SF-2 & rig help

[hollis]

Mike,  
 
Do you notice any signal loss through the wireless set up?

[dadabass2001]

Hi Hollis,
I'm not seeing it in terms of level at all. There's an output level adjust on the receiver  to compensate for any drop, but it has no unity setting, and where I've got it set there's no level drop.  
There may be some frequency loss, but I can't hear it in a live bar setting with the rest of the band going. My lead guitarist always sets up next to me, with the drummer on my other side, then the second guitarist, and sax/keyboard player out at the other end.  
Mike

[David Houck]

Mike; I've been avoiding having the tuner in the signal chain since, as a general rule, the more stuff you have in the chain the more noise you introduce into the chain.  I'll A/B it today and see if having the tuner in the chain add's any discernable noise.  If not, then I'll go with that solution; perhaps sticking it somewhere in the effects loop.

[cntrabssn]

Dave,  
 
It sounds like you may be on the way to a solution, but I just wanted to add a couple of things:  
 
I don't think the phase of the signal feeding the tuner makes a difference here, since the tuner sees only a single input signal. Also, I'm not sure that attempting to flip the phase with a cable will work, or is a good idea. The crossover and full range outputs are single-ended, referenced to ground. A reverse wired cable will essentially short the output driver to ground through the input of the tuner. At best, you'll get no signal at the tuner. At worst, you could get no signal and a damaged output device. Someone please correct me if I'm wrong about this.
 
I'm wondering if your problem is related to the level or harmonic content of the signal feeding the tuner. You could see if the tuner behaves differently depending on your volume setting. Also , as Werner said, tuners like to see a simple signal, as pure as possible. Perhaps running the tuner post EQ (SF & F1-X) is freaking it out. Since you're already using the low pass output, experimenting with the crossover frequency might help.  
 
- nate.
 
(Message edited by cntrabssn on October 16, 2004)

[David Houck]

Nate; thanks for the response.
 
On your first point.  Some of the members here are running one cabinet out of the full range output and a subwoofer out of the low-pass output.  To do that they are reversing the phase out of the low-pass side (to eliminate the distortion that otherwise occurs).  How does that situation differ from the one I was describing.
 
I think you are right that the tuner was freaking out, an apt description, running post EQ.  There are several components affecting both level and harmonic content in the chain.
 
I did try placing the tuner in the chain between the bass and the F-1X; and I could not hear any additional noise.  So, that's where I'm going to leave it.
 
Another day, another lesson learned.

[cntrabssn]

Dave,
 
To correct for the phase difference between the full range and crossover outputs, you need to reverse the phase at one set of speaker terminals. Note that if the F1-X line outputs were balanced and you were using balanced power amplifier inputs, you would be able to invert the phase on one of the interconnects between the F1-X and the power amp. In this case, we're compensating for phase cancellation that results from trying to use two signals that aren't phase coherent.
 
This situation differs from your tuner scenario because there is only one signal we're worried about, not two. You're just sending a signal to the tuner that you don't intend to use elsewhere. Since the tuner sees only one signal (e.g. low pass from F1-X), there's nothing else to cause the phase cancellation at the tuner input.
 
By the way, you should also be able to use the tuner as the first device in your effects loop without difficulty. You'll get the benefit of using the first half of the tube as a buffer.
 
I hope this helps.
 
- nate.
 
 
 

[David Houck]

Nate; thanks for a clear explanation.  For the moment, I understand; but I'm sure I'll forget again in the future .