Does any forum member have any project and pcb of a 5-band tone control that doesn't have a built-in preamp and that's stereo that you can share? frequency ranges from 50hz to 16khz?
I did build 5 band eq in the past, just line in, line out, it had only 3 transistors. I believe it was adopted from jvc circuit.
It was published in old commies magazine Amaterske Radio. I do have box of those magazines in the atic somewhere. I can look for it in few days.
Otherwise, if you go to hifiengine, there may be service manuals for 5 band eq. Including pcb. JVC had surprisingly simple circuits which sounded ok.
It was published in old commies magazine Amaterske Radio. I do have box of those magazines in the atic somewhere. I can look for it in few days.
Otherwise, if you go to hifiengine, there may be service manuals for 5 band eq. Including pcb. JVC had surprisingly simple circuits which sounded ok.
Sorry, if someday you find the magazine and post only the page of this project, it could be to my email anyway, if it isn't too much trouble. thanks
I have a Kenwood equalizer, they used different values of capacitors as frequency filters.
Very common in mid fidelity systems...
https://www.google.com/url?sa=t&rct...=G-7cK-DAbCw&usg=AOvVaw3T5QnKiGGlx30dzIleXn1q
https://www.google.com/url?sa=t&rct...zer-circuit/&usg=AOvVaw0yTND8iJJX1nupXW7AmJyn
https://www.google.com/url?sa=t&rct...c-equalizer/&usg=AOvVaw06b8JO203wcdmUh3sC9ThEhttps://www.google.com/url?sa=t&rct...circuit-for/&usg=AOvVaw0cO8FsKmZaLd1Uty7PyqQ0
https://www.google.com/url?sa=t&rct...th-4558.html&usg=AOvVaw1M6xIUsqf4LXGmrUjxwyeC
Have fun!
Very common in mid fidelity systems...
https://www.google.com/url?sa=t&rct...=G-7cK-DAbCw&usg=AOvVaw3T5QnKiGGlx30dzIleXn1q
https://www.google.com/url?sa=t&rct...zer-circuit/&usg=AOvVaw0yTND8iJJX1nupXW7AmJyn
https://www.google.com/url?sa=t&rct...c-equalizer/&usg=AOvVaw06b8JO203wcdmUh3sC9ThEhttps://www.google.com/url?sa=t&rct...circuit-for/&usg=AOvVaw0cO8FsKmZaLd1Uty7PyqQ0
https://www.google.com/url?sa=t&rct...th-4558.html&usg=AOvVaw1M6xIUsqf4LXGmrUjxwyeC
Have fun!
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Not one.
I have two separate equalizers, and three built in as part of the system.
And Winamp has it as part of the software.
I need not make one.
I have two separate equalizers, and three built in as part of the system.
And Winamp has it as part of the software.
I need not make one.
Sure no need to build, just that everyone can 'google', but the stuff on web is often misleading, even downright wrong.
See my thread about c5200/a1943 amp...
I am selling 31band behringer on ebay, have spare 15 band rane, just gave 7 band jvc to a friend, and i am keeping three behringer ultracurve 31 band for each system.
No need to build either, but i do build stuff for fun and to learn. When i make advice, its a stuff i know works. Otherwise advice is cheap.
See my thread about c5200/a1943 amp...
I am selling 31band behringer on ebay, have spare 15 band rane, just gave 7 band jvc to a friend, and i am keeping three behringer ultracurve 31 band for each system.
No need to build either, but i do build stuff for fun and to learn. When i make advice, its a stuff i know works. Otherwise advice is cheap.
I did design a spectrum analyzer using the circuit from my Kenwood graphic equalizer, that is where I learned about the circuit used.
The entire Kenwood system was donated to a Jesuit school, and it was given to me by the Father, as I had helped him do the lighting in his school.
It had been eaten by rats, I had to wash it before checking, it was working, and apart from a later STK replacement, works fine.
The STK failed more than a year later, after I was using it with a computer as source.
Father wanted a spectrum analyzer, linked to LED flood lights, for the auditorium, so I hit upon the idea for putting level indicators on each frequency band, and using the output to switch each large light, which was to be mains operated.
Problem starts there, the lights have latency, and are mains operated, so running so many wires was asking for trouble...20 watt LEDs in different colors, and 7 bands x ten LED each. That is 70 wire pairs! Or at least 71 wires, if I used a common neutral.
And it is an open stage , so rats and weather to worry about.
It got too complex for me, and nobody makes those here, so it was abandoned.
Now I think it can be put inside a tall box, with low voltage LEDs, the available lights are more various now, maybe I will use stop lights from cars.
But I stand behind my basic analysis, the sound is separated by frequency, the level of each frequency is controlled by the listener, and the output is joined.
And at least on the Kenwood set, the RC networks on each frequency were the only different part in each band, the rest were identical.
It is 7 bands, stereo, so 14 linear sliding pots.
So I can say I know a little about it...Talk is indeed cheap.
The entire Kenwood system was donated to a Jesuit school, and it was given to me by the Father, as I had helped him do the lighting in his school.
It had been eaten by rats, I had to wash it before checking, it was working, and apart from a later STK replacement, works fine.
The STK failed more than a year later, after I was using it with a computer as source.
Father wanted a spectrum analyzer, linked to LED flood lights, for the auditorium, so I hit upon the idea for putting level indicators on each frequency band, and using the output to switch each large light, which was to be mains operated.
Problem starts there, the lights have latency, and are mains operated, so running so many wires was asking for trouble...20 watt LEDs in different colors, and 7 bands x ten LED each. That is 70 wire pairs! Or at least 71 wires, if I used a common neutral.
And it is an open stage , so rats and weather to worry about.
It got too complex for me, and nobody makes those here, so it was abandoned.
Now I think it can be put inside a tall box, with low voltage LEDs, the available lights are more various now, maybe I will use stop lights from cars.
But I stand behind my basic analysis, the sound is separated by frequency, the level of each frequency is controlled by the listener, and the output is joined.
And at least on the Kenwood set, the RC networks on each frequency were the only different part in each band, the rest were identical.
It is 7 bands, stereo, so 14 linear sliding pots.
So I can say I know a little about it...Talk is indeed cheap.
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I think if I copy or adapt the circuit from a service manual, it will be easier.
I also think that if I make one for personal use, off a 40 year old model,the original company will not take it very seriously. Possibly think it a compliment.
I prefer to do it in software, simply because I have old sets, don't want to wear them out, and have noise issues from worn pots.
I also think that if I make one for personal use, off a 40 year old model,the original company will not take it very seriously. Possibly think it a compliment.
I prefer to do it in software, simply because I have old sets, don't want to wear them out, and have noise issues from worn pots.
Thanks for helping the good Father.
You bet.
Plus using mains, and in such a complex system is dangerous/crazy.
Funny thing is, you do not need mains at all.
Not at individual lamp level of course, you will still need a mains fed DC power supply to feed them all.
Commercial LED lamps have a built in SMPS feeding Led arrays some 30-40V DC.
Consider each array as "one" huge Led.
Pop bulb globe out, you´ll see the Led array sub-board plugged into the DC supply, measure voltage, you will need to disconnect Led array from individual supply and connect it to the light how display controller.
By the way, you will get rid of the "time delay" since you will be directly feeding each Led pack.
You can connect all anodes to DC supply positive, say +48V or whatever´s needed, to keep things simple each one through a current limiting resistor, and ground cathodes as needed through individual transistors.
Transistor bases are triggered from LM3915 or LM3916 Led meter drivers or some popular cheap equivalent, as used in Minicomponent or Karaoke amps. Ask your favorite supplier which ones does he stock.
OR go deeper into the rabbit hole, and design your own around LM339 comparators, each of them driving 4 Leds (through booster transistors of course).
Do NOT build controller at one place and run 71 long wires to display, but build/mount it inside the Led display box, there you will deal with short hidden wires only.
I bet a metal box will keep rats away.
🤣 you bet.
I had thought of putting LM3915 for each frequency band, stacked in two at a later stage, but for the first stage, 5 off, and using the outputs from the IC to control opto couplers, which would then control switching triacs / transistors on the high voltage side.
Now, I think I will get 12 Volt car lights, used as stop lights / truck tail lamp components (Red, Yellow, and White), and control them using the same scheme, only adapted to 12 V , from a maybe !0 A SMPS.
The latency comes from the drivers, they go through a sort of self test or whatever, so in a spectrum analyzer they will not be fast enough.
LEDs controlled from a common rail supply by switching elements will be faster to respond.
Will have to ask Father, he wanted spots or background lights, like the display in Winamp.
This will not have the same effect.
He will laugh, because this whole plan is about 10 years old, the high power LEDs, chip on board with a single connection, were new then. And reliable power supplies were an issue, they still are, lots of cheap stuff around in our country. Mains was the only way to get reliable high output LEDs to work.
Now things are different.
He may have changed his building, I have not visited him, in some time, since the Covid issue started.
Now, I think I will get 12 Volt car lights, used as stop lights / truck tail lamp components (Red, Yellow, and White), and control them using the same scheme, only adapted to 12 V , from a maybe !0 A SMPS.
The latency comes from the drivers, they go through a sort of self test or whatever, so in a spectrum analyzer they will not be fast enough.
LEDs controlled from a common rail supply by switching elements will be faster to respond.
Will have to ask Father, he wanted spots or background lights, like the display in Winamp.
This will not have the same effect.
He will laugh, because this whole plan is about 10 years old, the high power LEDs, chip on board with a single connection, were new then. And reliable power supplies were an issue, they still are, lots of cheap stuff around in our country. Mains was the only way to get reliable high output LEDs to work.
Now things are different.
He may have changed his building, I have not visited him, in some time, since the Covid issue started.
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I have put a picture of single mains fed LED on the last repair thread, I got it from the factory of a friend who assembles them from Chinese components, and sometimes asks for advice on how to do things.
I have access to his facility, and know how the lights are made, much more than most.
He makes bulbs, flood and street lights, and also sells panel lights, and I have sold a lot as a trader for him.
And I have watched the evolution of these lights, as the design and materials were updated, at the shop floor level.
I have access to his facility, and know how the lights are made, much more than most.
He makes bulbs, flood and street lights, and also sells panel lights, and I have sold a lot as a trader for him.
And I have watched the evolution of these lights, as the design and materials were updated, at the shop floor level.
Did the project long long time ago with optocouplers and tyristors. Easy control of mains light by music signal. It was not exactly spectrum analyzer, something similar, but more like disco music light effects. Pretty safe. You sure talk a lot.