Mesa Subway TT-800 : no sound from Subway channel

[he77kat_]

As I mentioned in a separate thread, I recently purchases a Mesa/Boogie Subway TT-800. I love the amp so much, the Boogie channel has that deep vintage bloom that I love, and playing through a punchy Phil Jones 8x5 is the icing on the cake.

However, I bought the amp new and since I received it the Subway channel has never worked. Switching to that channel results in silence. The tech support rep at Sweetwater suggested switching the V2 and V3 tubes to test if the Boogie channel dies and the Subway channel starts working, but unfortunately there was no change. I also tried using a generic footswitch, but still nothing.

The interesting thing is, running my bass cable to the RETURN of the FX Loop for the Subway channel does result in sound output. This leads me to believe that the preamp for the Subway channel is broken somehow, but if it's not a tube issue, what other troubleshooting steps might I take?

NOTE: Sweetwater has offered to replace the amp, but they won't have more stock until the end of the month or longer. I'd rather keep this amp and fix it if I can. Any suggestions are appreciated.

 

[gtirard]

@agedhorse will soon bring the light. I think the Subway chanel doesn't use tubes, so it's not surprising that changing the tubes didn't fix anything, I'm more surpirsed that the Sweatwater tech support asked you to try that.

 

[lermgalieu]

@agedhorse will soon bring the light. I think the Subway chanel doesn't use tubes, so it's not surprising that changing the tubes didn't fix anything, I'm more surpirsed that the Sweatwater tech support asked you to try that.

Both channels use tubes.

 

[he77kat_]

@agedhorse will soon bring the light. I think the Subway chanel doesn't use tubes, so it's not surprising that changing the tubes didn't fix anything, I'm more surpirsed that the Sweatwater tech support asked you to try that.

In this thread it is mentioned that the Boogie channel uses the V2 tube and the Subway channel uses V3.

 

[gtirard]

In this thread it is mentioned that the Boogie channel uses the V2 tube and the Subway channel uses V3.

Ok, I could be wrong then. Agedhorse (the designer of the amp, and active TB member) will soon clarify this.

 

[agedhorse]

First, try installing a 1/4” patch cord between the Subway channel effects send and return jacks. If it now works, it’s possible that the internal return jack switch is damaged.

There’s nothing else user repairable, we can either fix it under warranty at the factory or your dealer can exchange the amp when they get new ones in.

 

[agedhorse]

Ok, I could be wrong then. Agedhorse (the designer of the amp, and active TB member) will soon clarify this.

Both channels use tube gain stages.

 

[he77kat_]

First, try installing a 1/4” patch cord between the Subway channel effects send and return jacks. If it now works, it’s possible that the internal return jack switch is damaged.

There’s nothing else user repairable, we can either fix it under warranty at the factory or your dealer can exchange the amp when they get new ones in.

Much appreciated. I'll give that a try and see what's what.

 

[he77kat_]

Ran a patch cable between Subway channel FX SEND and RETURN. No change -- still silent. If you crank the volume you can hear a low white noise get louder, so the signal chain must just be broken somewhere. Looks like I'll have to swap it out with Sweetwater when they receive more stock

 

[agedhorse]

It's possible that something got damaged in a shipping tumble, happens occasionally.

 

[he77kat_]

It's possible that something got damaged in a shipping tumble, happens occasionally.

Yeah no doubt. Fwiw, I've tried four different class D amps in the past month and the Mesa blows the others out of the water. It's not even close. If I have to wait a few weeks to get a new one I'm perfectly happy to do that.

 

[MCF]

As I mentioned in a separate thread, I recently purchases a Mesa/Boogie Subway TT-800. I love the amp so much, the Boogie channel has that deep vintage bloom that I love, and playing through a punchy Phil Jones 8x5 is the icing on the cake.

However, I bought the amp new and since I received it the Subway channel has never worked. Switching to that channel results in silence. The tech support rep at Sweetwater suggested switching the V2 and V3 tubes to test if the Boogie channel dies and the Subway channel starts working, but unfortunately there was no change. I also tried using a generic footswitch, but still nothing.

The interesting thing is, running my bass cable to the RETURN of the FX Loop for the Subway channel does result in sound output. This leads me to believe that the preamp for the Subway channel is broken somehow, but if it's not a tube issue, what other troubleshooting steps might I take?

NOTE: Sweetwater has offered to replace the amp, but they won't have more stock until the end of the month or longer. I'd rather keep this amp and fix it if I can. Any suggestions are appreciated.

I would just endure the wait and have SW replace it. Frankly that’s one reason I use them. They can’t help the supply chain backlog. And I’m sure Mesa is doing everything they can to get the product out.

The TT is worth the wait.

 

[logdrum]

There are Mesanites, little AI gremlins hiding in the layers of the sheet metal that are giving you are a hard time because you did not use a Mesa Subway Cab.

 

[he77kat_]

There are Mesanites, little AI gremlins hiding in the layers of the sheet metal that are giving you are a hard time because you did not use a Mesa Subway Cab.

Lmaoo well shoot, maybe pulling the trigger on that Mesa 215 I've had my eye on will cure all this nonsense

 

[Al Kraft]

Lmaoo well shoot, maybe pulling the trigger on that Mesa 215 I've had my eye on will cure all this nonsense

Even if it doesn't fix your current issue (highly unlikely IMO) that 215 will put a huge smile on our face while you wait for the replacement head and use the Boogie channel on the one you have!

 

[MCF]

Even if it doesn't fix your current issue (highly unlikely IMO) that 215 will put a huge smile on our face while you wait for the replacement head and use the Boogie channel on the one you have!

Or the 410. Highly recommended.

 

[he77kat_]

Or the 410. Highly recommended.

The 410 was actually my first pick, but I already have the PJB 8x5. I figured it would be cool to run like a 212 or a 215 as a "best of both worlds" kinda thing. I haven't gone too far down the rabbit hole of "many little speakers" vs "a couple big ones" yet, any advice I should be aware of?

 

[MCF]

The 410 was actually my first pick, but I already have the PJB 8x5. I figured it would be cool to run like a 212 or a 215 as a "best of both worlds" kinda thing. I haven't gone too far down the rabbit hole of "many little speakers" vs "a couple big ones" yet, any advice I should be aware of?

Can’t help you there. I’m a 410 kind of guy. A few here have both. I defer to them for good advice. All I can say is I absolutely love the Subway 410.