dagoose
Well-known member
And this is what the frontpanel will look like when done.
http://www.dagoosemusic.nl/diy/monitor/monitorheadphone.pdf
http://www.dagoosemusic.nl/diy/monitor/monitorheadphone.pdf
100% passive monitor control ideas
- Thread starter dagoose
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rob_gould
Well-known member
[quote author="dagoose"]And this is what the frontpanel will look like when done.
http://www.dagoosemusic.nl/diy/monitor/monitorheadphone.pdf[/quote]
Very nice - the whole project looks really good :thumb:
http://www.dagoosemusic.nl/diy/monitor/monitorheadphone.pdf[/quote]
Very nice - the whole project looks really good :thumb:
dagoose
Well-known member
Allmost done!
Time for some pictures
There are some minor things i have to change but it's allready up and running :wink:
I will post more info and pics of the guts ASAP.
Time for some pictures
There are some minor things i have to change but it's allready up and running :wink:
I will post more info and pics of the guts ASAP.
Harpo
Well-known member
congrats :thumb:
Did you end up with single rail voltage for headphone amp, relais and led ?
Did you end up with single rail voltage for headphone amp, relais and led ?
dagoose
Well-known member
[quote author="Harpo"]congrats :thumb:
Did you end up with single rail voltage for headphone amp, relais and led ?[/quote]
I used a 2x 15v transformer, 1 output is used for the relays and leds and the other one is used for the headphone amp.
The relays are just activated when you push a button for let's say, mute, it's in rest when not pressed.
Ofcourse the input realys are activated with active input and when switched to monitor B it's also activated but most relays are not powered in normal use, even the relays for the 2 color leds are just in use when a button is pushed.
As you can see all audio signal relays are as close to the XLR's as possible to keep the wires as short as possible and to avoid the audio being crossed by a voltage line, even the relayscoils are as far away as possible.
The relays in front are for switching the leds and the voltage lines for the headphone amp and from one board to the other are mounted on the bottom of the case just behind the frontpanel.
The headphone amp is a single 5532 opamp powered with about 2x7.5v with a resistor divider network and works perfectly!
The only thing i have to change is the level pot, it's on the output right now and i used a log pot which should be a rev log or lin pot, now only the last part of the pot is taking care of the level making it hard to get the right level.
Maybe i'll also put the pot on the input instead of the output because when the input is loud i get a slightly distorted sound, the output itself is very LOUD and clean so that is not the problem.
Input 3 has a 12steps attenuator (unbalanced) connected to the input for tuning, this input i use directly from the soundcard ouput for mastering.
For the rest i'm really happpy with the result, it works great, sounds great (doesn't sound at all that is..) and it looks even way better then i expected it to look!
I will post some inside pics and clearer pics of the frontpanel later on.
Did you end up with single rail voltage for headphone amp, relais and led ?[/quote]
I used a 2x 15v transformer, 1 output is used for the relays and leds and the other one is used for the headphone amp.
The relays are just activated when you push a button for let's say, mute, it's in rest when not pressed.
Ofcourse the input realys are activated with active input and when switched to monitor B it's also activated but most relays are not powered in normal use, even the relays for the 2 color leds are just in use when a button is pushed.
As you can see all audio signal relays are as close to the XLR's as possible to keep the wires as short as possible and to avoid the audio being crossed by a voltage line, even the relayscoils are as far away as possible.
The relays in front are for switching the leds and the voltage lines for the headphone amp and from one board to the other are mounted on the bottom of the case just behind the frontpanel.
The headphone amp is a single 5532 opamp powered with about 2x7.5v with a resistor divider network and works perfectly!
The only thing i have to change is the level pot, it's on the output right now and i used a log pot which should be a rev log or lin pot, now only the last part of the pot is taking care of the level making it hard to get the right level.
Maybe i'll also put the pot on the input instead of the output because when the input is loud i get a slightly distorted sound, the output itself is very LOUD and clean so that is not the problem.
Input 3 has a 12steps attenuator (unbalanced) connected to the input for tuning, this input i use directly from the soundcard ouput for mastering.
For the rest i'm really happpy with the result, it works great, sounds great (doesn't sound at all that is..) and it looks even way better then i expected it to look!
I will post some inside pics and clearer pics of the frontpanel later on.
matthias
Well-known member
very nice...
I really like that color of the front panel... is that "mid bronze" from schaeffer-ag ?
I can't see any protection diodes for the relais...
did you modded that switches or are these available in these colors...?
I really like that color of the front panel... is that "mid bronze" from schaeffer-ag ?
I can't see any protection diodes for the relais...
did you modded that switches or are these available in these colors...?
Sweet switcher!
I second the de-bouncing diodes for the relays. Are they under the board? If not, add them and the unit will sound MUCH tighter when switching.
I use a reverse-biased 4001 diode on each relay coil.
Mike
I second the de-bouncing diodes for the relays. Are they under the board? If not, add them and the unit will sound MUCH tighter when switching.
I use a reverse-biased 4001 diode on each relay coil.
Mike
dagoose
Well-known member
[quote author="matthias"]very nice...
I really like that color of the front panel... is that "mid bronze" from schaeffer-ag ?
I can't see any protection diodes for the relais...
did you modded that switches or are these available in these colors...?[/quote]
Yep, it's schaeffer mittelbronze! I like the color to, i think it makes it look pro!
The switches are standard swithes i 'allways' use, they have a white cap, they normally have a 12v standard bulb of 3mm but a 3mm led also fits so i insterted a 2color led and the whole switch is red or green
About the diode on the coild aof the relays, do they switch faster that way or what is the purpose?
Do you connect it the way as in the schematic below?
I think a 4148 diode will do fine then is it?
I really like that color of the front panel... is that "mid bronze" from schaeffer-ag ?
I can't see any protection diodes for the relais...
did you modded that switches or are these available in these colors...?[/quote]
Yep, it's schaeffer mittelbronze! I like the color to, i think it makes it look pro!
The switches are standard swithes i 'allways' use, they have a white cap, they normally have a 12v standard bulb of 3mm but a 3mm led also fits so i insterted a 2color led and the whole switch is red or green
About the diode on the coild aof the relays, do they switch faster that way or what is the purpose?
Do you connect it the way as in the schematic below?
I think a 4148 diode will do fine then is it?
radiance
Well-known member
[quote author="dagoose"]
About the diode on the coild aof the relays, do they switch faster that way or what is the purpose?
[/quote]
Less switching noise...less clicks when switching. It also acts as a protection for other components down the line, such as transistors, but in your case that's not very important I guess...
see this link. scroll down a bit.
http://www.kpsec.freeuk.com/components/relay.htm
[quote author="dagoose"]
Do you connect it the way as in the schematic below?
I think a 4148 diode will do fine then is it?
[/quote]
Yes & Yes
About the diode on the coild aof the relays, do they switch faster that way or what is the purpose?
[/quote]
Less switching noise...less clicks when switching. It also acts as a protection for other components down the line, such as transistors, but in your case that's not very important I guess...
see this link. scroll down a bit.
http://www.kpsec.freeuk.com/components/relay.htm
[quote author="dagoose"]
Do you connect it the way as in the schematic below?
I think a 4148 diode will do fine then is it?
[/quote]
Yes & Yes
radiance
Well-known member
How did you do the mono summing? Can't see any active circuitry for that on your pics....Only opamp I see is from the headphone amp right?
dagoose
Well-known member
[quote author="radiance"]How did you do the mono summing? Can't see any active circuitry for that on your pics....Only opamp I see is from the headphone amp right?[/quote]
Yes, i did passive mono summing here, i didn't hear any disadvantages while testing it so i left it that way.
Maybe later on i'll go for a active mono summing but for now it's OK
I'm also busy rebuilding my studio in the new place so that DIY part comes first now, pics soon. :green:
Yes, i did passive mono summing here, i didn't hear any disadvantages while testing it so i left it that way.
Maybe later on i'll go for a active mono summing but for now it's OK
I'm also busy rebuilding my studio in the new place so that DIY part comes first now, pics soon. :green:
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