Hello all
I have a bunch of audio boards coming in, and I will be building a couple of complicated multichannel systems as well as updating my car sound with some pretty intricate builds and installation. I have ordered CNC, laser and 3d printing equipment for this project
I need to set up an audio bench to measure and monitor the projects. Current interest:
Test load
Is it a good idea to series parrell a whole bunch of 10w resistors to build some 250w 8ohm loads for further combinations to test for 4 or 8 ohms up to 1kw?
I have a bunch of audio boards coming in, and I will be building a couple of complicated multichannel systems as well as updating my car sound with some pretty intricate builds and installation. I have ordered CNC, laser and 3d printing equipment for this project
I need to set up an audio bench to measure and monitor the projects. Current interest:
- Power supply meters for voltage and current
- Amp output meters for power
- Amp output sine wave display
- Amp frequency response display
- Speaker driver parameter measurement
- Completed speaker frequency response graph
Test load
Is it a good idea to series parrell a whole bunch of 10w resistors to build some 250w 8ohm loads for further combinations to test for 4 or 8 ohms up to 1kw?
Well the sky is the limit (literally).
I have a 8ohm 100W planar resistors for my test loads - the same could be done for higher power just remember to heatsink them.
Audio analyser will best categorise your audio.
Oscilloscope is useful for peak and time based issues.
Two multimeters with probe kits probably want to check their max current if you’re using low voltage but high power.
Signal generator including sweep for bode plots.
I have a 8ohm 100W planar resistors for my test loads - the same could be done for higher power just remember to heatsink them.
Audio analyser will best categorise your audio.
Oscilloscope is useful for peak and time based issues.
Two multimeters with probe kits probably want to check their max current if you’re using low voltage but high power.
Signal generator including sweep for bode plots.
If we assume a resistor with a fixed resistive value of 100 Ohms, passes a current of 0.5 amperes (500mA), then the power dissipated by it will be, from Ohm's Law, P = I2R = 25 watts, which is equivalent to 25 joules of work per second.
My budget for this is fairly tight for now. I have located some items that I would appreciate some feedback on as to unsuitability
Load resistors (If I order 4x 8 ohms 500w then I can test all the boards I have on order)
Scope (I hope this is enough to see things like clipping point)
AC Volt meter (maybe I can use this to monitor the tube high voltage and current without using up multimeters)
DC Volt meter (haven't located one similar to above that has current too, again to free up multimeters)
2nd Multimeter (this one for things like amp speaker output voltage)
1st Multimeter (already have this, don't know of its capabilities for what I am doing)
Audio tool (looks comprehensive, but I can't read the language. I haven't looked at other options yet)
Signal generator (haven't picked one yet)
Load resistors (If I order 4x 8 ohms 500w then I can test all the boards I have on order)
Scope (I hope this is enough to see things like clipping point)
AC Volt meter (maybe I can use this to monitor the tube high voltage and current without using up multimeters)
DC Volt meter (haven't located one similar to above that has current too, again to free up multimeters)
2nd Multimeter (this one for things like amp speaker output voltage)
1st Multimeter (already have this, don't know of its capabilities for what I am doing)
Audio tool (looks comprehensive, but I can't read the language. I haven't looked at other options yet)
Signal generator (haven't picked one yet)
One option is use a Dilligent Analogue discovery - perhaps less rugged than a traditional scope but combines alot (see @stephe use one in her YT chanel).
That needs a computer but would combine scopw, audio analyser and sig gen in one IIRC.
https://digilent.com/shop/analog-di...ope-logic-analyzer-and-variable-power-supply/
That needs a computer but would combine scopw, audio analyser and sig gen in one IIRC.
https://digilent.com/shop/analog-di...ope-logic-analyzer-and-variable-power-supply/
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Perhaps better thinking of this as a journey.
I’m only a little way down the same road:
Recently i got two bench switched mode power supplies which have been useful.
More important is knowledge.
I’m only a little way down the same road:
- no name multimeter #1 - AC/DC voltages, mA & 10A, ohm and 600V limit.
- no name multimeter #2 - AC/DC voltages, mA & 10A, ohm and 1KV limit.
- probe pack 1KV with clipon leads
- scope - branded DSO up to 300Vpp on front ends. Useful for waveform, volt and FFT, plus blode plot.
- sig gen - a python program to listen to the scope bode plot and then control a pitch out of the headphone jack. 10-20Khz only but works well enough.
Recently i got two bench switched mode power supplies which have been useful.
More important is knowledge.
Sorry - i got the name wrong - analogue explorer. Perhaps expensive but may do alot more than your seperate compoents.
A good multimeter is worth it.
Note you need additional bits for the analogue explorer such as bnc adaptor and probes I think. Note it will not do the high voltages a traditional scope and do). Plus having an adaptor board would be a safety issue even if it could.
An old analogue scope may be a good option if you can find one in good shape and calibrated.
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the issue with all the little display scopes (ie the aliexpress specials) is they’re not worth wasting your money on. Half the time the triggering is in software and inaccurate.
Makes sense, I am versed with things like water cooling. I could try exploring a water jacket type sink arrangement with fans, like CPU cooling gear
Do you mean the lil volt meter things? Or the budget multimeter?
Thanks for taking and interest and the tips
I’ve been weighing up if a sig gen or ADC (such as scarlett solo) would be my best next step.
A sig gen would allow le to tune radios but at the moment my python program works for bode plots.
An ADC would offer a better FFT and better noise level compares to the 8bit scope. (Scope - think speed and time, an audio analyser think depth and frequency). I and see faster stuff with the scope which is useful, and can see waveforms etc but it has a limited resolution due to the 8bit ADC in it. The audio analyser - specifically a soundcard in my case would allow 24bit up to 192Ksps. Better for amp FFT as the dynamic range and noise floor is better.
I will need to add some form of voltage divider to reduce the voltage down to the input level of the ADC.
A sig gen would allow le to tune radios but at the moment my python program works for bode plots.
An ADC would offer a better FFT and better noise level compares to the 8bit scope. (Scope - think speed and time, an audio analyser think depth and frequency). I and see faster stuff with the scope which is useful, and can see waveforms etc but it has a limited resolution due to the 8bit ADC in it. The audio analyser - specifically a soundcard in my case would allow 24bit up to 192Ksps. Better for amp FFT as the dynamic range and noise floor is better.
I will need to add some form of voltage divider to reduce the voltage down to the input level of the ADC.
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