|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
71.227.141.26
In Reply to: RE: Component values to configure a complex load for 8 ohm dummy resistor. posted by Duster on February 02, 2021 at 01:47:56
I think you might be surprised how much that could stress an amplifier. :) Pavel specifically notes, ".....torture tests."
However, regarding scaling the components, if you want the same frequency turnover point, then you would leave the capacitor value unchanged.
Dave.
Follow Ups:
What I actually seek is an 8 ohm dummy load that involves a level of reactance, not unlike the typical reactance that a loudspeaker produces rather than just the resistive load of the 8 ohm dummy load resistor. Maybe a more benign choice of values or another circuit altogether, without turning the project into a complicated and expensive circuit design. Stressing the dielectric of a cable placed between the power amplifier and 8 ohm dummy load is the goal, rather than stressing the output circuitry of the amplifier whatsoever.
Edits: 02/02/21
One thing to remember on the dielectric -
Most of the materials used have quite high tolerances for voltage leakage - even "low Voltage" wires, like Cat 6 cables, will not break down until the voltage is quite high....
Happy Listening
The application is intended to function as a more effective method to produce the initial burn-in process for a length of bulk audio cable than simply plugging the cable between two audio components, but less effective than a cable cooker provides. That's it, nothing more. Nothing to test, nothing to measure as a result of using the device.
The dummy load proposed by Pavel is much more reactive than a typical speaker load might present.
You need to rethink your goal. You'll be stressing the amplifier circuitry way before the dielectric of any connecting cable.
If you're interested in testing cable dielectric (and other aspects,) there is much better suited equipment for that.
Dave.
Thanks, Davey. A more basic resistive load for the purpose will make the application behave more like a line-level cable interface rather than a speaker-level cable interface, but if an amplifier-safe reactive aspect can't be included in the signal path without getting too complicated/expensive, I'll simply settle on a resistive load only.
Edits: 02/02/21
If you want to really test/characterize cables you need some specialized equipment. Hipot tester, megger, etc, etc.
You can't really do anything with an audio power amplifier and a dummy load.
Dave.
You are assuming I want to test something. Not the case at all.
You said you wanted to "stressing the dielectric of a cable placed between the........"
That's a test dude. :) And that's exactly what a hipot tester and similar equipment can do.
Dave.
It's not intended as a stress test. Nothing is being tested.
Davey, give up you've been "dusted". Testing, measurement and science are anathema to his audiophile beliefs.
It sucks to get old. It really sucks to get old and bitter.
Edits: 02/03/21 02/03/21
Yet another unfounded characterization of my audiophile interests, Uncle Mike.
You should pay more attention before attacking another AA Inmate in the forum.
check the link Duster ... intended for guitar amplifiers, but a speaker load is a speaker load
regards,
Yes, this looks more realistic. I was wondering about the lack of inductance in the other circuit.
Mike
a 'burn in' circuit with variable inductance / resistance = greater efficacy
IMO, Duster's reasoning is sound in his goals [pun intended]
with regards,
Thanks, rivervalley817. That's one of the circuits I considered among others I researched, but it's too complicated/expensive for the particular application. I'm configuring a cable burn-in device (not to be confused with a cable cooker) to provide higher voltage/current over a period of time than typical audio playback within a system, and wanted more than just a dummy resistor to use as the load. Perhaps I've been overthinking the application; not the first time mission creep became involved in a project.
a cheap heating pad might give you the circuit you want ... ; )
regards,
I need an audio signal for the purpose I have in mind, not just voltage and current, in and of itself.
you could use an audio signal, no problem
[now I'll make the obligatory 'warm sound joke']
it will imbue the treated cables with a warm sound
[I actually winced typing that too!]
with regards,
Since I'll be burning in a 50 foot length of bulk cable, sometimes up to 100 continuous feet at a time, I may achieve enough inductance by simply coiling the cable up like an air core inductor, and attaching the dummy load at the end.
that's a plan!
jeez, what the heck are you wiring?
regards,
A field recorder into a sound mixer, into a 200 watt at 8 ohms amplifier, out through the cable into an 8 ohm dummy load resistor.4G of audio burn-in tracks played on repeat for a few days should do the job. That way only the solder joints of the finished interconnect cables will need to see initial burn-in time.
Edits: 02/03/21
you're a mother of invention ... so to speak
I'll await your report on the project, sounds cool!
regards,
Only thing left is to affix a dummy load resistor upon a massive aluminum heatsink with whisper fan, with hope that the ATI Amplifier Technologies power amp can hold-up to the strain.
for burn in I'd take it to 16ohms ... it won't hurt the amp
don't get carried away with the volume knob, but still, it shouldn't
regards,
I'll look into using a multimeter to monitor the output level, and make sure there is plenty of overhead to keep things safe and sane.
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: