Dummy Load for Recording

[EvolLove13]

I know this has probably been posted a few times here before, but I want to make sure that I am building this correctly so I don't ruin my tube head. I have four 4ohm 100W resistors that I have wired up like speaker cab, parrallel/series, which is then wired to a speak-on jack. Seems simple enough but wanted some input before I take it into the studio.

 

[seamonkey]

Follow that with a hook up a DI that can take an amps output/speaker load and convert it to line levels.

What your doing will not hurt and amp. Amps are always tested with resistors as dummy loads.

Keep in mind a real speaker has an impedance curve that changes with frequency. An amplifier with more resistance in series with it's output will tend to follow this impedance curve. This is part of the "tone" that some amp enthusiasts may be talking about.

 

[EvolLove13]

Thanks for the response, and I figured that it would be slightly different, I am just hoping that when I hook up through my DI out one my head that it sounds like I expect.

 

[Gideon352]

Just be aware that the resistors are going to get super hot. I'd mount them to a heat sink (IMHO).

 

[Bassamatic]

Yes - there are a lot of things that will be different using a pure resistive load - the impedance will be constant, there will be no back EMF, etc., although if they are wire wound resistors there will be an inductive component. It will be interesting! I hope you let us know the results of your experiment.

Hopefully you are using the type of resistors designed to be mounted to a heat sink, as they WILL get quite hot as mentioned above.

 

[seamonkey]

Link Removed
Talks about water heater elements for dummy loads. A twist in heater element can be had for $10
It can be mounted in a can filled with mineral oil
To find the ohms get the voltage and power (wattage) rating of the element and plug it into an ohms law calculator
Ohms Law Calculator

For example a 1500w 120v heater element is 9.6 ohms
a 1800w 120v would be 8 ohms

Instead though Taking just the DI out is 99.999% of the amp tone. Just be sure the amp part is not getting a signal if there is no load.

 

[fokof]

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