FX loops coming to Metro.

[axeman]

Traditional nomenclature for electronics would suggest using the designer's last name followed by the type of circuit in question. Linkwitz-Riley crossover, Butterworth filter, Williamson amplifier, Schmitt phase inverter, Perkins EQ, etc., etc.. In keeping with that, I think it's easy to call it a "Miller Loop." Not to be confused with the Miller Effect.

Steve is a great guy and has contributed a hell of a lot, both to this forum and, I am sure, amp enthusiasts all over. He doesn't deserve some fancy, catchy zip-zam-zoom name; he deserves better. A simple, no nonsense name. Just my opinion.

I agree +1. Steve has educated me on a lot of circuit problems, and up grades, and always took the time to explained technical stuff, so I can understand it, I even offered to donate money to his web site and I believe he said, “You don’t have to”. That’s one awesome DUDE.

Thanks Steve



Axeman

[marT]

Is that a picture of my loop on the store website? AWESOME!

[VelvetGeorge]

That is the pic Steve gave me. I think was titled "MarT Loop" or something like that. Hope that's OK.

Steve is the best, no question. Always happy to share info and help people out. I couldn't be happier than to be working with him on this.

VG

[SDM]

Yep that Martin's loop that he installed in his Metro 45. I sent those pics to George to show the general JTM45 install location/plan as MarT was the first to install/test one in a in a 45. Also hope that's okay it ended up in the store Martin, sounds like you don't mind though .

[IloveMyMarshall]

Yep that Martin's loop that he installed in his Metro 45. I sent those pics to George to show the general JTM45 install location/plan as MarT was the first to install/test one in a in a 45. Also hope that's okay it ended up in the store Martin, sounds like you don't mind though .

Boooooooo Yaaaaaaaaa!! I been waiting on this one, excellent and thank you! George do you have a global mail system where as when new products hit your store we get an e mail??
Hey Steve man hows the health? Hope all is well brother! And thanks again for all the schooling!!
ILMM

[marT]

Yep that Martin's loop that he installed in his Metro 45. I sent those pics to George to show the general JTM45 install location/plan as MarT was the first to install/test one in a in a 45. Also hope that's okay it ended up in the store Martin, sounds like you don't mind though .

Thats totally fine with me. Only I made a small error by soldering the resistor to the board for the B+ instead of using the strain relief hole for the lead and doing it the other way around. DOH! This is one of those things where it pays to read ahead in the instructions. It was really my stupid fault though.

[joshwilson3]

Steve's loop of doom...

[Tuco]

how would this compare to larry's loop?

I'm wondering this myself. I currently have Larry's loop in my Metro JTM45 and JMP50 builds, but this new one certainly would be less "bulky" for any future builds. But in the end, it's about tone. Anyone done a direct comparison?

[Krinkle]

Here's the name. The Miller Pedal Effects Loop, the MPFX Loop.

[Krinkle]

Steve/George,

This FX loop sounds killer. I have a question about it.

I plan on building a preamp using the exact same parts as I did when I built my 12XXX series. Same materials, same spacings, voltages, everything. I was wondering how I would verify that it was the same as what was inside my chassis. If I install an FX loop in my 12XXX and also in the preamp I should be able to send the signal out of the send on the preamp and into the return on the 12XXX series, correct? I should also be able to send other preamp signals into the return of the 12XXX, correct?

This way I can build 3 preamps, a Plexi, a 2203, and a Rocca, switch between them, and they should all sound like I crammed them into my 12XXX, correct?

Darrin

[SDM]

If the preamps are buffered to send out the appropriate signal level (around -20 to-10dbV as the loops do), then then you indeed could use the return of a loop in a 12XXX clone as a poweramp input for them.

May want to add a switchable MV to the 12XXX clone for optimizing master volume preamp use. Just switch it out when using a Plexi preamp, switch in when using a Rocco or 2203. Could also just put the buffer after the MV in the preamps themselves too, but you'll just minimize any noise of pedals or such that may be in the chain by adding the switchable master to the poweramp after the return of the loop - this really only applies if you like to play the MV amps quietly, masters turned well down.

Hope that made sense.

[bmf5150]

steve is the best,allways taking time to help others out...hes a great friend....

[Krinkle]

I just want to build a separate preamp that allows me to split the Marshall/Metroamp in half and add as little circuitry or coloring as possible, so I'm inclined to leave the Master Volume in the 2203 and Rocca preamps at the end of the EQ where it originally was.

I started by building a 12XXX, which allowed me to see how everything else besides the amp affected the tone, a very eye (or ear) opening experience, regarding the Marshall tone. I don't want to change a thing until I can hear how it affects the tone. I'm willing to do this one little thing at a time. This might not sound very progressive but my goal is to completely understand what affects the tone so I can get the 3 channels in a separate chassis but have it sound EXACTLY like I have 3 amps when what I have is 3 preamps and one power amp. No new tones just yet.

Every other schematic I've seen of this idea has some form of compensation/compromise like adding an extra tube stage on the input, sharing input stages, sharing a tube buffer stage at the end of the preamp chain, etc, that in my opinion changes the tone. If you go through a tube stage, you will add another order of harmonic to the tone, and maybe change the phase, depending on the design. I was reading that the phase doesn't change with your loop. Does that describe the complete effect of two inverting stages or is each stage non-inverting?

I have yet to hear somebody (probably my lack of exposure, I was raised in a small town) use a separate preamp and power amp and get the TRUE Marshall tone. I keep hearing people discuss the properties that make up that tone, which includes driving the crap out of the phase inverter, amongst other things. I think that this loop is important because it does exactly what I've been looking for, allow me to create a huge waveform in the preamp and have it leave the chassis, enter another, and hit the phase inverter at the same level as it left the preamp, without changing or adding to the tone. It drives me crazy when people say that something doesn't change the tone and then go on to say that it sounds better. Better is different.

I haven't been around the block that much but I haven't seen anybody do that without affecting tone, even if it is in a good way. I'm really looking forward to trying the loop.

[SDM]

The send buffer inverts the phase, the return stage inverts it again so it ends up the same phase at the end as it started with. So you'd want the preamp buffers to invert, then the loop return will re-invert to the phase it should be.

So if the input into the power amp from the preamp is buffered right and inverted, the plexi preamp should sound like it's a part of the power amp. It'll have it's own power supply though, not part of the power amp's B+ line anymore, so preamp power supply would need to be well thought out to get the voltages, decoupling, and filtering right. Also means the preamp B+ line won't interact with the power amp's B+ line, but I don't think that should really an issue if the preamp is set up right.

As to the 2203 and Rocca preamps, they will not sound quite like the original amps, as they never had 12XXX power amp sections of course. So the 12XXX lower filtering and such will add that flavor to them.

[budubum]

I'd call it the S&M loop...

Or the Subservient Evil Gimp loop.

Or the Loopy-Loop (cause it's crazy how good it doesn't sound)

Hear no evil loop.... you hear none of that evil crap other loops have...

you`re too evil man........ stop it !!!! hahha