Problems with LND150 FX Loop

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OdgeUK
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Problems with LND150 FX Loop

Post by OdgeUK » Fri Feb 09, 2018 10:06 am

Hi All

I had a local, and very well-respected, tech install the Tube-Town Active, serial FX-Loop LND150 in my '79 2203.

https://www.tube-town.net/ttstore/Kits/ ... :5973.html

Image

When I picked it up, he said he thought the way the loop was supposed to be installed was very unusual, between Tonestack and Master Volume, and that he had set the levels on the trims as best he could. Too high and it increased the gain too much, and too low and the amp sounded castrated.

So I finally tried it out last night with nothing in the loop, all good, as I remember the amp. So I tried the loop and had three problems immediately:

- My TC Flashback delay clipped the amp on low notes when engaged (but no problems with the pedal switched off). Boss Chorus was fine.
- The overall volume level of the amp actually dropped slightly when engaging any pedals in the loop, and the tone noticibly darkened
- An MXR Microamp on FULL, in the loop, made no volume increase whatsoever. Just a bit more gain.

Image

I'm going to fiddle with the Send and Return levels on the FX board later. I called my tech and he said I can bring it in for another look, but he noted that he didn't think i'd like the way it operates and that he'd spent some time getting the Send and Receive levels at a level where the tone was impacted least and still maintained unity volume when the FX loop was jumpered with a Patch cable.
Last edited by OdgeUK on Thu Feb 22, 2018 12:14 pm, edited 1 time in total.
73 JMP 1987 w/LarMar
78 JMP 1987
79 2104
Peavey JSX 120
Marshall 1936 G12-65
Gibson LP Custom, Squier CV 50's Strat w/SD '59

alexradium
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Re: Problems with LND150 FX Loop

Post by alexradium » Tue Feb 20, 2018 8:07 am

edit
Last edited by alexradium on Fri Dec 20, 2019 1:50 pm, edited 1 time in total.

OdgeUK
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Re: Problems with LND150 FX Loop

Post by OdgeUK » Thu Feb 22, 2018 12:08 pm

alexradium wrote:
Tue Feb 20, 2018 8:07 am
That design has serious flaws, sorry for you, not only you get the picture playing through it but also simply looking at the schematic, too bad asking money for bad working appliances.
Really? I was told that the loop was very similar to the MetroAmp Zero-Loss FX loop? I chose it because it's expensive to buy and ship the Metroamp version from US to UK, whereas the TubeTown FX Loop is in Germany.

I have posted this as an issue on the Tube Town forum and the owner only wants to help if I can provide a schematic. I'm not sure why this is required as the board schematic is already known and the wiring is very simple (one wire to B+, one to Earth and then a pair of wires to separate the Tone Stack from the Master Volume.

Do you recommend any other alternatives for a JMP?
73 JMP 1987 w/LarMar
78 JMP 1987
79 2104
Peavey JSX 120
Marshall 1936 G12-65
Gibson LP Custom, Squier CV 50's Strat w/SD '59

alexradium
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Joined: Thu Oct 06, 2011 9:03 am
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Re: Problems with LND150 FX Loop

Post by alexradium » Fri Feb 23, 2018 8:32 am

edit
Last edited by alexradium on Fri Dec 20, 2019 1:50 pm, edited 1 time in total.

OdgeUK
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Re: Problems with LND150 FX Loop

Post by OdgeUK » Fri Feb 23, 2018 5:29 pm

alexradium wrote:
Fri Feb 23, 2018 8:32 am
This loop is not similar to the metro one, but it needs to be modified in order to work similar way.
If you want a commercial alternative to metro I can give you a link in private, don't want to mess with forum owner.
Yes please Alex, I'd be interested in that.
73 JMP 1987 w/LarMar
78 JMP 1987
79 2104
Peavey JSX 120
Marshall 1936 G12-65
Gibson LP Custom, Squier CV 50's Strat w/SD '59

Bbsmith26
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Re: Problems with LND150 FX Loop

Post by Bbsmith26 » Fri Dec 14, 2018 5:02 pm

alexradium wrote:
Fri Feb 23, 2018 8:32 am
This loop is not similar to the metro one, but it needs to be modified in order to work similar way.
If you want a commercial alternative to metro I can give you a link in private, don't want to mess with forum owner.
Hi, I also have bought/installed the tube town LND150 loop. Is there any chance you might be able to send me the mods you mention to make it function more like the metro loop, and the name of the alternative loop you mention?
Last edited by Bbsmith26 on Thu Dec 20, 2018 6:00 am, edited 1 time in total.

OdgeUK
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Re: Problems with LND150 FX Loop

Post by OdgeUK » Mon Dec 17, 2018 4:33 pm

How have you found the Tube Town loop? Unusable for me. It's either been installed badly, or it's a heap of crap. I've got a Metroloop in the box waiting to replace it once I get time.
73 JMP 1987 w/LarMar
78 JMP 1987
79 2104
Peavey JSX 120
Marshall 1936 G12-65
Gibson LP Custom, Squier CV 50's Strat w/SD '59

Bbsmith26
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Posts: 2
Joined: Fri Dec 14, 2018 4:01 pm
Just the numbers in order: 13492

Re: Problems with LND150 FX Loop

Post by Bbsmith26 » Tue Dec 18, 2018 6:30 am

OdgeUK wrote:
Mon Dec 17, 2018 4:33 pm
How have you found the Tube Town loop? Unusable for me. It's either been installed badly, or it's a heap of crap. I've got a Metroloop in the box waiting to replace it once I get time.
I've actually found it to be transparent, but I had to remove the 500pf Silva mica cap. I believe it's a bright cap, so as the send volume is decreased it retains the highs. As soon as I removed it worked as I expected. I believe the current manual online say it is optional also.

It's placed between the tonestack and master volume in a 2204 style build. Running it on 350v. Send level is a bit less than halfway and return is set to a bit over halfway.

I have been trying it with a dpdt to take it in and out the circuit and can't tell a difference. I've been debating whether it reduces the low end ever so slightly but I can't tell if it's just in my head or not.

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