SS effects loop schem?

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argonaut
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SS effects loop schem?

Post by argonaut »

I'd like to add a buffered loop to a home brew without adding an additional tube or power supply. I've been rummaging though schems looking for something that I can power off the HT supply and haven't come up with anything worthwhile.

Anyone have a schem they can share or know of an amp I can look to for inspiration?

Thanks!
paulster
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Re: SS effects loop schem?

Post by paulster »

No schem but the solid-state loop Metroamp do is very well regarded and inexpensive.
Badside
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Re: SS effects loop schem?

Post by Badside »

paulster wrote:No schem but the solid-state loop Metroamp do is very well regarded and inexpensive.
I concur!

After looking around for a DIY option, I went with that. It's all nicely packed on a tiny PCB that holds the two jacks. It comes with a variety of decoupling resistors so you can get the proper B+ (it runs on roughly 300V), as well as shielded wires and a switch that takes it out.

I've done the blind test with a few musician friends, none could tell when the loop was in or not.

It uses MOSFETs, which is I believe the only option if you want it to run on high-voltage.

I tried to to reverse-engineer it at first, but I decided that the product was too great and the guy making it deserved his credit (and profit) ;)
But it's a basic MOSFET design. One MOSFET as a buffer, another one as recovery.
Amplifiers built:
Marshall 2204 head with some mods
Low-power 2204 (cathode biased 6V6s)
Single-knob dual-6K6GT amps using a Wattkins uPCB
AC30 clone with Plexified preamp section
AX84 Firefly
argonaut
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Re: SS effects loop schem?

Post by argonaut »

Unfortunately, the metro one won't fit where I would like to put it, and I'm parts rich, money poor at the moment. I really appreciate the suggestions, though. That's the type of loop I had in mind.
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Deric
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Re: SS effects loop schem?

Post by Deric »

I believe the schematic for the Iron Sounds loop is posted at their site.
Deric®
ampdoc1
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Re: SS effects loop schem?

Post by ampdoc1 »

The Klein-Ulator sounds pretty transparent and it looks like a simple circuit to build.

a'doc
paulster
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Re: SS effects loop schem?

Post by paulster »

The Iron Sounds one is, apparently, a straight clone of the one Marshall puts in their 1959 and 2203 reissues (schematics available from www.drtube.com). I haven't verified that the Iron Sounds one is the same personally, though, so take that statement with a large pinch of salt.

The Marshall one isn't a bad sounding loop but it suffers very low headroom as it's op-amp based and typically has to deal with the voltages at the PI input so it's very easy to clip.
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Structo
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Re: SS effects loop schem?

Post by Structo »

What is the amp in question?

I have an Ironsounds FX loop that I would be willing to sell.

It works better for a > 40 watt amp than 50 watts and up.
Tom

Don't let that smoke out!
argonaut
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Re: SS effects loop schem?

Post by argonaut »

I don't care much for the loops that are in the marshall x-amps. They really squish the signal to my ears. At a glance, the ironsound loop does look the same. So I'll stay away from that.

I haven't tried the kleinulator, but have a d-lator that I built. I don't really care for it either as it drastically effects the tone. i was really hoping it wouldn't as I really liked the idea of putting simple passive insert loops in my amps.

l'll probably give the metro loop a try and modify it to fit.

Thanks again for the suggestions.
Badside
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Location: Montreal, Canada

Re: SS effects loop schem?

Post by Badside »

argonaut wrote:l'll probably give the metro loop a try and modify it to fit.

Thanks again for the suggestions.
I seriously can't see a loop being any smaller than the Metro. Its size is basically the 2 Cliff jacks with a small PCB linking the two and extending just a little on each side. It actually goes OVER the preamp tube sockets without any trouble. If you can't fit that, I don't see what you could fit.
Amplifiers built:
Marshall 2204 head with some mods
Low-power 2204 (cathode biased 6V6s)
Single-knob dual-6K6GT amps using a Wattkins uPCB
AC30 clone with Plexified preamp section
AX84 Firefly
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Blindog
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Location: Atlanta

Re: SS effects loop schem?

Post by Blindog »

argonaut wrote:
I haven't tried the kleinulator, but have a d-lator that I built. I don't really care for it either as it drastically effects the tone. i was really hoping it wouldn't as I really liked the idea of putting simple passive insert loops in my amps.
Hey argonaut,

I put insert points in my '68 Traynor YBA-1 that I've converted to Plexi Lead specs. I use my Redplate D-lator with that amp and I totally dig it. Plus I can use the the return control a master volume. Could you describe how you think it's affecting the tone? Just curious.

Mark
"- Yeah, can we have everything louder than everything else? Right!"- Ian Gillan
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