Parallel effects loop for Marshall style amps
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- jerrydyer
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Hey Larry. My send level is more like a blend. hhhhmmmm. its a great loop thought. What pro 's and con's of only using a 2.2k on the receiving end instead of the 1.5k and a 22uf? thanx
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Jerrydyer
You mean there is no volume boost when you turn up the send level?
And what do you think about the levels of the amp when you don't use the loop? I think mine 2204 is extremly loud with the master on 2....
Larry, when the loop is not in use the signal is not amplified is it??
Regards Marcel
You mean there is no volume boost when you turn up the send level?
And what do you think about the levels of the amp when you don't use the loop? I think mine 2204 is extremly loud with the master on 2....
Larry, when the loop is not in use the signal is not amplified is it??
Regards Marcel
- novosibir
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Be more concrete! What happens, when...jerrydyer wrote:Hey Larry. My send level is more like a blend.
The amplification factor of the recovery stage is going from 59.0 down to 24.3 - or in other terms from 35.4dB down to 27.7dBjerrydyer wrote:What pro 's and con's of only using a 2.2k on the receiving end instead of the 1.5k and a 22uf?
Larry
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- novosibir
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The dry path of the loop has an attenuation of -33.0dB with the Return Level on zero or dimed and an attenuation of -32.5dB with the Return Level on about 6...7, when nothing is plugged in.thinlizzy wrote:Larry, when the loop is not in use the signal is not amplified is it??
The recovery stage has an amplification of +35.4dB, that means, that the signal with the loop will be slightly amplified by about +3dB - theoretical.
That's based on average tube datas, but when you have a pretty strong tube for the loop, then it might be a tad more, kinda +5dB...+6dB.
In this case you can fine tweak the attenuation by swapping the 68K with a 56K, a 47K or even a 39K for more attenuation, to get to exactly that point, where it would be w/o the loop section.
Larry
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- novosibir
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Any A/B-box used as a on/off switch works fine w/o pop.
Larry
Larry
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- antosimoni
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as I'm tryin' to have the least influence of the loop on the head sound can I use a switch to make the entire loop switchable on/off?? if yes how I've to do it??novosibir wrote:The dry path of the loop has an attenuation of -33.0dB with the Return Level on zero or dimed and an attenuation of -32.5dB with the Return Level on about 6...7, when nothing is plugged in.thinlizzy wrote:Larry, when the loop is not in use the signal is not amplified is it??
The recovery stage has an amplification of +35.4dB, that means, that the signal with the loop will be slightly amplified by about +3dB - theoretical.
That's based on average tube datas, but when you have a pretty strong tube for the loop, then it might be a tad more, kinda +5dB...+6dB.
In this case you can fine tweak the attenuation by swapping the 68K with a 56K, a 47K or even a 39K for more attenuation, to get to exactly that point, where it would be w/o the loop section.
Larry
thanks for your help
in loudspeakers we trust
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So if you place the loop after the master volume, it is still a good mod to place a 100k at the wiper of the master volume?novosibir wrote:In principle, no!thinlizzy wrote:Is there a reason why I can't place it between the treble wiper and the master volume?
But I'll tell you (all) now the pros and cons:
When a Mastervolume control is placed directly before the PI stage and set to a low setting, the sound becomes pretty thin - therefore it's always a good mod, to place a 100K resistor between the wiper and the 22n PI's input cap, to avoid this phenomenon as much as possible. A higher value than 100K will cost you some highs and gain, because you create a voltage divider with the input impedance of the PI stage!
When you go from the loop's Return recovery stage directly into the PI, the upper phenomenon doesn't occur.
Larry
Marcel
- jerrydyer
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when i have something in the loop, my send level acts more like a blend not boost. I happen to like it but I figure I have something wired incorrectly. It actually gets a little louder towards dry (counterclockwise) also i am using a 1meg instead of a 250k so. With the master still in place my sound was mushy. I removed the master and now I have a more traditional sound (non master tone) I like the loop a lot. Also my recovery cathode is just a 2.2k (no 22ufcap ) Still teaking.
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- novosibir
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Seems, that you haven't read my concerning post correctly?jerrydyer wrote:when i have something in the loop, my send level acts more like a blend not boost.
When you want to use the loop as a booster, then you have to loop in just a cable, not an effects device. The looped in cable of course should have an on/off switch, to that you can switch the booster on and off
Once again - either effects loop, or booster. Both at the same time isn't possible, except you build two of this loop in series into the amp.
Larry
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- jerrydyer
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that was thinlizzy. I was just making the statement that my send level acts more like a blend level. Clockwise more effects but no raise in volume. Counterclockwise more dry and a little louder. Works great for me. I just asked about a 2.2k instead of the 1.5k and 22uf. No problems really just playing around.
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- novosibir
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Email with a schem w/ true bypass switch, but w/o LED already sent!thinlizzy wrote:Has some one a schematic for al simple on/off switch with a led that does'nt make a pop sound while switching.
Larry
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- novosibir
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antosimoni wrote:as I'm tryin' to have the least influence of the loop on the head sound can I use a switch to make the entire loop switchable on/off?? if yes how I've to do it??
Email with a schem w/ true bypass switch already sent!joshwilson3 wrote:Do you guys have a recommendation for an on/off switch?
Larry
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????? what was I?? I read all Larry's mail very carefully....jerrydyer wrote:that was thinlizzy. I was just making the statement that my send level acts more like a blend level. Clockwise more effects but no raise in volume. Counterclockwise more dry and a little louder. Works great for me. I just asked about a 2.2k instead of the 1.5k and 22uf. No problems really just playing around.