Mod for HRDlx Power Amp In

[alfonso]

Hi,
As probably most of you know if you plug a cable in the PreAmp Out of a Hot Rod Deluxe it works like a split capable to send the sound somewhere else but the internal connection with the power amp keeps working unaffected.

What really defeats the connection is plugging a jack in the Power Amp In.

What I would like to do is to add a switch to remove this "internal connection defeat" function if I want, allowing me to add a 100% wet delay output while the dry sound remains untouched and still travels inside to the power amp.

The reason i want to do so is because I love my Eventide Timefactor which allows a "killdry" function for full wet output, but despite the high quality I don't like what it does with its buffer if I use it in relay bypass mode (that also has the drawback to cut the delays when the unit is switched off) and even less to keep the signal constantly digitized if i use it in dsp mode.

In another amp, a 5e3, I used it very nicely grabbing the guitar sound from one of the secondary inputs and sending it to the other input, i also have independent volumes...I think that having the possibility to use the preamped signal in the hot rod's fx loop is even better, but only the way I described above.

Please enlighten me on what could I do. I don't care if I have to mod heavily the hrd, it's already very modded and really kicks, so...

Thanks.

[Enzo]

I guess I don;t understand your question. You say the stock amp has a connection that continues on to the power amp wwhen you use the FX send by itself. Then you say you want to mod the amp so it can send a signal out the FX send but still have the unaffected signal continue on to the power amp. Isn;t that what it does now? Are they not the same thing? What am I missing?

If you want to defeat the FX loop with a stomp switch, get a relay and steal the circuit from something like a PV 5150. It is a simple a relay scheme as it gets.

[alfonso]

I guess I don;t understand your question. You say the stock amp has a connection that continues on to the power amp wwhen you use the FX send by itself. Then you say you want to mod the amp so it can send a signal out the FX send but still have the unaffected signal continue on to the power amp. Isn;t that what it does now? Are they not the same thing? What am I missing?

If you want to defeat the FX loop with a stomp switch, get a relay and steal the circuit from something like a PV 5150. It is a simple a relay scheme as it gets.

Thanks Enzo. You missed the part where I say "What really defeats the connection is plugging a jack in the Power Amp In"

I want the fx loop to keep working while the internal path of the signal from the pre to the pwr is not interrupted. That way I can use the fx loop return to feed only the wet signal (digital with the Eventide) while the dry signal doesn't go through the fx loop but keeps flowing internally like there wasn't anything attached to the power input. I'd like to achieve this with a switch so I can decide for standard serial or "parallel" operation.

[Enzo]

If he jacks are connected together still, you can;t "mix" signals by just cramming them together. You need a mixer, either external or build one into the amp.


You could try to mix them old Fender reverb circuit style. Replace the connection between the jacks with a large value resistor, so the send is taken off one end and the return comes back to the other. Not sure how well that would work without a recovery stage.

Most of the companies that make PA stuff make little palm sized mixers with 2,3,4 channels. Not expensive. Run your send to that, and from that to your effect and back, then you can mix both dry and wet signals and send that back to the return. No amp mod required.