Help me understand master volume on my rumble combo

[NotHereNow]

I was experimenting with my rumble combo earlier today and I came across an unexpected situation. I was trying to bypass the preamp section of the amp by sending the signal from my MX5’s output through the effects return. My thought was to use the amp sim from the MX5 as the preamp along with effects, and disable the ir and use the rumble as my cab.

I had thought going into the effects return would put the signal from the MX5 into the power amp section, and that would be controlled by the master volume. While the signal did go through, turning the master up or down had no effect on the signal volume. As a matter of fact, as far as I could tell none of the controls on the amp did anything. I could only change the volume with the MX5’s controls.

Is there something strange going on here, or is this typical for combo amps? I always thought the gain and drive/level controls were in the preamp side and that the master knob controls the power amp side. Is that not the case? Does the effects return come in after the volume control? It seems odd to me that there isn’t a way to control the level of the effects loop on the amp itself. I don’t have any experience with other amp manufacturers so I’m not sure if this is a common situation or maybe just a rumble thing. Looking for advice on how to set up my amp to get the most versatility out of my modeler.

 

[gtirard]

Like you I would have thought that the master volume would still be effective when using the effects return, the behavior is counter intuitive.

 

[FearNoEvil65]

I was experimenting with my rumble combo earlier today and I came across an unexpected situation. I was trying to bypass the preamp section of the amp by sending the signal from my MX5’s output through the effects return. My thought was to use the amp sim from the MX5 as the preamp along with effects, and disable the ir and use the rumble as my cab.

I had thought going into the effects return would put the signal from the MX5 into the power amp section, and that would be controlled by the master volume. While the signal did go through, turning the master up or down had no effect on the signal volume. As a matter of fact, as far as I could tell none of the controls on the amp did anything. I could only change the volume with the MX5’s controls.

Is there something strange going on here, or is this typical for combo amps? I always thought the gain and drive/level controls were in the preamp side and that the master knob controls the power amp side. Is that not the case? Does the effects return come in after the volume control? It seems odd to me that there isn’t a way to control the level of the effects loop on the amp itself. I don’t have any experience with other amp manufacturers so I’m not sure if this is a common situation or maybe just a rumble thing. Looking for advice on how to set up my amp to get the most versatility out of my modeler.

Not sure but I think if you use the effects like that, whatever you plug in controls volume.
You could also ask on the Rumble thread, people there will know for sure
https://www.talkbass.com/threads/fender-rumble-club.1118826/page-2935

 

[Wasnex]

This is from the V3 Rumble Manual. The master comes unusually early in the circuit. Before the voicing filters, tone controls, and effects loop.

 

[BPotyk]

Which Rumble are you using?
What you described is exactly how I use mine.
I'm feeding a Rumble 800 with a Berg Super pre. Works just like you're expecting.
The master controls overall volume and the Hi/Lo power switch still effects the output.

 

[NotHereNow]

Im using a rumble 200 combo. The diagram is helpful but I’m surprised that there is no adjustability for the effects loop on the unit. Most modulation and delay pedals I’ve seen don’t have a level control. At the same time I guess they don’t typically boost the signal either so I guess most of the time it doesn’t matter? Does anyone know if this is how effects loops are wired on other amps?

 

[happygilmour]

I was experimenting with my rumble combo earlier today and I came across an unexpected situation. I was trying to bypass the preamp section of the amp by sending the signal from my MX5’s output through the effects return. My thought was to use the amp sim from the MX5 as the preamp along with effects, and disable the ir and use the rumble as my cab.

I had thought going into the effects return would put the signal from the MX5 into the power amp section, and that would be controlled by the master volume. While the signal did go through, turning the master up or down had no effect on the signal volume. As a matter of fact, as far as I could tell none of the controls on the amp did anything. I could only change the volume with the MX5’s controls.

Is there something strange going on here, or is this typical for combo amps? I always thought the gain and drive/level controls were in the preamp side and that the master knob controls the power amp side. Is that not the case? Does the effects return come in after the volume control? It seems odd to me that there isn’t a way to control the level of the effects loop on the amp itself. I don’t have any experience with other amp manufacturers so I’m not sure if this is a common situation or maybe just a rumble thing. Looking for advice on how to set up my amp to get the most versatility out of my modeler.

My rumble 500 head does the same thing.

 

[DrBnz]

I do the same thing... I run thru a pedal board and then to the amp return port. At this point the amp is at max and everything is controlled by the pedal board (or your bass). Rumble 200 or 500 - same results

 

[Guitalia]

This is from the V3 Rumble Manual. The master comes unusually early in the circuit. Before the voicing filters, tone controls, and effects loop.
View attachment 7101093

Haven't looked at the manual, but I would hope that centering the active EQ controls corresponds to flat settings and that the manual explains that.

 

[andare]

Which Rumble are you using?
What you described is exactly how I use mine.
I'm feeding a Rumble 800 with a Berg Super pre. Works just like you're expecting.
The master controls overall volume and the Hi/Lo power switch still effects the output.

Afaik The 800 changed a few behaviors that people complained about, like the Master volume affecting the effects loop. They also added a switch to control whether the Master affects the DI. Previously the DI was only post pre and post master.

 

[micguy]

Haven't looked at the manual, but I would hope that centering the active EQ controls corresponds to flat settings and that the manual explains that.

You would hope that, but....while the ACTIVE EQ section is flat when the knobs are centered, there is a fixed "tone stack" that's always in the circuit as well. The net result is, if you set the EQ knobs all to noon, it's not flat. It's not even close - it's quite scooped (like most Fender amps with their knobs centered). You need to set the bass and treble well below half, and the mids well above half to get it close to flat. It's never completely flat, you just can't get there with the controls you have, but you can get close.

 

[agedhorse]

It depends on the Rumble model, but other than the 800, the effects return is post master volume. It’s just the way the designer designed it.

 

[Deleted member 409896]

I think this must be a common design for combo amps.

My Markbass Black Line CMB101 doesn't have an "effects" input or output, but it does have an Aux In jack, and it behaves the same way. None of the knobs, including Master, has any effect on the Aux In signal.

 

[jthisdell]

The design for Rumble's are a little unusual, you can see that the Line Out (i.e. DI) is also post master, so if you turn your stage volume up you also turn up your FOH signal. It works OK you just have to be aware of this.

 

[G-Dog]

All Rumble questions are welcome in the TalkBass Fender Rumble Club. Lots of helpful, knowledgeable Rumblers there. Get a free membership with keys to all Rumbling wisdom and knowledge to all Rumble owners! Just tell us which model you have. No pix required, though they are encouraged and appreciated.

 

[Miles_ONeal]

You would hope that, but....while the ACTIVE EQ section is flat when the knobs are centered, there is a fixed "tone stack" that's always in the circuit as well. The net result is, if you set the EQ knobs all to noon, it's not flat. It's not even close - it's quite scooped (like most Fender amps with their knobs centered). You need to set the bass and treble well below half, and the mids well above half to get it close to flat. It's never completely flat, you just can't get there with the controls you have, but you can get close.

Correct. This is all covered in the Rumble Club Wiki. Flat in the amp (ignoring speakers) is roughly 10 2 2 10 bass to treble.

 

[Miles_ONeal]

I can see where it could be frustrating, but it also works extremely well for some situations, such as using a second Rumble as a slave; the first amp’s controls are all that matters.

 

[micguy]

Correct. This is all covered in the Rumble Club Wiki. Flat in the amp (ignoring speakers) is roughly 10 2 2 10 bass to treble.

That's 10 O'clock, and 2 O'clock, not full and 20% rotation. It's not completely flat, it's....close - where the various eq set points, are in the different circuits, you can't actually get completely flat with the knobs you have.