ProSoundWeb Community

Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => Wireless and Communications => Topic started by: frank kayser on June 12, 2019, 02:49:47 PM

Title: Acoustic guitar into Senn Beltpack Transmitter
Post by: frank kayser on June 12, 2019, 02:49:47 PM
Hi again,
Coming from the wired world, I'm used to using a DI box to interface the acoustic guitar (as an example) to the board.  Passive DI for active pickups, and active DI for passive (e.g., K&K) pickups is the general rule of thumb.


One thing I'm aware of is that the passive K&K and the like, need something with very high input impedance so as not to lose the bottom end of the instrument.  Something like a Baggs Paracoustic, or Radial Piezo work well.


So...


I know plugging a active pickup into the Senn (and others) beltpack with the appropriate cord is no issue, but how does one handle a passive pickup?  Does the beltpack offer high enough impedance on its own?  Plug it in downstream of an active DI (battery, self powered, of course)?


Ho do you work with this?


frank
Title: Re: Acoustic guitar into Senn Beltpack Transmitter
Post by: Ike Zimbel on June 12, 2019, 03:40:22 PM
Hi again,
Coming from the wired world, I'm used to using a DI box to interface the acoustic guitar (as an example) to the board.  Passive DI for active pickups, and active DI for passive (e.g., K&K) pickups is the general rule of thumb.


One thing I'm aware of is that the passive K&K and the like, need something with very high input impedance so as not to lose the bottom end of the instrument.  Something like a Baggs Paracoustic, or Radial Piezo work well.


So...


I know plugging a active pickup into the Senn (and others) beltpack with the appropriate cord is no issue, but how does one handle a passive pickup?  Does the beltpack offer high enough impedance on its own?  Plug it in downstream of an active DI (battery, self powered, of course)?


Ho do you work with this?


frank
I would just go ahead and try it. I haven't noticed any issues in the past, and, the pack is the functional equivalent of an active DI (in that it has an electronic input rather than a transformer). You would need to check specs to see the actual input impedance. Also, if you scroll through the menus, some systems have "cable emulation" which try to mimic...wait for it...cables (and their loading effect on a pick up).
One thing you do need to be aware of is that if the pack is digital, it may induce all sorts of unwanted noise into the pick-up.
Title: Re: Acoustic guitar into Senn Beltpack Transmitter
Post by: Russell Ault on June 12, 2019, 05:06:33 PM
I know plugging a active pickup into the Senn (and others) beltpack with the appropriate cord is no issue, but how does one handle a passive pickup?  Does the beltpack offer high enough impedance on its own?

According to the spec sheet, the SK 100 G3 has a line input impedance of 1 MΩ, which really ought to do it.

-Russ
Title: Re: Acoustic guitar into Senn Beltpack Transmitter
Post by: Tim Hite on June 12, 2019, 08:18:19 PM
K&K Maes these, seems like the hot ticket. . .

https://kksound.com/products/purexlrpreamp.php#simple2

Title: Re: Acoustic guitar into Senn Beltpack Transmitter
Post by: brian maddox on June 12, 2019, 09:54:39 PM
i've plugged my K&K into several different wireless systems with no issue.  Granted, none of those have been the Senn, but i wouldn't expect any problem.
Title: Re: Acoustic guitar into Senn Beltpack Transmitter
Post by: Mike Caldwell on June 13, 2019, 08:47:51 AM
The later Sennheiser wireless packs have a guitar cable emulation mode.
Title: Re: Acoustic guitar into Senn Beltpack Transmitter
Post by: Scott Helmke on June 13, 2019, 10:17:52 PM
The later Sennheiser wireless packs have a guitar cable emulation mode.

Doesn't that *lower* the impedance to simulate a guitar amp input?
Title: Re: Acoustic guitar into Senn Beltpack Transmitter
Post by: Russell Ault on June 13, 2019, 10:55:07 PM
Doesn't that *lower* the impedance to simulate a guitar amp input?

Sounds like (https://www.youtube.com/watch?v=mM7UtXbGdlo) it's mostly a capacitance change (if anything, using a longer cable should result in a higher impedance, unless I'm missing something).

-Russ
Title: Re: Acoustic guitar into Senn Beltpack Transmitter
Post by: Mike Caldwell on June 14, 2019, 09:19:21 AM
Doesn't that *lower* the impedance to simulate a guitar amp input?

It changes the input capacitance, not sure what the range of adjustment is, never used that function.

Another "feature" for guitar players, the Sennheiser receivers have a built in guitar tuner. I wonder how many people actually use it.
Title: Re: Acoustic guitar into Senn Beltpack Transmitter
Post by: frank kayser on June 14, 2019, 07:24:30 PM
According to the spec sheet, the SK 100 G3 has a line input impedance of 1 MΩ, which really ought to do it.

-Russ


Thanks, Russ, for the spec.  I hate to admit, but the capacitance change vs cable length is a bit above my pay grade...
I would just go ahead and try it. I haven't noticed any issues in the past, and, the pack is the functional equivalent of an active DI (in that it has an electronic input rather than a transformer). You would need to check specs to see the actual input impedance. Also, if you scroll through the menus, some systems have "cable emulation" which try to mimic...wait for it...cables (and their loading effect on a pick up).
One thing you do need to be aware of is that if the pack is digital, it may induce all sorts of unwanted noise into the pick-up.
Good point.  Trying it is easier said than done.  I have a K&K on my box, but it's hard-wired into a K&K Pure Preamp (pre 2015).  Facing one "in the wild" seems to happen only a couple times/year.  Digital introducing noise?  Hmmm... Something to look out for.
i've plugged my K&K into several different wireless systems with no issue.  Granted, none of those have been the Senn, but i wouldn't expect any problem.
Well, it seems unanimous.  Not a worry. Senn. Shure. AT. Lectrosonics.  They probably all function very similarly.
It changes the input capacitance, not sure what the range of adjustment is, never used that function.

Another "feature" for guitar players, the Sennheiser receivers have a built in guitar tuner. I wonder how many people actually use it.
Count on one hand? I can't see that being any of the following - quick, easy, or convenient.  Tough to beat a clip-on tuner...


Thanks everyone,
frank






Title: Re: Acoustic guitar into Senn Beltpack Transmitter
Post by: Scott Helmke on June 15, 2019, 11:47:46 AM
Senn. Shure. AT. Lectrosonics.  They probably all function very similarly.

Digital UHF is quite a bit different, actually. If you're using something like Shure ULX-D or Axient Digital you might notice a hissing noise in the signal if the pickup is being affected.   The Crown 311 headsets we still have can only be used with analog wireless, for instance.  And we had to replace some of the older lavs and handheld heads.
Title: Re: Acoustic guitar into Senn Beltpack Transmitter
Post by: MikeHarris on June 15, 2019, 05:11:10 PM
Digital UHF is quite a bit different, actually. If you're using something like Shure ULX-D or Axient Digital you might notice a hissing noise in the signal if the pickup is being affected.   The Crown 311 headsets we still have can only be used with analog wireless, for instance.  And we had to replace some of the older lavs and handheld heads.

Curious what you hear when you plug the TA4F of the crown into a ULXD or Axient .Analog should be the same..??
Title: Re: Acoustic guitar into Senn Beltpack Transmitter
Post by: Scott Helmke on June 15, 2019, 09:18:29 PM
Curious what you hear when you plug the TA4F of the crown into a ULXD or Axient .Analog should be the same..??

You hear a hissing noise with digital.
Title: Re: Acoustic guitar into Senn Beltpack Transmitter
Post by: Tim Hite on June 15, 2019, 10:57:42 PM
The Lectrosonics Digital Hybrid is different in that it's using digitally encoded audio over an analog carrier, so none of the disadvantages of pure digital wireless systems.

There are a bunch of artists using Lectrosonics gear to get from their instruments to their pedalboards and amps with no noise issues.

I would imagine it's the same with the Crown 311.

Digital UHF is quite a bit different, actually. If you're using something like Shure ULX-D or Axient Digital you might notice a hissing noise in the signal if the pickup is being affected.   The Crown 311 headsets we still have can only be used with analog wireless, for instance.  And we had to replace some of the older lavs and handheld heads.