how easy would it be to intergrate a real time meter for each channel
i guess you wouldnt be able to use the speaker output directly as it would drag the output down?
i want to experiment with an old amp i have that i dont mind messing around with the from to insert an led array or a couple of db/vu meters on the front panel with the view to doing a realy good proffesional modification to one after one i have done a successful test mod.
i guess you wouldnt be able to use the speaker output directly as it would drag the output down?
i want to experiment with an old amp i have that i dont mind messing around with the from to insert an led array or a couple of db/vu meters on the front panel with the view to doing a realy good proffesional modification to one after one i have done a successful test mod.
It is simply a high impedance voltmeter calibrated in VU or dB.
The input can be taken from pre amp out, that means from the input to the power amp section.
High impedance should not affect the amp performance, as the signal draw will be small.
IC based kits, with bar graph and sometimes hold function, are available, in steps of 5 or more LEDs.
School kid level stuff.
Or find old VU meters, or use an analog meter in 0-10 ACV scale, keep them outside and see how they dance around.
Careful with the connections, a small short and you may have a bigger job on your hands.
The input can be taken from pre amp out, that means from the input to the power amp section.
High impedance should not affect the amp performance, as the signal draw will be small.
IC based kits, with bar graph and sometimes hold function, are available, in steps of 5 or more LEDs.
School kid level stuff.
Or find old VU meters, or use an analog meter in 0-10 ACV scale, keep them outside and see how they dance around.
Careful with the connections, a small short and you may have a bigger job on your hands.
There are a lot of boards for VU meters (analog and LED) on eBay and Aliexpress. Though, there are LED VU meter boards which got an AGC (automatic gain control), that's nice for show but they say nothing about what's really going on.
Yes, that's what I assumed. I just wanted to mention you can get what you want but there are boards which are - just what you said - 'christmas trees'. Just read the description or the print on the board. You can of course build it completely on your own but at the prices of the chinese boards you often don't even get half of the parts.
Very easyly done. Having some analog VU-meters in my cupboard, I built one around an opamp - any will do - and a CD4538 for peaks vizualiation. As it was for a studio tape recorder, I added a gain selector (0,-10,-20,-30dB) and associated adjustment trimmers for sake of precision. I first built a protototype on a test board. As it worked as expected, I had a PCB made. See construction here.
As said by AIM65, an LM3915 will do the trick perfectly
i do have one of these but you have to plug it into an output.
i tried it in series with the pre amp but you have to turn it up untill the neighbours go out before it works
each of these devices should have buffer/its own preamp in front of them not to load your signal
there was another thread here where member had preamp with high output impedance, and when he attached VU meter, it lowered the signal
simple jfet buffet, ot even better jfet with bjt pre would do
I have lots of VU meters, analog, led based, fluorescent vacuum based, tube based, I love this stuff
cheers!
there was another thread here where member had preamp with high output impedance, and when he attached VU meter, it lowered the signal
simple jfet buffet, ot even better jfet with bjt pre would do
I have lots of VU meters, analog, led based, fluorescent vacuum based, tube based, I love this stuff
cheers!
"how easy would it be to intergrate a real time meter for each channel
i guess you wouldnt be able to use the speaker output directly as it would drag the output down?"
no, the power output will not mind...you can connect it directly
your power (vu) meter should have some trimmer to adjust the sensitivity
ideally switch to adjust high and low sensitivity
i guess you wouldnt be able to use the speaker output directly as it would drag the output down?"
no, the power output will not mind...you can connect it directly
your power (vu) meter should have some trimmer to adjust the sensitivity
ideally switch to adjust high and low sensitivity
I would like to know where would you install the led or meters on the front panel.
there seems to be not enough space for the meters,
for led, how would you arrange the place for the installation.
there seems to be not enough space for the meters,
for led, how would you arrange the place for the installation.
Instead of cutting up that nice case, make one in acrylic and put it on top.
A strip running the whole width in wood or acrylic, height and depth to suit, in matching color.
A strip running the whole width in wood or acrylic, height and depth to suit, in matching color.
above the volume control,one this they would need to be a couple of LED bars or on another amp, maybe an older one like the way they are fitted on the 3030 that has power meters
Dorrough A40.
Peak and RMS displayed simultaneously.
Schematics for early units on website.
Dorrough Loudness Monitor Model 40-A - YouTube
Peak and RMS displayed simultaneously.
Schematics for early units on website.
Dorrough Loudness Monitor Model 40-A - YouTube