Double Bass PJB Double Four Question

[BobKay]

I own and really like my Double Four; form and function have been fine for me. But I've recently encountered a confusing situation: the level of the line out jack signal seems to be controlled by the master volume control.

In other words, if I run an instrument cable from the line out to a PA board, adjust the master volume control to 12 o'clock, and then set the volume on the PA, everything is fine. But, if I want to turn down the stage volume, by turning the master volume control down, the volume through the PA also decreases. That is different than any other amp I'm familiar with. The line out signal is usually a level signal regardless of the stage volume.

So, my questions:
1. Is the amp operating properly? Perhaps a manufacturing error?
2. If I want to lower the stage volume and not affect the PA level, should I turn down the gain on the amp, instead of the master volume.
3 Anybody else experience this?

I know that I can avoid this by using a DI, running the XLR to the board and an instrument cable from the output jack. But it is one more thing to deal with.

Of course I'll contact PJB next week when they are open. And I'll try the above at a gig tonight where I don't usually use the amp as a stage monitor, but I will tonight to try and answer my questions.

 

[dylanjohnson]

I've never run mine through the line out, but I'm sorry to hear this.

 

[Killing Floor]

I've never run mine through the line out, but I'm sorry to hear this.

Same.
It makes sense since due to limited real estate. I'll try to check mine this weekend.

 

[BobKay]

Update from tonight’s gig: behavior was the same as last night. Different PA, so that eliminates the possibility of a problem with just a specific PA.

I also tried turning the stage volume down by reducing the input gain - didn’t work. The PA volume also reduced.

So, I’ll call PJB next week.

 

[Ric Vice]

My guess is that, as you mentioned, the Master Volume adjusts the line out while the DI is unaffected. That way when you lower (or raise) the amp on stage you don’t impact the FOH mix. I’ve had a similar problem with the Headway EDB-2 as the line out doesn’t have a separate gain control, so you can’t lower (or raise) the volume onstage without dropping the the FOH volume. My workaround was to get one of those guitar cords with a built in passive volume control, it works but the it isn’t an ideal solution and your setup is different.

 

[bherman]

The situation you described is not uncommon - the Quilter BB800 does the same thing. I played a gig last night with the amp lined out to the pa, and the sound guy wasn’t getting enough volume. Ultimately needed to turn up the master and lower the volume on my bass (I was using a P bass) to compensate. Took some fiddling to get it balanced right, but we ultimately found a sweet spot. One solution that I’ve used is a separate DI. Might be worth checking with PJB to see if they have a suggestion.

 

[Ric Vice]

The situation you described is not uncommon - the Quilter BB800 does the same thing. I played a gig last night with the amp lined out to the pa, and the sound guy wasn’t getting enough volume. Ultimately needed to turn up the master and lower the volume on my bass (I was using a P bass) to compensate. Took some fiddling to get it balanced right, but we ultimately found a sweet spot. One solution that I’ve used is a separate DI. Might be worth checking with PJB to see if they have a suggestion.

I wouldn't have thought of that but it makes perfect sense. There is definitely a difference between the DI included in many amplifiers and a quality outboard DI from someone like Radial and Countryman. I've had to change preamps occasionally between my older Headway EDB-2 and my 3 Leaf Audio enabler when
the FOH wasn't getting enough signal to work with.

 

[wagdog]

I believe the line out on the D4 is not meant as a DI proper but more for daisy chaining amps together. PJB used to make powered speakers that utilized this function. If you needed to make a volume adjustment it only needed to be done on the D4 and the slave would follow suit.

 

[Neon Scribe]

Yeah, it looks like the Double Four doesn't have a DI out, so your best course of action is probably adding a separate DI box in front of it.

 

[Don Hergert]

I have one of these permanently attached to my piezo/pre-amp outbound connection. So I can always connect signal to both my amp and a FOH at the same time. No amp-output dependencies.

 

[BobKay]

The amp does not have a DI, only a line out. I already have several pre-amps with DI, so I know I can work around the issue. I can do it with my RedEye or the PJB PE5 I own.

Just slightly frustrating to have to add one more piece. Not a game changer since the D4 sounds great.

 

[Ric Vice]

The amp does not have a DI, only a line out. I already have several pre-amps with DI, so I know I can work around the issue. I can do it with my RedEye or the PJB PE5 I own.

Just slightly frustrating to have to add one more piece. Not a game changer since the D4 sounds great.

Bob Kay,
I’ve dealt with this for years because I previously owned two different Walter Woods amplifiers, neither of which had a DI I generally just went with whatever DI
the sound company provided, most had a Countryman 75 or something similar I never had an issue. Fortunately for me the Woods line out has a pre/post switch
so I generally didn’t have to deal with varying sound levels at my amp. The RedEye is most likely the best solution and only a small inconvenience.