Slaving...best way to effectively load amp

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PaulP

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Hello Dave and Company,

So been snooping around here and have picked up a ton of useful info. I am running an older stock 73 NMV Marshall into a 4x12 cab. I was turned onto the whole W/D thing a while back from a few friends but never got around to actually putting into practice. But to facilitate the concept I had Hu Kong Ho (guy that actually makes the Ultimate Attenuator) build me an attenuator with an effects loop and the ability to run second cab. Basically I have been using an attenuator on my Marshalls for a long time but recently just rediscovered how much better (to my ear) is sounds without the attenuator plugged in at all. Even set wide open the attenuator just takes some of the sparkle/dynamics/magic away fro the overall sound. Plus I recently bought a Strymon Timeline that really seems to prefer being in the loop...as many of you know.

Soo, after doing some surfing I have really been digging into the idea of Slaving the Marshall into a power amp of some sort. Saw Pete Thorns vid where he did it. Been reading about for years but never tried it for who knows why....but the other day I did try it using my attenuator (taking it out of the effx send) and another amp. Went into the effx loop return so as to only use the power amp section. It works remarkably well! Better than any attenuator I have heard when actually clamping down on the volume. Plus in this fashion I can effectively use my time based effects (like i really have much..lol) and do a wet/dry thing if I want. Basically aside from the additional required gear and slight increase in complexity I think it's a much better way to make a NMV amp work. Plus gives me the ability to tie in effects and use either a 100W or 12W amp effectively.

Ok....so what is the best or most transparent way to put a dummy load on the amp prior to the going into the power amp? THD Hotplate? Faustine? Weber? DIY? Friedman Magic Box? I am open to opinions. Not factoring in cost at this point....always a factor of course but lets assume its all doable for the moment. As for Power Amps...seems like the Matrix is the current thinking. Unfortunately have to go on the experience and ears of others, but am open to suggestion. I can say definitively that the amp that I used as a "power amp" def did color and compress the tone. I actually heard the same "qualities" when slaving the Marshall as I did when playing the "other amp" solo. So that is not the answer "for me". But seems that a Solid State Power Amp is less inclined to compress and color things...as I understand it. Perhaps just a larger Power Amp that isn't pushed as much would also be viable...but now we are talk significantly more weight and expense....well weight anyway.

Currently I am leaning toward just going the Hot Plate set to load route down to line level...into Timeline....into power amp...into cab/cabs (if split wet/dry). One col thing about the Matrix it seems that it can handle a 4x12 (16ohm) on one side and a 2x12 (8 ohm) on the other without any drama. That would be cool!

Oh yea...not to open a can of worms but going back to the actual "loadbox".....any feeling on a "set" load vs resistive (like a speaker)? I think I asked that correctly? Anyway, any input and direction that can more effectively lead to a solid setup with the least drama would be great!

Thanks,
PaulP
 
If I understand what you're wanting (??) the best thing and most convenient to operate is the Suhr Line Out Box.

https://www.ebay.com/itm/NEW-Suhr-Iso-Li ... 337b6c7c97

No attenuator whatsoever as your Marshall & Speaker Cab won't even know they have anything plugged into them because they don't.

This is how the pros have been doing it forever.
 
That's not exactly what I am looking for. Yes it it absolutely preferable to no have to use an attenuator on an older Marshall in my opinion as it tends to color the tone in some way. In the case of mine it tends to kinda "throw a blanket over it". But but slaving out to a power amp (after the dummy load and reducing signal to line level) prior to the speaker cab should have significantly less impact on the tone of the amp with the added benefits of being about to insert time based effects after the Marshall (delay/reverb/ect), able to control the overall vol while still being able to completely saturate the power section of the amp, and be able to do the wet dry thing if you have a stereo power amp (and be able to control the vol independently if so desired.

Plus.....by setting it up in this fashion a second head could potentially be A/B for a different tone using same cab/effects if one of the higher end channel switchers were employed. Not necessarily gonna do that but it is just something else that could be done. I have been looking for years for the right way to make a nice vintage NMV amp work in smaller settings (local bars/clubs) but always ended up compromising and not being able to really run these things the way they were ment to be run....or at least I would like to run them (vbg). So the slaving thing, while a bit more complicated initially, seems like it might really be the answer. But it is dependent on a few variables...like the actual dummy load and the chosen power amp. Guys have slaved out to other amps for years but I dont want to mod an old amp that doesn't have a line out, line in, or effects loop. So....here we are.....looking for some input for others that have done it or have suggestions.

Pete Thorn's video was enough to get me motivated to finally give it a try.......

PaulP
 
If I understand what your are saying, you are asking what is the best way to load the amp and take a line level signal out for effect, etc and into what type of power amp.

Right?

There are several options. One it make a simply load box and line out ( See picture below), a 400 watt 16 ohm load box with a line out. Some argue that this colors the tone as well depending on the load, resistive (resittors) versus reactive (speakers). You could also use the attenuators you mentioned as long as they are designed to run as a load versus just as an attenuator.

In terms of the power amp, it seems that many look to the most transparent power amp possible. That is probably why Eddie Van Halen uses the H&H power amps for his set up.
 
I have tried many & they all color the sound in some way.
 
Yea....everything you guys are saying is pretty much how I understand it. The attenuators are likely the easiest method, but the one I currently have does color tone in a way that I think can be better......it just takes too much away from overall tone. Plus I keep hearing how this thing is not great for head in way it works. I dunno.

My understanding is that the Matrix power amps are pretty transparent and could be a good candidate for slaving. So....looking for the best way to give it a try. A dummy load would be good.....preferably a proven method that others have has success with.
 
Check out the Fryette LXII poweramp. There is a few videos on the Fryette YouTube page.

My favorite amp is my THD Series One Plexi .... a JMP built by THD. I have tried all kinds of methods for reducing the volume. Nothing sounds like the roar of the amp at full dB. I use a THD Hot Plate. I use it for attenuation & for lineout / slave rig. Both get good results .... but it is just physics it will never be the same.
 
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