It is currently Mon Mar 16, 2020 7:59 am

All times are UTC - 7 hours



Post new topic Reply to topic  [ 14 posts ] 
Author Message
Post subject: Wished for effect return jack - here it is - the mod!
Posted: Sat Nov 23, 2013 11:37 am
Offline
Hobbyist
Hobbyist

Joined: Sat Nov 23, 2013 9:16 am
Posts: 16
Direct access to power tube amp through effect return.
Let you use line out and put pedals in between as well

Normal -10dB line level.

Disclaimer: Certainly voids your warranty - if any left.
Remove power cord and let it be for some hours before open amp
And when drilling 11mm hole for jack - be sure to vacuum any remnance inside out

But simple to do:
Components needed:
TRS jack with breaking contacts
15kohm 1/8W resistor
0.1uF polyester capacitor
20cm unshielded wire

Image

Updated link that shows modification
Image link


Enjoy.


Last edited by larioso on Fri Jan 24, 2020 5:54 am, edited 2 times in total.

Top
Profile
Fender Play Winter Sale 2020
Post subject: Re: Wished for effect return jack - here it is - the mod!
Posted: Tue Nov 26, 2013 7:04 am
Offline
Hobbyist
Hobbyist

Joined: Fri May 03, 2013 6:44 am
Posts: 14
Thanks alot for the this. But for those of us who are OK with solder but have no idea how to read a schematic would you let us know by color etc where everything goes?
I see the following:
Orange from jack to the end of R17
Yellow from jack to the lifted post of R26?
Cap from jack to ?
Resistor to and from?
Blue wire from jack to ?

Tim S


Top
Profile
Post subject: Re: Wished for effect return jack - here it is - the mod!
Posted: Tue Nov 26, 2013 7:42 am
Offline
Hobbyist
Hobbyist

Joined: Sat Nov 23, 2013 9:16 am
Posts: 16
Sure, I try to fill in the blanks.

The jack I got have the breaking side to the right in image - as mounted.
That would be the side having no connection when plug is in place - jack used.
This is the column of three blobdots on the left in schematics.

The three blobdots on the left in schematic - marked with red text - are on the right in image.
So jack is upside down, you could say, compared to schematics.

What you wrote is correct, I found earth/ground at the end of R17 - orange wire.
Blue wire goes to the cut legpart of R26 - the legpart that is left on board.
Lifted part or R26 is yellow wire.
Solder 0.1uF capacitor at top left connector in image, other side of that to 15kohm resistor and resistor to blue wire, and to legpart on board(former end of R26).


Top
Profile
Post subject: Re: Wished for effect return jack - here it is - the mod!
Posted: Tue Nov 26, 2013 6:18 pm
Offline
Hobbyist
Hobbyist

Joined: Fri May 03, 2013 6:44 am
Posts: 14
Got it (I think!)
The blue wire is attached to the tip of the jack as well
as the center lug next to it. The other end is soldered
to the cut leg of R26 that is left in the board, along with
one end of the 15 ohm resistor.
The other end of the 15 ohm resistor is soldered to one
end of the 0.1uf cap, the other end of the cap is soldered
to the jack tip.
The yellow wire is soldered to the (now) free end of R26.
The orange is the ground/earth.

I'm surprised Fender didn't do this as it seems to be a very
easy and inexpensive thing at the manufacturing level.
Maybe it would divert sales from other amps in their line-up?

Thanks again.
Tim S


Top
Profile
Post subject: Re: Wished for effect return jack - here it is - the mod!
Posted: Wed Nov 27, 2013 3:04 am
Offline
Hobbyist
Hobbyist

Joined: Sat Nov 23, 2013 9:16 am
Posts: 16
That sound right.

Just beware that the jack you get might have the breaking side opposite of this one I got.

So look at schematics, the right side have this lifted jumper symbol(marked tip), there is where tip of plug will connect.

When plug is removed is will make contact with terminal on the left.

My image mirrored left will correspond to schematics - all terminal have the same position.
Another brand may have the breaking side opposite - so with terminals up, it correspond to schematics without mirroring.

Hope I don't cause confusion.

I agree it would be simple thing to do this from start - but you always have to decide when to draw the line when manufacturing stuff.

Another thing, since it to some extent aim for recording having usb cabinet sim - an internal 25W resistor connected when no speaker cable is inserted would be good. These low wattage models could have that. Then you cover the home recording situation that many have today and don't bother neighbours.

But you could just buy a 25W 8 ohm resistor and solder on a mono plug - and that is covered as well. Plug in to speaker jack - and you have a load and won't damage amp.

Laney Ironheart Studio is a very clever builld for recording purposes.

I experiment a lot with sound - and wanted a fender style power amp to combine with other preamps so I got the X2 and made this modd. You have to double price to get a fender with effect return.


Top
Profile
Post subject: Re: Wished for effect return jack - here it is - the mod!
Posted: Wed Nov 27, 2013 7:42 am
Offline
Hobbyist
Hobbyist

Joined: Fri May 03, 2013 6:44 am
Posts: 14
Sorry about this individual teacher/student thing!
I found a TRS stereo switching jack. But I'm not
sure if the stereo part is a deal breaker.
In all other respects it looks identical to yours.
I assume the ground contact (on the left side on
your plug) is the key to finding out which side of
the plug is which?

Tim S


Top
Profile
Post subject: Re: Wished for effect return jack - here it is - the mod!
Posted: Wed Nov 27, 2013 9:28 am
Offline
Hobbyist
Hobbyist

Joined: Sat Nov 23, 2013 9:16 am
Posts: 16
I think it's easy to see which side is still connected. The breaking side is a little bent at the end and will be lifted when plug is inserted.

I digital multimeter with ohm measurement is a good investment I think.

Or connect headphone and test with a battery or something - just quickly touching would make a noise. Or apply music from a device you got or something.

Just wanted to make aware that different brands of jacks might have the breaking side opposite.


Top
Profile
Post subject: Re: Wished for effect return jack - here it is - the mod!
Posted: Wed Nov 27, 2013 9:42 am
Offline
Hobbyist
Hobbyist

Joined: Fri May 03, 2013 6:44 am
Posts: 14
Thanks I'm goin' in, or at least I will when the parts arrive!

Tim S


Top
Profile
Post subject: Re: Wished for effect return jack - here it is - the mod!
Posted: Sun Dec 01, 2013 5:03 pm
Offline
Hobbyist
Hobbyist
User avatar

Joined: Thu Nov 15, 2012 1:22 pm
Posts: 69
Great ideea to post it here. Thanx for that! As soon as my warantee will pass, have to try this. (Found something similar for Micro Terror, but not for SCX2, untill now)


Top
Profile
Post subject: Re: Wished for effect return jack - here it is - the mod!
Posted: Sun Feb 01, 2015 7:56 am
Offline
Hobbyist
Hobbyist

Joined: Sun Feb 01, 2015 7:34 am
Posts: 3
Thanks a lot for the info, I’m not an expert and I have some doubts and maybe someone can help me.

Asuming that you are using an stereo TRS jack with switching contacts, When you insert a mono plug, the ring and sleeve get connected together, so In your scheme the yellow cable gets connected with ground, I’m right? That’s not dangerous?. The sleeve is intended to be connected with ground?

The 15kohm 1/8W resistor and the 0.1uF polyester capacitor are strictly necessary? I saw other mods for superchamp xd that doesn’t use it.

With this mod you get direct access to power tubes or to 12AX7 and then power tubes?

Someone have considered adding an independent effect loop out?


Top
Profile
Post subject: Re: Wished for effect return jack - here it is - the mod!
Posted: Sun Feb 01, 2015 12:25 pm
Offline
Hobbyist
Hobbyist

Joined: Sat Nov 23, 2013 9:16 am
Posts: 16
jmp1prs wrote:
Thanks a lot for the info, I’m not an expert and I have some doubts and maybe someone can help me.

Asuming that you are using an stereo TRS jack with switching contacts, When you insert a mono plug, the ring and sleeve get connected together, so In your scheme the yellow cable gets connected with ground, I’m right? That’s not dangerous?. The sleeve is intended to be connected with ground?

The 15kohm 1/8W resistor and the 0.1uF polyester capacitor are strictly necessary? I saw other mods for superchamp xd that doesn’t use it.

With this mod you get direct access to power tubes or to 12AX7 and then power tubes?

Someone have considered adding an independent effect loop out?


Hi
It's designed to use a mono plug and short to ground.
Extra resistor+cap is to give about same load in line out circuits when doing that.

You can use line out as effect send and plug return from effect into this jack in this design.
From schematics you can see that plug into line input as of this design it breaks internal connection from preamp to poweramp making line out free for a serial loop effect if you want.

You can use amp as original, or connect something into power amp from another preamp of some sort, or as an effect loop using preamp+effect+power amp in.

Signal enter before 12AX7 that is just about 3 times gain, and other part in 12AX7 is phase inverter for power tubes. Normal line out is just solid state stuff all of it.


Top
Profile
Post subject: Re: Wished for effect return jack - here it is - the mod!
Posted: Fri Feb 06, 2015 7:18 pm
Offline
Hobbyist
Hobbyist

Joined: Sun Feb 01, 2015 7:34 am
Posts: 3
larioso wrote:
jmp1prs wrote:
Thanks a lot for the info, I’m not an expert and I have some doubts and maybe someone can help me.

Asuming that you are using an stereo TRS jack with switching contacts, When you insert a mono plug, the ring and sleeve get connected together, so In your scheme the yellow cable gets connected with ground, I’m right? That’s not dangerous?. The sleeve is intended to be connected with ground?

The 15kohm 1/8W resistor and the 0.1uF polyester capacitor are strictly necessary? I saw other mods for superchamp xd that doesn’t use it.

With this mod you get direct access to power tubes or to 12AX7 and then power tubes?

Someone have considered adding an independent effect loop out?


Hi
It's designed to use a mono plug and short to ground.
Extra resistor+cap is to give about same load in line out circuits when doing that.

You can use line out as effect send and plug return from effect into this jack in this design.
From schematics you can see that plug into line input as of this design it breaks internal connection from preamp to poweramp making line out free for a serial loop effect if you want.

You can use amp as original, or connect something into power amp from another preamp of some sort, or as an effect loop using preamp+effect+power amp in.

Signal enter before 12AX7 that is just about 3 times gain, and other part in 12AX7 is phase inverter for power tubes. Normal line out is just solid state stuff all of it.


Hi Larioso, thanks a lot for your response!

Can you please check if this alternative based on your schematic adding line in and line out could work?

Image

In this case if you use the dedicated line out/send for the effect loop, the resistance and the capacitor is included, but if you use another external preamp not, that would be ok?
If you plug in the line out/send and the line in/return is empty there wont be any load on the 12ax7, this could be dangerours? In your scheme this never happens.

Best Regards


Top
Profile
Post subject: Re: Wished for effect return jack - here it is - the mod!
Posted: Sun Feb 22, 2015 2:53 pm
Offline
Aspiring Musician
Aspiring Musician

Joined: Sun Jul 01, 2007 12:20 pm
Posts: 496
You lost me at "drill".

Over my head! Maybe Fender will include it in the next version.


Top
Profile
Post subject: Re: Wished for effect return jack - here it is - the mod!
Posted: Tue Dec 20, 2016 7:43 pm
Offline
Hobbyist
Hobbyist

Joined: Sat Nov 23, 2013 9:16 am
Posts: 16
jmp1prs wrote:
In your scheme this never happens.

Best Regards


No, I never bothered with line out jack at all, I picked the signal where it does not matter if something is plugged into line out or not for the line input to work as default of as effect return, or power amp input.

I eventually just left out the orange ground wire as well. Thought at first that it would be good with some load on 15k resistor but changed my mind. Not that I noticed any sound difference.


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 14 posts ] 

All times are UTC - 7 hours

Fender Play Winter Sale 2020

Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to: