Reactive Load/Line Out

[PLX]

I used Aiken's reactive load ideas as a starting point to build this.

It's a 500W, 16Ω reactive/resistive load with a Jensen audio transformer line out, ground lift circuit and cooling fan.

This allows for silent recording, dummy load test bench work on an amp, as well as a line-level signal into a recording interface for impulse responses such as cab/mic sims.











schematic:

[RockyStar]

You make all kinds of cool stuff and I cringe at having to replace pickups...lol.

I need to up my game.

[Monkey Man]

Indeed. Brilliant, PLX!

[harddriver]

Nice, Transformer isolated line out. That is a nice load/line out box. It reminds me of the Jose load/line out box that Mark Cameron has.

I built a 400 watt load box using 4 100 watt Arcol load resistors in series/parallel like a speaker box, I couldn't get a good line out design so I ended up using the Suhr iso/line out pretty much akin to the Jensen transformer isolated line out that you have used here and that make all the difference in the world for tapping the line level signal for effects/reamping/W/D/W, IMHO.

That's great load box PLX...............................Quite impressive...

[PLX]

Nice, Transformer isolated line out. That is a nice load/line out box. It reminds me of the Jose load/line out box that Mark Cameron has.

I built a 400 watt load box using 4 100 watt Arcol load resistors in series/parallel like a speaker box, I couldn't get a good line out design so I ended up using the Suhr iso/line out pretty much akin to the Jensen transformer isolated line out that you have used here and that make all the difference in the world for tapping the line level signal for effects/reamping/W/D/W, IMHO.

That's great load box PLX...............................Quite impressive...

Thanks man!

I started off with simple resistive loads, like the one Mark Cameron posted to metroamp back in the day..




In the beginning, I used a purely resistive load and an audio transformer for the line out.

[harddriver]

I also initially tried just loading down the head thru the resistive load, it didn't suck... but I find I got a better tone when using it in parallel... so I agree with your assessment of the just a resistive load being used singularly sounding a bit flat maybe, it's been a while since I've heard it by itself but I know it wasn't ideal.

When running my 68 plexi I usually end up at 80-85 ACV, I've delved into the 65-75 ACV area and It was cool and all but I don't think it was the end all be all so YMMV with all this crazy Ed stuff....

I ended up using my 16 ohm 400 watt resistive load in parallel with my dry 16 ohm 4x12 cabinet of which I am going through a RIvera Rockcrusher set to - 8DB to further dump some DB for house playing levels that doesn't color the tone. The resistive load in parallel helps dump some DB energy so essentially it is a Resistive/Reactive load just done a different way, I can dump quite a bit of volume this way and still have a great uncolored signal. I find just about any Attenutaor beyond -8 DB really starts affecting the tone and feel of course this is due to with the Fletcher/Munson curve blah blah blah....

Randall Aiken definitely knows his shit, he ranks right up there with Larry for amplifier knowledge!

The toothless Jose sombrero Ed pic is quite classically irreverent BTW!

[PLX]

I also initially tried just loading down the head thru the resistive load, it didn't suck... but I find I got a better tone when using it in parallel... so I agree with your assessment of the just a resistive load being used singularly sounding a bit flat maybe, it's been a while since I've heard it by itself but I know it wasn't ideal.

When running my 68 plexi I usually end up at 80-85 ACV, I've delved into the 65-75 ACV area and It was cool and all but I don't think it was the end all be all so YMMV with all this crazy Ed stuff....

I ended up using my 16 ohm 400 watt resistive load in parallel with my dry 16 ohm 4x12 cabinet of which I am going through a RIvera Rockcrusher set to - 8DB to further dump some DB for house playing levels that doesn't color the tone. The resistive load in parallel helps dump some DB energy so essentially it is a Resistive/Reactive load just done a different way, I can dump quite a bit of volume this way and still have a great uncolored signal. I find just about any Attenutaor beyond -8 DB really starts affecting the tone and feel of course this is due to with the Fletcher/Munson curve blah blah blah....

Randall Aiken definitely knows his shit, he ranks right up there with Larry for amplifier knowledge!

The toothless Jose sombrero Ed pic is quite classically irreverent BTW!

Exactly. I run this connected to one 16Ω tap and the other 16Ω tap into my 4x12 cab.

What it does it drop the volume by about one third, and it gives you a line-level signal out.

I'll mike up the 4x12 (Scumback BM-75) with an SM-57.

The line-out signal goes into my audio interface and then thru an impulse response of a JBL-D120 speaker mic'ed 1" away, and on center. Then I mix these two signals in my DAW.