been a while since I was a professional in electronic repair (Curtis Mathis Magnavox warrenty) I have to re-educate myself often
.You can run unbalanced signal (even over twisted pair or just speaker wire) hundreds of feet without hum pickup if the impedance is low. By low I mean in the 50 to 100 ohm range. Just hang a 47 to 100 ohm resistor at the receiving end. A small “chip amp” like an LM1875 can drive multiple parallel runs, until the total load hits about 4 ohms.
If you want better fidelity and noise immunity, use double terminated 75 ohm coax. Terminate the load in 75 ohms, use 75 ohms in series at the driver amplifier output. You can hang as many of those 150 ohm loads off the driver chip as it will handle. They make op amps specifically for this (ie. AD815), but a gainclone chip works just fine. An E-bay kit and a wall wart is as good as anything if you don’t want to design it. An LM386, although tempting, isn’t quite up to the task unless it’s just voice where you don’t even care about quality. An LM380 would be ok, but one of the usual gainclone chips is better and can drive heavier loads without distorting.
If you want better fidelity and noise immunity, use double terminated 75 ohm coax. Terminate the load in 75 ohms, use 75 ohms in series at the driver amplifier output. You can hang as many of those 150 ohm loads off the driver chip as it will handle. They make op amps specifically for this (ie. AD815), but a gainclone chip works just fine. An E-bay kit and a wall wart is as good as anything if you don’t want to design it. An LM386, although tempting, isn’t quite up to the task unless it’s just voice where you don’t even care about quality. An LM380 would be ok, but one of the usual gainclone chips is better and can drive heavier loads without distorting.
Thanks I watched the video. Apparently surface mount boards have a chemical coating that prevents solder from bridging pins. News to me! I have had a huge problem with solder bridging pins even on 0.1" spaced dip packages TO-18 TO-92 & even TO-220 on paper boards & G14 FRP. Have to go in & scrape out in between with a pick, which could overheat the die obviously.
If you're an experienced diy, you can take your analog signal, run it through one op amp, then out to dozens of op amps each driving it's own twisted pair. Just keep the runs short on the main "mixer" op amp, and keep it inside a metal housing with RF barriers at all entry points. Use inverting for main wire and non-inverting for pair wire for best hum rejection. This differential signal requires power amps with 3 pin input jacks and op amp common mode rejection feature. You can use the 1 wire for the signal (op amp output) and the twisted pair for analog ground out and in in the cheap line driver setup used by cheap mixers like my Peavery PV8 and Unity 12.
WG SKI's 50 ohm & 75 ohm scheme with chip amp driver and load resistor at the amp end works, but you have to keep the signal down below 2 vac to avoid overwhelming your amps out in the field. LM3886 and other chip amps are capable of 20 VAC signals if the power supply is high enough.
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A 50 ohm system will work as well (or better) than 75, but the cable is going to be more expensive than video cable. With eiither system you get a natural 6dB attenuation from double terminating (it is a voltage divider), so less likely to overdrive consumer levels equipment inputs. If you’re still concerned, use a pi attenuator (closed loop gain minus 6 dB) on the receiver. In any case, no need to run the power supply up over 18 or 24 volts, and a single supply application circuit can be used.
Ah so that's were the majic is.
I'm glad my listening to Louis rant about macs and life has been able to help. I really have great respect for Dave and have learned a lot from him, but I wish I could filter that squeak from his voice as it grates on me badly.
Do have you got any suggestions for terminal strips. I will have a total of at least 64 conductors meeting and I was going to put them in a box on the wall outside my man cave perch. Would a Telephone exchange type work or should I look for some other type ? I'm thinking that new scope needs to be for my Birthday , I don't wanna wait till Christmas.
After going a few years without a decent system hooked up,(self flagellation for doing dumb stuff that broke things) I find that having quality music makes me happier and more productive all day.
I didn't realize that was why either. I know it can bridge when you use too much solder and are sloppy, but I didn't know the surface tension of the solder wasn't the reason the balls coalesce. I just knew if you fiddle with it everything goes were it is supposed to like magic. .
I'm glad my listening to Louis rant about macs and life has been able to help. I really have great respect for Dave and have learned a lot from him, but I wish I could filter that squeak from his voice as it grates on me badly.
I already have cable buried, I think it is network cable, it does have 4 shielded conductors but I have not been able to find any specs like the impedance or capacitance. I had an Idea that it would work but was not sure of voltage levels or many of the caveats that you have made me aware of. this should be pretty fun. I'll be experimenting with the cheap Class D amps before I connect to any of my good stuff, I already learned my lesson with the tanberg TR-2055 that lost a channel and needs to go on the bench when I get schematics.
Do have you got any suggestions for terminal strips. I will have a total of at least 64 conductors meeting and I was going to put them in a box on the wall outside my man cave perch. Would a Telephone exchange type work or should I look for some other type ? I'm thinking that new scope needs to be for my Birthday , I don't wanna wait till Christmas.
After going a few years without a decent system hooked up,(self flagellation for doing dumb stuff that broke things) I find that having quality music makes me happier and more productive all day.
These closed style "euro" barrier strips have screws to hold the wires down and their own insulation. https://www.newark.com/wieland-electric/21-311-0853-0/terminal-block-eurostyle-8-position/dp/01M9997 The ones that don't go up to 12 ga like this one are easier to get 26 ga etc under the screws without the wire slipping out. This one goes to 16 ga. There were cheaper ones under mcmelectronics.com but newark closed that warehouse and I can't find them today, although everything moved to n.carolina.
Telephone type punchdown blocks oxidize and block signals on low energy type circuits like line level, 2 vac 0.1 ma. We banned them for our factory data hookups, whereas the screw terminals with crimp on terminals maintained connectivity over a decade. The blocks requiring crimp terminals on the wires are obsolete now IMHO now that closed entry terminal strips are available. Telephone signals were 48 v which is not a "dry circuit", so the punchdown blocks were not a problem on telephones.
I was paying $1.50 for a 12 entry euro terminal block. Make sure it has screwholes for mounting between wire terminals. The ones I bought require 1" long 4-40 screws or 3 mm x 25 mm. Use elastic stop nuts so they don't come unmounted. I get this hardware from mcmaster.com, in packs of 50 or 100. Get the passthrough drill for the mount screws on the same $8 freight, unless you have a #1-60 drill set already.
Scopes are limited to 80 v signals, or cost $600 up. I make do without one. I have a Simpson 266xlpm meter which goes down to 2.5 vac. I can see 50 mv on it. It has no electrolytic caps in it to expire and works still after 33 years. Of course dvm are handier for dc since the polarity doesnt matter, but they miss short pulses like loose solder connection pops and produce random numbers on music signals. The fluke RMS DVmeter stops at 7000 hz so ultrasonic oscillation is invisible. Caught some in an op amp circuit with the Simpson 266. Use a .047 uf capacitor (400 v) series negative probe to block DC from showing up on AC scale. If a signal exists, you can't hear it, and it still passes through a 390 pf blocking capacitor, it is an ultrasonic.
I've quit working since 2008, when I had only a FM radio with a 2" speaker working. I now have stereo 70w/ch in my music room with 2000 LP's and SP2-XT speakers, stereo 125 w/ch with the HDTV with 6" coaxial speakers in newark boxes, and mono 30 w/ch with 2 way 15"+horn wedge monitor in my summer trailer. All amps repaired/improved by me from the glory days of US production. Plus 2 hammond H100 organs working and 2 working pianos.
Telephone type punchdown blocks oxidize and block signals on low energy type circuits like line level, 2 vac 0.1 ma. We banned them for our factory data hookups, whereas the screw terminals with crimp on terminals maintained connectivity over a decade. The blocks requiring crimp terminals on the wires are obsolete now IMHO now that closed entry terminal strips are available. Telephone signals were 48 v which is not a "dry circuit", so the punchdown blocks were not a problem on telephones.
I was paying $1.50 for a 12 entry euro terminal block. Make sure it has screwholes for mounting between wire terminals. The ones I bought require 1" long 4-40 screws or 3 mm x 25 mm. Use elastic stop nuts so they don't come unmounted. I get this hardware from mcmaster.com, in packs of 50 or 100. Get the passthrough drill for the mount screws on the same $8 freight, unless you have a #1-60 drill set already.
Scopes are limited to 80 v signals, or cost $600 up. I make do without one. I have a Simpson 266xlpm meter which goes down to 2.5 vac. I can see 50 mv on it. It has no electrolytic caps in it to expire and works still after 33 years. Of course dvm are handier for dc since the polarity doesnt matter, but they miss short pulses like loose solder connection pops and produce random numbers on music signals. The fluke RMS DVmeter stops at 7000 hz so ultrasonic oscillation is invisible. Caught some in an op amp circuit with the Simpson 266. Use a .047 uf capacitor (400 v) series negative probe to block DC from showing up on AC scale. If a signal exists, you can't hear it, and it still passes through a 390 pf blocking capacitor, it is an ultrasonic.
I've quit working since 2008, when I had only a FM radio with a 2" speaker working. I now have stereo 70w/ch in my music room with 2000 LP's and SP2-XT speakers, stereo 125 w/ch with the HDTV with 6" coaxial speakers in newark boxes, and mono 30 w/ch with 2 way 15"+horn wedge monitor in my summer trailer. All amps repaired/improved by me from the glory days of US production. Plus 2 hammond H100 organs working and 2 working pianos.
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If you’re using Ethernet cable, load it in 82 or 100 ohms, whichever resistor is on hand. Shielded twisted pair is “approximately” 93 ohms. Matching isn’t important if the signal isn’t broad band, but the lower the Z the less induced hum you can have in an unbalanced twisted pair. There will be tens of ohms in the wire. Even 3 of these in parallel will be an easy load for a small amp, about perfect for a headphone amp, but a bit taxing for a cheap mixer (expensive one no problem). You could try increasing the load resistor value to 1k or even a few k, but eventually it will start humming. Of course you could equip the receiving ends with an op amp balanced input circuit, then you can run high impedance (about 10 to 20k) and anything will drive it. Cheaper than a decent transformer actually.
If You want to transmit digital SPDIF try a 2.4 or 5 GHz video transmitter & several receivers.
Connect the digital cables to the yellow Video RCA.
I've done it one time but the antennas are picky to align, unless You use some sort of dish.
On a wedding farm I have 200m of mic cable buried feeding 5 boxes with XLR's and they work fine for balanced line signals. If Your gear hasn't balanced outs, there are cheap converters available.
But ... I believe You want to go the digital streaming route where You transmit various signals from various locations and then select at each location which channel You want to hear. There are solutions but $$$$
Connect the digital cables to the yellow Video RCA.
I've done it one time but the antennas are picky to align, unless You use some sort of dish.
On a wedding farm I have 200m of mic cable buried feeding 5 boxes with XLR's and they work fine for balanced line signals. If Your gear hasn't balanced outs, there are cheap converters available.
But ... I believe You want to go the digital streaming route where You transmit various signals from various locations and then select at each location which channel You want to hear. There are solutions but $$$$
Hmm I just found a couple of those on the top shelf, Glad I didn't toss them with the onset of video over 480x600 and Svideo
I definitely thought about how they might do the job. I also have an Omni DMS-1 that I never installed into my truck, and I think it might be able to use the wifi but I only have the one receiver and the 20 gig vehicle unit . You are right, I would love the ability to control each of the 18 channels individually , Imagine a set of songbird tracks I might rotate around the property to give illusions of real birds flying about.
$$$$ don't buy the sort of freedom that self innovation can and it just wouldnt be as satisfying. Hell I have been thinking about how I might have SPL meters strategically placed to auto trim the volume of outlying speakers and avoid violating the 65db at the street noise code. But you know how that goes, ill be happy to make it chooch with minimal sophistication.
I almost have enough primary research and inventory done to build out my central connection box and then Ill start experimenting with the methods suggested here. this project is entering its 20th year of development with lots of lulls, so many threads of technology and advances since I first laid out wires and my equipment and understanding has evolved as well. I am really grateful that I found this forum were I can find help from others who are like minded and have diverse backgrounds and experience.
Today's agenda is re foaming the kappa 6 without breaking anything while getting the benzyl off. To use toluene or alcohol to soften the glue or just knife it is the question. possible Cancer, and or melted cones or laceration and ER for stitches
wish me luck .
Well now my imagination has just gone silly, as I realized I have the infrastructure to go 2-way from each amp. ,
Got my first 10 inch kappa 6 all cleaned up pretty and laid the new foam on it to find out of 10 speakers I ordered for they were the only ones that were wrong. errrg as Bob Seger would say I had to turn the page, tonight I am going to start a batch of wine in this new fangle tapered fermenter.
Got my first 10 inch kappa 6 all cleaned up pretty and laid the new foam on it to find out of 10 speakers I ordered for they were the only ones that were wrong. errrg as Bob Seger would say I had to turn the page, tonight I am going to start a batch of wine in this new fangle tapered fermenter.
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