FX & Reverb unit

[tubenit]

I built this for my Tweed Overdrive Special which has a passive effects loop.  The unit plugs into the passive effects loop jacks. 

It adds NO noise level to the TOS.  In fact, it actually makes the amp quieter at idle for some reason with NO loss of touch sensitivity or tone.

The project exceeded my expectations.

The reverb is rich and lush.  Using a digital delay in the FX loop, the FX has a very rich warm huge spacious tone.

I tried a D_mble style LNFB around V1-6 to V1-7 & did not care for it. It gave the amp a compressed tone. The amp has more touch sensitivity in playing without it, IMO.

With respect, Tubenit

[drumslinger2000]

Tubenit,

     excellent little project!!  nice job man.  looking forward to building one after the TOS build.  i'm glad the project didn't take away any of the tone.  what are the tube recommendations for this project?

[tubenit]

For the reverb  typical 12AT7 & half of a 12AX7 for recovery.

For the FX loop, I liked a 12AU7 the very best because I felt it had the clearest tone to it. The 12AT7 and 5751 also sounded pretty good.

Here is the schematic and layout with the local negative feedback in case someone prefers that. I removed it on mine.

With respect, Tubenit

[nateflanigan]

What reverb tank did you use?  Since the hoffman reverb transformer doesn't have any specs listed I don't know how to match it up.

Thanks

[tubenit]

Same reverb trannie and tank like you'd use for a Fender Princeton Reverb.  The ones Hoffman sells.

IF someone wanted to experiment with just an outboard reverb unit without FX then maybe try this one.

With respect, Tubenit

EDIT :   After playing thru this for a couple of months, I decided the reverb needed a tweak.  I paralleled the 12AX7 return. Changed the cathode from 1.5k/22uf to 820R/5uf.  I changed the 180p/220k into grid to 390p/220k.

The result is the reverb sounds bigger and warmer without sounding more intense and hollow and having a "ping" on the high end. It sounds more warmer and more spacious (more like a delay).

[tubenit]

Very quiet no hum or noise added.  Helps with blooming and some sustain. Does add some slight harmonics.

With respect, Tubenit

[MakerDP]

Tagged so I can study this after work. Looks like a nice unit!

[MakerDP]

Hey Tubenit...

You still like this unit?

I'm thinking it would be a good solution for me... just put a passive FX loop in all my builds and use this for reverb and active FX when I use that amp rather than build one or both of those into each amp.

I have all the parts I need for this on-hand so I can basically build it for free, except for the 12AU7, but I can use an AT in there until I get one. Oh, and the socket... but I can rob that from another amp that has an empty one put in there for "future expansion."

[tubenit]

I don't have it anymore.  And I eventually converted it in a SoLow Watt amp with ECL84's & then sold that.

With respect, Tubenit

[andresound]

I built this for my Tweed Overdrive Special which has a passive effects loop.  The unit plugs into the passive effects loop jacks. 

It adds NO noise level to the TOS.  In fact, it actually makes the amp quieter at idle for some reason with NO loss of touch sensitivity or tone.

The project exceeded my expectations.

The reverb is rich and lush.  Using a digital delay in the FX loop, the FX has a very rich warm huge spacious tone.

I tried a D_mble style LNFB around V1-6 to V1-7 & did not care for it. It gave the amp a compressed tone. The amp has more touch sensitivity in playing without it, IMO.

With respect, Tubenit

Hi Tubenit....VERY late to this topic, but came across it while researching for a stand alone tube reverb unit project. Do you by any chance have the schematic and layout in a PDF format?

[sluckey]

I can convert to pdf. Which files do you want converted?

[alathIN]

I can convert to pdf. Which files do you want converted?

I would like to have .pdf versions of the later (post mod) layout and schematic if this offer is still on the table.

[sluckey]

You can do this yourself simply by using any of the free 'print to pdf' utilities available on the net. Windows 10 has this ability built in. Adobe Acrobat Reader also has this feature. Simply open a file and choose print. Now select 'Adobe PDF' or 'Microsoft Print to PDF' as your printer.

[mmaguire9]

Hi
I understand that this is probably a dead topic but I'll give it a shot.
There is a lot of good stuff on the forums but I can't see a lot of it since folks post .sch files.
I run Linux and have no Windows. I can print to pdf with my desktop easily but the file has be opened first.
No application I have can open any of these .sch files.
thank you for the good info in any event.

[Blueboozer]

Hi
I understand that this is probably a dead topic but I'll give it a shot.
There is a lot of good stuff on the forums but I can't see a lot of it since folks post .sch files.
I run Linux and have no Windows. I can print to pdf with my desktop easily but the file has be opened first.
No application I have can open any of these .sch files.
thank you for the good info in any event.

Download the Java version of Jschem and run under Java

Or

Install WINE http://winehq.org. Then install ExpressSCH https://www.expresspcb.com/and run it using WINE.

Just a suggestion.

[Williamblake]

I dont have Linux to do this but i have a Mac and  use Virtual Box to run Windows 7 to run ExpressSCH and am perfectly fine dealing with those files. And thanks for digging out this old thread.

[Jonny Beck]

Can y'all recommend a freeware app for viewing *.sch files?
Thanx in advance

[Willabe]

Can y'all recommend a freeware app for viewing *.sch files?
Thanx in advance

Here ya go;

https://www.expresspcb.com/pcb-cad-software/