LSS Solo function doesn't work?

[Rockin_Ron]

I just recently purchased a used LSS. I've read through the online manual and scoped out this board, but can't seem to figure this out. It did not come with a foot switch so I used a standard 1 button latched type foot switch from another amp. I connected it to the rear channel plug and I can get that to work. When I connect it to the solo plug and enable the loop there doesn't seem to be any change in volume. In this mode I can adjust the level on the front panel output (last control stage after the master) but the solo pot doesn't seem to do anything. I'm playing a moderately low volume so does this make a difference? Does there suppose to be a significant volume change? I'm pretty much a newbie to MESAs and tube amps in general, so any help would be appreciated. I've ohmed out the cable and the switch (plus it works in the channel function so I know its good) What should I check? Could this V3 tube I've read about be dead or something?

Thanks

 

[prspastor]

Hi Rockin_Ron,
I'll try and help. From my understanding, the 1/4" jack on the back/bottom of the LSS is for switching on and off the reverb. The front foot pedal jack is a TRS (tip-ring-sleeve [or stereo]) jack. The Lonestar foot pedal has a channel switcher and a solo activator button on it. I'm not sure if the solo button is wired to the tip or the ring. You might be switching just the channel if you plug a tip-sleeve [mono] 1/4" plug into the foot switch jack. If you see the green channel light going on and off when you trip your foot switch, your switch is not going to turn on and off the solo.

Sounds like you will need a two button foot pedal with a TRS output AND a stereo cable to go to your amp. Or... if you are good with soldiering, you could create your own custom cable with two foot switches.

Hope this helps a bit...

 

[thom]

prspastor, the LSS has indeed a TRS footswitch plug on the front for a dual footswitch. It does however have sepeate footswitch jacks for the solo and channel change options.

Ron, have you activated the 'loop in' switch on the rear panel. I do believe you have to do this, and turn the loop level control up in order for the solo switch to work, yes even if you have nothing connected to the send return loop. The solo function is great, very noticeable, espescially at low levels.

 

[Rockin_Ron]

Thanks for your responses guys. I did have the loop in activated with the pot at 12 o'clock per the manual. Under these conditions I'm not hearing any volume boost. I was trying it from the rear jack because the manual said it should also work from there with a standard mono plug. Just trying to "poor boy" with the single switches for now. So according to the manual that should work. Wonder if I have other problems? Is it possible to screw something up inside if one put a mono plug in the stereo required input on the front panel? Anybody know how this tip-to sleeve to ring is wired to make both the channel and solo work? I've got a CRATE footswitch that has three separate latched switches (two tied to a stereo jack) and (one tied to a mono jack) that should work .... but doesn't.

 

[prspastor]

prspastor, the LSS has indeed a TRS footswitch plug on the front for a dual footswitch. It does however have sepeate footswitch jacks for the solo and channel change options.

Ron, have you activated the 'loop in' switch on the rear panel. I do believe you have to do this, and turn the loop level control up in order for the solo switch to work, yes even if you have nothing connected to the send return loop. The solo function is great, very noticeable, espescially at low levels.

My bad, I forgot about those jacks in the back.

To my understanding, I wouldn't think that putting a mono plug in a stereo jack would hurt anything at all. You would just ground out the ring. Now, I wouldn't have anything plugged into the front at the same time as you having something plugged in the back. Plugging into one might disable the other...

Sounds like something else is going on...

 

[JLBoogie]

You need to order a footswitch from Mesa and it would most likely solve the problem instead of all the time your spending trying to rig something, they are not that expensive especially after spending the money on a high dollar amp. Sometimes you just can't be cheap!

 

[plan-x]

Although I have a LSC, this is what the manuel says about those jacks.

These two 1/4” jacks provide an interface for remote control of the Channel Select
function as well as activation of the SOLO control. These jacks may be connected to an external control unit that stores a grounding
logic switch function under a midi program number, thereby removing the need to use the included LONE STAR Footswitch in larger stage rigs.
The EXTERNAL SWITCH jacks respond to any tip-to-ground latching type logic for their triggering. This type of switching logic can be found on most midi master control switching units on the market.

What the hell does that mean? :shock:

 

[Octavarius]

Although I have a LSC, this is what the manuel says about those jacks.

These two 1/4” jacks provide an interface for remote control of the Channel Select
function as well as activation of the SOLO control. These jacks may be connected to an external control unit that stores a grounding
logic switch function under a midi program number, thereby removing the need to use the included LONE STAR Footswitch in larger stage rigs.
The EXTERNAL SWITCH jacks respond to any tip-to-ground latching type logic for their triggering. This type of switching logic can be found on most midi master control switching units on the market.

What the hell does that mean? :shock:

It means that you can use a midi controlled switching unit, such as the Voodoo Lab GCX or the Axess Electronics CFX4, and use them in conjunction with these jacks. It's very simple; one cable from the unit switches one function. This is done by "closing" or "opening" the jack itself, in the sense that the device shorts the tip to the sleeve of the jack (closed), or going the other way; open. This corresponds to On/Off switching of functions like solo, or 1/2 switching of channels. Think of them as separate on/off cables for separate functions. It's basically just an analog switching solution for amps that don't incorporate any digital switching such as MIDI, and is brilliant for larger rigs where everything can be programmed and controlled with a single MIDI controller. Thus, one would be able to switch multiple channels, functions on and off on multiple amps, and even further combine that with effect processors and so forth, with only a single press on a button.

 

[phyrexia]

"latching type logic" = when the switch is closed, false (off), when the switch is open, true (on)

As opposed to a digital system where a momentary signal is used and a relay is turned on to close the circuit, I suppose.

 

[Rockin_Ron]

I still don't understand this footswitch connection and can't get it to work. When I review the schematics for the footswitch at schematic heaven it shows MESA drawings which show a standard 1/4 stereo plug wiring with the long part of the plug being ground. Yet in the Lonestar manual they keep calling it "tip to ground" Does that mean literally the tip should be ground. If so than their own schematics are wrong. Could someone take a picture of the inside of their footswitch showing the wiring? That would be most appreciated. Thanks!

 

[Octavarius]

I still don't understand this footswitch connection and can't get it to work. When I review the schematics for the footswitch at schematic heaven it shows MESA drawings which show a standard 1/4 stereo plug wiring with the long part of the plug being ground. Yet in the Lonestar manual they keep calling it "tip to ground" Does that mean literally the tip should be ground. If so than their own schematics are wrong. Could someone take a picture of the inside of their footswitch showing the wiring? That would be most appreciated. Thanks!

Regarding the "tip-to-ground"-logic, read my post above, and it should explain that, hopefully.

 

[plan-x]

Here's a gut shot. (LSC footswitch)

 

[Rockin_Ron]

Here's a gut shot. (LSC footswitch)

Thanks for the help plan-x. Appears like its what I expected. Tip & sleeve are (+) or "functions" while the long barrel of the plug is (-) or ground. I assume the topside of the board is just the switches, jack, and LEDs soldered to the board. I measured the voltages by inserting a stereo cord into the F/S jack in the front. I got 12 V off the sleeve and 11.37 V off the tip. I'm wondering now if something is hosed on the inside?

 

[plan-x]

I measured the voltages by inserting a stereo cord into the F/S jack in the front. I got 12 V off the sleeve and 11.37 V off the tip.

Getting the same on mine. How about the rear.

 

[Rockin_Ron]

I measured the voltages by inserting a stereo cord into the F/S jack in the front. I got 12 V off the sleeve and 11.37 V off the tip.

Getting the same on mine. How about the rear.

Hey thanks plan-x appreciate you confirming measurements. I just took these. I took the stereo plug out of the front and then plugged a mono plug into the rear jacks.

Chan = 1.42 - 1.43 V
Solo = 12.04 V

Could that be the problem? I thought the rear jacks are separate from the front F/S input. If you're getting the same at the front then I'm really baffled :roll:

 

[plan-x]

Ok, I'm getting 12v also on the rear solo. I pulled out my old morley switch and both my jacks in the rear work. Lets go over it again: For the rear solo, the loop switch has to be switched to "loop in"(up) and "Send level" in rear set to at least 12:00, mines at 1:00, and the solo vol(fr panel) has to be higher than the master. My master is set at 12:00 and my solo is set at 2:00. This gives me a slight boost, maybe 2-3db. And, it worked in all positions of the ch/fs mini toggle on the front.

Now if this fails to switch on to a louder vol, and does switches successfully in the rear "channel" jack(previously mentioned), indicating a good switch, then I would consider V3 as stated from your first post. If you have a efx pedal you might try it in the loop and see if that works, or try substituting V3 with a known good tube you may have. V4 is the reverb tube, if the reverb works, swap V4 with V3 and see what happens.

 

[Rockin_Ron]

Well, I tried activating the "solo" from the rear panel with a mono jack. I checked my settings against your suggestions and everything is set. I can't hear any discernible sound increase. I even pegged the solo level knob with the master at 12 ... and nothing. When I switched jacks to the "channel" on the rear, I could get it to switch channels.

But when I go to the front with a stereo jack ... I get nothing. No channel switching .... no increase in volume.

I pulled all the covers off all the preamps tubes and they all look the same (ie they all light up with the same intensity). I'm new to all this tube stuff, so I'll plead ignorance as to whether or not that means anything.

Would swapping V3 fix this, seems like I got something "funky" going on with the front jack since I get nothing. On the topside of the PCB on your pedal is there anything else going on besides just the components soldered directly into the board?

Thanks again for all your help!

 

[plan-x]

Confirming the loop works(or not) will help narrow down this problem to either, the loop, or the jack route. The way you called it on the PCB was correct, nothing else. Using my basic morley switch with a stereo cable in the front jack only switches the ch's, not the solo, revealing only the tip is being activated and the ring is not able to make contact on a mono FS. Using a wire, paper clip, with the stereo cable in front, I'm able to touch one end of the wire to the tip & the other to the ground & switch ch's. Likewise, touching the wire to the ring and ground will activate the solo. Also, do you have a manuel? Which gives the tube positions and functions. If not, here it is. http://www.mesaboogie.com/manuals/user_manuals.htm

 

[Rockin_Ron]

Confirming the loop works(or not) will help narrow down this problem to either, the loop, or the jack route. The way you called it on the PCB was correct, nothing else. Using my basic morley switch with a stereo cable in the front jack only switches the ch's, not the solo, revealing only the tip is being activated and the ring is not able to make contact on a mono FS. Using a wire, paper clip, with the stereo cable in front, I'm able to touch one end of the wire to the tip & the other to the ground & switch ch's. Likewise, touching the wire to the ring and ground will activate the solo. Also, do you have a manuel? Which gives the tube positions and functions. If not, here it is. http://www.mesaboogie.com/manuals/user_manuals.htm

I moved the mono cable and footswitch to the front panel and tried to activate the channel change ... but no go. This sort of mmics what you said to do with the paperclip. When I plug in the footswitch (which BTW worked on the rear panel to change channels) the green light goes out and channel switching does not work. I'm beginning to think I have a problem inside possibly with one of the relays. Looking at the schematics there is one inline to activate the solo function. I guess I should of suspected something when the seller said they didn't have the footswitch. I dread having to open this thing up. Oh well ... buyer beware. :x

I did check out the mesa site and downloaded that file already that you mention. Thanks plan-x.

 

[plan-x]

Ok, I used a mono cable with a single footswitch to replicate what you did, if my switch is closed, my green light goes off upon pluggin it in, I hit the switch and it goes on. Mini toggle(front panel) has to be in mid/up position (correction from "any position" previously stated) for switch to work. It may be a relay alright. I've opened mine up a couple times before. It's do-able. I think the paperclip test in a quite room, with a stereo cable is your best bet to hear if those relays are switching.
Before you go crackin the amp open, I would make sure your not overlooking the loop functionability. And is there a warranty still on it?