Mojo has a new loop

[232cap]

http://www.mojotone.com/amp-parts/Mojot ... Amplifiers

 

[Ventura]

I thought you were talking about me...

 

[dawnofdreamx97]

http://www.mojotone.com/amp-parts/Mojotone-Discrete-Hi-Voltage-Series-Effects-Loop-for-Vacuum-Tube-Amplifiers

ive had one a while ago , sounded pretty good.

 

[tonmazz]

Art, Any idea how this compares to the Metro loop? Can't see anything being as good as that but if this is , the price is right for sure.

 

[mboogman]

I've got one. I'm still working it out with one of their techs, for my '79 JMP. It works, is an easy install, I'm just trying to get the levels and Frequency response to be just right.

 

[mboogman]

I've got one. I'm still working it out with one of their techs, for my '79 JMP. It works, is an easy install, I'm just trying to get the levels and Frequency response to be just right.

Meaning it sucks tone?

The reason I ask, is I have used 2 of them and had to mod them to get them to sound correct.

On the return side they are running the signal through a 1 meg resistor then a 10K prior to the transistor. Since the loop is -10dB (pedal level) output, the signal fed into the return is very low and the 1 meg resistor is way to high for this purpose. The return side is supposed to bring the signal back up, so there is no reason to attenuate an attenuated signal.

If you look at the board, the 1 meg resistor is soldered where the silkscreen indicates a .022uF cap. If you remove the 1 meg resistor and replace it with a .022uF cap then the loop works correctly. I am curious if these were incorrectly wired with the 1Meg input resistor because the loop works correctly mostly transparent with the cap as indicated by the silkscreen.

Hmm. I'll look and see what's going on with mine, because yeah, I'm seeing a significant drop in HF.

 

[232cap]

I never installed a mojo loop I just caught it on their web site, it is really hard to beat the Metro loop from my experience and I installed a bunch.

 

[jerrydyer]

the metro loop is cool. a little white noise but...???? they all have drawbacks. Larrys from Larry Amplification has been the purist, quietest one ive used and installed for people. Ive been happy with Mojo stuff in the past but havent tried this loop. prob the same as the metro or generic marshall loop. I can get away with effects in a passive loop for low level recording. sounds the best to me too.

 

[LP Freak]

I'd stick with the Metro. I'm yet to hear a better loop.

 

[MrDan666]

Yep that is what happen when I used them too. Changed out the 1meg resistor with the cap and all was good.

Good to know, thanks for sharing the info! I have one of those Mojo Loops coming to me soon, so i will keep that in mind and make the adjustments.

 

[232cap]

I've got one. I'm still working it out with one of their techs, for my '79 JMP. It works, is an easy install, I'm just trying to get the levels and Frequency response to be just right.

Meaning it sucks tone?

The reason I ask, is I have used 2 of them and had to mod them to get them to sound correct.

On the return side they are running the signal through a 1 meg resistor then a 10K prior to the transistor. Since the loop is -10dB (pedal level) output, the signal fed into the return is very low and the 1 meg resistor is way to high for this purpose. The return side is supposed to bring the signal back up, so there is no reason to attenuate an attenuated signal.

If you look at the board, the 1 meg resistor is soldered where the silkscreen indicates a .022uF cap. If you remove the 1 meg resistor and replace it with a .022uF cap then the loop works correctly. I am curious if these were incorrectly wired with the 1Meg input resistor because the loop works correctly mostly transparent with the cap as indicated by the silkscreen.

I can see a wrong value resistor installed but a resisitor in place of a cap, now that's some quality control.

 

[mboogman]

I've got one. I'm still working it out with one of their techs, for my '79 JMP. It works, is an easy install, I'm just trying to get the levels and Frequency response to be just right.

Meaning it sucks tone?

The reason I ask, is I have used 2 of them and had to mod them to get them to sound correct.

On the return side they are running the signal through a 1 meg resistor then a 10K prior to the transistor. Since the loop is -10dB (pedal level) output, the signal fed into the return is very low and the 1 meg resistor is way to high for this purpose. The return side is supposed to bring the signal back up, so there is no reason to attenuate an attenuated signal.

If you look at the board, the 1 meg resistor is soldered where the silkscreen indicates a .022uF cap. If you remove the 1 meg resistor and replace it with a .022uF cap then the loop works correctly. I am curious if these were incorrectly wired with the 1Meg input resistor because the loop works correctly mostly transparent with the cap as indicated by the silkscreen.

Hmm. I'll look and see what's going on with mine, because yeah, I'm seeing a significant drop in HF.

Yep that is what happen when I used them too. Changed out the 1meg resistor with the cap and all was good.

Just finished this swap. You are absolutely right. All is good! Thanks a bunch.

 

[lolzgreg]

And Dave of Baron Custom amps trumps the electronics world again.... what else is new

You always pop in to these kind of threads and provide killer info Dave

 

[dawnofdreamx97]

the metro loop is cool. a little white noise but...???? they all have drawbacks. Larrys from Larry Amplification has been the purist, quietest one ive used and installed for people. Ive been happy with Mojo stuff in the past but havent tried this loop. prob the same as the metro or generic marshall loop. I can get away with effects in a passive loop for low level recording. sounds the best to me too.

i think the marshall one uses an opamp like a TL072 .... suckage

 

[rpurdue]

Hey guys. I just got this loop as well and it sounds off. Can anyone tell me which resistor is wrong? I can't find a schematic and all the resistors are too close to the board to see the printed number under neath?

Thanks

 

[moltenmetalburn]

Looks like a copy of the metro high voltage MOSFET loop.

 

[mboogman]

Hey guys. I just got this loop as well and it sounds off. Can anyone tell me which resistor is wrong? I can't find a schematic and all the resistors are too close to the board to see the printed number under neath?

Thanks

It would be Sunday before I can get any kind of picture of this, but looking at the board, with the connectors facing away from you, it's below the return connector. It probably looks like the slot for the resistor is too long, and come to find out, when I pulled it off, it had ".022" (I think) silk screened onto the board. Hope that helps.

 

[mboogman]

Hey guys. I just got this loop as well and it sounds off. Can anyone tell me which resistor is wrong? I can't find a schematic and all the resistors are too close to the board to see the printed number under neath?

Thanks

It would be Sunday before I can get any kind of picture of this, but looking at the board, with the connectors facing away from you, it's below the return connector. It probably looks like the slot for the resistor is too long, and come to find out, when I pulled it off, it had ".022" (I think) silk screened onto the board. Hope that helps.

Yep that is correct. For some reason they have a 1 meg resistor in place of the .022uF cap. Pull the 1 meg resistor and put in a .022uF cap and you will be good to go.

On mine, I think it was actually a 470k? I don't remember exactly, but once I swapped it for the cap, it was right on. I think I'm actually going to put in a pot too, to control the return trim, kind of like an active loop master.

 

[FortinAmps]

Hey guys. I just got this loop as well and it sounds off. Can anyone tell me which resistor is wrong? I can't find a schematic and all the resistors are too close to the board to see the printed number under neath?

Thanks

It would be Sunday before I can get any kind of picture of this, but looking at the board, with the connectors facing away from you, it's below the return connector. It probably looks like the slot for the resistor is too long, and come to find out, when I pulled it off, it had ".022" (I think) silk screened onto the board. Hope that helps.

Yep that is correct. For some reason they have a 1 meg resistor in place of the .022uF cap. Pull the 1 meg resistor and put in a .022uF cap and you will be good to go.

Yeah man, same problem with the one I have. Mine had a 470k stuffed in there.

 

[rpurdue]

Thanks Guys. Mboogman, if you can get a pic sunday it would be much appreciated!