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Hoffman Amps Forum image Author Topic: tube effects loop schematic  (Read 18136 times)

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Offline Tone Junkie

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tube effects loop schematic
« on: March 27, 2020, 01:57:43 am »

Question For Tubenit . Been away for a while glad to be back. Ive  had a D,mars overdrive on my bench to finish for a friend for way to long. Looking for the effects loop schematic . That you guys have been using on the TOS and the Dumble related versions. Looking for the discussion were your using resister instead of pot. on the send.I thought I had saved every relevent conversation. But of course I cant find it.
Thanks Bill

Offline Latole

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Re: tube effects loop schematic
« Reply #1 on: March 27, 2020, 03:42:10 am »
« Last Edit: March 27, 2020, 03:45:11 am by Latole »

Offline tubenit

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Re: tube effects loop schematic
« Reply #2 on: March 27, 2020, 04:41:16 am »
I have always used a pot on send.  I have used a 33k resistor on one amp and a 82k resistor on "return" on two amps.

I've seen where some guys use a 22k on send but I don't remember ever doing that?

With respect, Tubenit

Offline Latole

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Re: tube effects loop schematic
« Reply #3 on: March 27, 2020, 04:53:48 am »
Better control with pots.

Offline Tone Junkie

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Re: tube effects loop schematic
« Reply #4 on: March 27, 2020, 05:10:20 pm »

Thank You Lotole I have that schematic. I would use all pots but don't have space and I already have a faceplate with set number of holes for effects loop . Its been sitting on my bench for so long that I lost my notes . Been away from building amps for more than a year . Boeing sent us home for two weeks,so now I have time to finish this amp for my friend .
Thank You tubenit that answered my question. We had also had discussion. on parallel and series on this effects loop.
 I have been building pedals ,guitars and working to much and trying to keep my chops up on the guitar has just been taking all my time. Glad to work on an amp for a change. Thanks Bill

Offline Tone Junkie

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Re: tube effects loop schematic
« Reply #5 on: March 27, 2020, 05:14:27 pm »

Thank You Lotole that might be it .have to get out and do some work . will read thru later.
Thanks Bill

Offline Latole

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Re: tube effects loop schematic
« Reply #6 on: March 28, 2020, 03:31:00 am »
I discovered tubebit and I appreciate its information as well as this excellent schematic.
I wish you would return to work at Boeing very soon, but I'm afraid it won't be until May, and more importantly, everyone stays healthy.

Offline Tone Junkie

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Re: tube effects loop schematic
« Reply #7 on: March 28, 2020, 08:24:39 pm »
Latole I will be honest I love building planes but Boeing recently, or in the past 5 yrs has become a shitty place to work . They don't care anything about there employees. They would work us 10,s 7 days a week if they could. the only reason they closed the plant is so many people were getting sick . It became a PR headache for them so they sent us home for 2 weeks. I will say this to there credit. It was paid.

Offline Tone Junkie

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Re: tube effects loop schematic
« Reply #8 on: March 28, 2020, 09:07:31 pm »

There's another schematic I would like to find they made this loop into a parellel loop by adding a pot. for a mix pot.


Offline Latole

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Re: tube effects loop schematic
« Reply #9 on: March 29, 2020, 03:25:19 am »
Mesa Boogie Blue Angel and DC-3 ;

« Last Edit: March 29, 2020, 03:27:40 am by Latole »

Offline Latole

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Re: tube effects loop schematic
« Reply #10 on: March 29, 2020, 03:30:20 am »
Latole I will be honest I love building planes but Boeing recently, or in the past 5 yrs has become a shitty place to work . They don't care anything about there employees. They would work us 10,s 7 days a week if they could. the only reason they closed the plant is so many people were getting sick . It became a PR headache for them so they sent us home for 2 weeks. I will say this to there credit. It was paid.

Sorry for you. I wonder how will be the future after covid 19 for all of us ?

Offline kagliostro

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Re: tube effects loop schematic
« Reply #11 on: March 29, 2020, 05:10:48 am »
Quote
There's another schematic I would like to find they made this loop into a parellel loop by adding a pot. for a mix pot.





The pot is a dual ganged pot used with reversed connection on each section

Franco
« Last Edit: March 29, 2020, 05:12:50 am by kagliostro »
The world is a nice place if there is health and there are friends

Offline tubenit

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Re: tube effects loop schematic
« Reply #12 on: March 29, 2020, 07:19:13 am »
There are quite a few schematics shown in the active FX loop in ARCHIVES:

http://el34world.com/Forum/index.php?topic=10208.0

Offline bruce_w

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Re: tube effects loop schematic
« Reply #13 on: March 29, 2020, 02:22:42 pm »
Latole I will be honest I love building planes but Boeing recently, or in the past 5 yrs has become a shitty place to work . They don't care anything about there employees. They would work us 10,s 7 days a week if they could. the only reason they closed the plant is so many people were getting sick . It became a PR headache for them so they sent us home for 2 weeks. I will say this to there credit. It was paid.

Sorry for you. I wonder how will be the future after covid 19 for all of us ?

Mandatory face masks, plexiglass booths in all restaurants and stores. You will have to register/license all gatherings with the government . Quarantine shelters for anyone suspected of being sick. Just like 911 all this is here to stay.

Offline sluckey

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Re: tube effects loop schematic
« Reply #14 on: March 29, 2020, 02:31:27 pm »
That's a very bleak outlook. I have faith that a vaccine will be developed. Hopefully in time for us old farts.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Tone Junkie

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Re: tube effects loop schematic
« Reply #15 on: March 29, 2020, 06:16:52 pm »

Thank you all for the schematics I did have the one from Merlins book. I have his books. I new somewhere there was a stach of schematics on the tube effects loop we had been using in the past . I like the one Tubnit and others had used . Ive had good success and also in some builds had used recovery pot.as master volume. when doing that I found I needed a bypass switch for the effects loop to dial my volumes properly . I have different loops I use for high gain amps. I agree with sluckey I don't have bleak outlook on this by years end it will be back to normal and this will just be a problem we had to overcome.
Thanks Bill

Offline Tone Junkie

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Re: tube effects loop schematic
« Reply #16 on: March 29, 2020, 06:30:31 pm »

Thank guys it was the one were they added the mesa twist to this loop. the 25k pot. That I used before. I printed. and put it in my folder for safe keeping.
Thanks Bill

Offline Tone Junkie

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Re: tube effects loop schematic
« Reply #17 on: May 04, 2020, 12:59:33 am »
bump

Offline taiwanluthiers

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Re: tube effects loop schematic
« Reply #18 on: March 13, 2025, 10:58:05 am »
Latole I will be honest I love building planes but Boeing recently, or in the past 5 yrs has become a shitty place to work . They don't care anything about there employees. They would work us 10,s 7 days a week if they could. the only reason they closed the plant is so many people were getting sick . It became a PR headache for them so they sent us home for 2 weeks. I will say this to there credit. It was paid.

Sorry saw this in a google search trying to find out about adding effect loops to a AB763.

Explains why Boeing planes seems to have self-opening doors...

Offline Latole

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Re: tube effects loop schematic
« Reply #19 on: March 13, 2025, 12:10:22 pm »
Latole I will be honest I love building planes but Boeing recently, or in the past 5 yrs has become a shitty place to work . They don't care anything about there employees. They would work us 10,s 7 days a week if they could. the only reason they closed the plant is so many people were getting sick . It became a PR headache for them so they sent us home for 2 weeks. I will say this to there credit. It was paid.

Sorry saw this in a google search trying to find out about adding effect loops to a AB763.

Explains why Boeing planes seems to have self-opening doors...

Effects loop ;

https://el34world.com/Forum/index.php?topic=26300.new;topicseen#new

 


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