useful little tool for setting gains...

[toaster 10+ year member]

get a pair of headphones, and then goto radioshack and buy an adapter to convert the 1/8 plug on the end of them to stereo rca connectors. either that, or hack the end off of the phones and solder rcas onto the cable.

your done.

plug these into your hu's outputs, and find out the exact spot where your hu starts clipping. youll know youre there when it starts distorting.

you can use these the same way with any preamp-level processor.

this will allow you to get the maximum amount of CLEAN voltage to drive your amps input stages!

have fun, start soldering!

Click to read more...

 

[kotec123 10+ year member]

thanks for the post man!

 

[bikejunkie223 10+ year member]

Won't that garantee bleeding from the ears and deafness? I'm confused...is it because pramp output isn't high enough voltage to generate any volume to hurt?

 

[mikescanlon 10+ year member]

preamp voltage = 0.01-7 volts... amplifier output voltage = 35-100+volts

 

[toaster 10+ year member]

no, it prob wont get loud AT ALL, just loud enough to know when youre clipping.

 

[bikejunkie223 10+ year member]

cool, good idea.

 

[squeak9798 5,000+ posts]

What is the typical impedance of most generic headphones?

 

[JAZN 5,000+ posts]

What is the typical impedance of most generic headphones?

mine are 16ohms.

 

[toaster 10+ year member]

it varies. the one i have here just checked 37 ohms. its really not that important when doing this sort of thing, though, because most amps, as you already know, present several thousand ohms @ the input stage.

 

[squeak9798 5,000+ posts]

because most amps, as you already know, present several thousand ohms @ the input stage.

Exactly //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif The output impedance of the source is much much lower than the input impedance of the receiving component. Same thing with the output of amplifiers....very minimal output impedance vs. the (relatively) higher input impedance of the speaker (hence, damping factor)

Whereas most output impedances will be >100ohm for the source unit's preamp outputs, trying to drive a very low (relatively) input impedance of the headphones.

I'd prefer Dave Navone's method of a small powered speaker that can also typically be picked up at Radio Shack or the like for little $$.

 

[ndnbolla 10+ year member]

Setting the gains this way protects the subs right?

But does this method protect the subs too. What I am saying is that I have an amp that is going to power four eights at 1 ohm. However if I give the full potential (1200 watts total) of the amp towards the these 4 eights (only want 200watts each=800 total), it would likely be harmful to them.

What would be the best method of setting the gains in this setup.

 

[azbass 5,000+ posts]

i use a test light. .........

 

[toaster 10+ year member]

oooya squeak, forgot about the small speaker, it works well, also. either or is fine.

 

[bikejunkie223 10+ year member]

This is majorly interesting, never though about doing that....hmmm experiments!