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Old 06-24-2021, 06:55 AM
SongwriterFan SongwriterFan is offline
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Default K&K / Ultratonic into low impedance DI woes (again)

I have an earlier post about my K&K equipped Martin 000-18 GE that had an issue at one venue. The issue was determined to be the low impedance (50kohm) DI that was at that venue.

The problem was solved when I put the K&K preamp in front of the DI.

In the meantime, I upgraded the K&K to an Ultratonic pickup (also had the neck reset on the guitar). I also have a ToneDexter, but haven't had a chance yet to get an IR that I like with it.

On Tuesday night, the Ultratonic to wireless transmitter to K&K preamp to Baggs Align EQ pedal seemed to work just fine at one venue. So on Wednesday night, I took it back to the "problem venue" thinking things should be fine. Enter Mr Murphy.

Once again, the guitar had NO bass (like a high-pass filter at a high frequency was in place). I took out the EQ pedal and just used the K&K preamp. I even took out the wireless system and went with cords.

What we did NOT try (didn't think of that until much later) was just to move my preamp over to the "board" and bypass their DI entirely.

At any rate, I have no clue as to why this system behaved in this manner. I even tried a different DI (same brand, just a different box). Tried each of the inputs.

I guess I should've just taken the ToneDexter and tried to use it (with a not-so-good image that I'd managed to make so far, or maybe just bypass it) and use the DI out on the ToneDexter . . but I left that at home since I wasn't ready to use it. And I didn't want to introduce another variable in case something didn't work right.

And if one more person (like somebody last night) says "take out the K&K and put in a Baggs", I'm gonna scream!

This is very frustrating. The problem just seems so inconsistent, and I can't figure out why this should be an issue at all since I was using the K&K preamp. Would upgrading to the Ultratonic negate its effect? Seems doubtful.

Also, I've used this system at home (into a Fishman Loudbox) and it was used at the guitar store to help me set the EQ pedal, and it worked perfectly in those settings.

Something about their DI box (surely it's not their Behringer Wifi mixer?) just seems to hate working with my setup. And yet it worked before (using the K&K preamp and K&K Mini before the Ultratonic).

Next week I'm taking the ToneDexter (hopefully will have a better IR image by then) and go through its DI. Surely that will solve the issue? Even if I bypass the Tonedexter image?
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  #2  
Old 06-24-2021, 08:52 AM
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James May James May is offline
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Whether it be a K&K or an Ultra Tonic, if you plug into something and you are getting a thin, "no bass" kind of sound, it almost certainly means you've plugged directly into a line level input with a 10K impedance or so. That will zap the bass response.

I'm not sure how any proper DI could be made to present such a low impedance unless it has a line level switch engaged by accident.

And yes, using ToneDexter, if only on bypass, would have prevented this.
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Old 06-24-2021, 09:07 AM
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Thanks, James.

This is the actual DI that they have at that venue. It's labeled as 50 kohm.

https://www.seismicaudiospeakers.com...cts/direct-box

I have no idea what the "PARPOUT" is (though sometimes they've plugged into that). I moved it to the "INPUT" and it didn't make any difference.

Next time, I will bring the ToneDexter (I have it on a small pedalboard with an EQ in the effects loop, and a rechargeable battery system to power everything).

I will just take their XLR output and plug it directly into the DI output of the ToneDexter. Hopefully that will solve all the issues.

I just cannot figure out why the DI would cause this issue if I'm going through the K&K preamp first. Or why the issue is so inconsistent. It used to sound fine without the preamp. Then when it became an issue, the preamp fixed it. But now the issue is back even with the preamp.

I suppose all that shouldn't bother me (as long as the ToneDexter fixes it) . . but as an engineer, it bothers the heck out of me. The tools I had on hand should have fixed the issue . . but clearly did not.
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Old 06-24-2021, 09:15 AM
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BTW, this is the "board" that they are using.

https://www.behringer.com/product.html?modelCode=P0BI8

I just noticed on the picture that inputs 1 and 2 are labeled "Hi-Z" and that the inputs are all "combo" 1/4" and XLR . . . maybe that's also part of the issue.

I was not going into input 1 or 2 last night. Maybe when I had no problems, I was in one of those inputs?

Now that you know what I'll be going into (at that venue), coming directly out of the ToneDexter DI is the way to go to avoid issues, right? And I assume I should set it up so the DI is a constant output (not linked to the output level knob)?

And just to make sure I understand . . . . when in "bypass" mode, the only thing I'm bypassing is the IR image processing, right? I would still be getting the pre-amp boost from the input level knob, and the EQ I have in the effects loops would still be working?

Thanks for all your help.
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Old 06-24-2021, 12:26 PM
Gordon Currie Gordon Currie is offline
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Quote:
Originally Posted by SongwriterFan View Post
Thanks, James.

This is the actual DI that they have at that venue. It's labeled as 50 kohm.

https://www.seismicaudiospeakers.com...cts/direct-box
50K ohm is too low of an impedance to plug your pickup into, but it should work going into a preamp first.

I own the 12 channel version of the mixer you referenced. I go from my passive SBT into the ToneDexter, and from the ToneDexter DI out into an input channel on the XR12.

Need to set that input channel to Line. Works fine.

Are you sure you were plugged into the K+K preamp AND it was going into the DI? The sound you describe is exactly what I have experienced plugging into a passive DI.
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Old 06-24-2021, 12:37 PM
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Quote:
Originally Posted by SongwriterFan View Post
Thanks, James.

This is the actual DI that they have at that venue. It's labeled as 50 kohm.

https://www.seismicaudiospeakers.com...cts/direct-box

I have no idea what the "PARPOUT" is (though sometimes they've plugged into that). I moved it to the "INPUT" and it didn't make any difference.
...
That particular DI is designed for keyboards and guitars with ACTIVE electronics. They can drive 50K with no problem. It will not work properly with a passive pickup, as you seem to have experienced.

If you were using the K&K preamp (or any other preamp) before this DI, it should have worked fine, so there is still a mystery there.
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Old 06-24-2021, 12:42 PM
Gordon Currie Gordon Currie is offline
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Quote:
Originally Posted by SongwriterFan View Post
Now that you know what I'll be going into (at that venue), coming directly out of the ToneDexter DI is the way to go to avoid issues, right? And I assume I should set it up so the DI is a constant output (not linked to the output level knob)?
Yes, connect the DI output directly to an input channel. DO NOT USE THE SEISMIC AUDIO DI.

If I am running my own sound, I prefer to switch off 'constant volume' so I can have a quick adjustment in the middle of a performance. Otherwise 'constant volume' presents the optimal signal to the mixer.

Quote:
Originally Posted by SongwriterFan View Post
And just to make sure I understand . . . . when in "bypass" mode, the only thing I'm bypassing is the IR image processing, right? I would still be getting the pre-amp boost from the input level knob, and the EQ I have in the effects loops would still be working?
Yes, you are correct. ToneDexter is not 'true bypass' like certain fx pedals, nor does it need to be.
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Old 06-24-2021, 01:18 PM
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Quote:
Originally Posted by Gordon Currie View Post
Are you sure you were plugged into the K+K preamp AND it was going into the DI? The sound you describe is exactly what I have experienced plugging into a passive DI.
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Originally Posted by James May View Post
If you were using the K&K preamp (or any other preamp) before this DI, it should have worked fine, so there is still a mystery there.
Yep, the final chain we ended up using was: K&K(upgraded to Ultratonic) > cable > K&K preamp (the one designed to clip to your belt) > cable > 50k input DI > XLR input on Behringer mixer.

Exactly like I'd done there before (with no issues) . . but this time it sounded just like NOT having the preamp in-line.

I thought maybe the battery was dead on the pre-amp, but when I took it out of the chain, my signal dropped a LOT going into the board (based on what the guy running sound said).

Definitely a a mystery.
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Old 06-24-2021, 01:22 PM
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Quote:
Originally Posted by Gordon Currie View Post
I own the 12 channel version of the mixer you referenced. I go from my passive SBT into the ToneDexter, and from the ToneDexter DI out into an input channel on the XR12.

Need to set that input channel to Line. Works fine.
Thanks!

So there's a setting on each channel for line/mic? It doesn't do that automatically depending on whether you're plugging in an XLR cable or 1/4" cable?

I guess I should download the manual for their mixer . . and what the heck, download the app so I can play around with it (at home) and see what all is available. I bought the Mackie equivalent (though it's set up like a mixer board) . . . which means everybody else uses the Behringer, of course.
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Old 06-24-2021, 04:08 PM
Gordon Currie Gordon Currie is offline
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Quote:
Originally Posted by SongwriterFan View Post
So there's a setting on each channel for line/mic? It doesn't do that automatically depending on whether you're plugging in an XLR cable or 1/4" cable?
No, how would it 'know' whether the XLR you plugged in is coming from a microphone or a ToneDexter?

This needs to be set within the mixer app.
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Old 06-24-2021, 06:35 PM
phcorrigan phcorrigan is offline
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I will just take their XLR output and plug it directly into the DI output of the ToneDexter. Hopefully that will solve all the issues.
Make sure you set the DI switch on the back to "VAR," then start with the "output level" control set to the mid point or lower. The DI "Fixed" output is pretty hot! I just go through the instrument output, since the XLR input on some mixers is mic-level only.
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Old 06-25-2021, 06:04 AM
SongwriterFan SongwriterFan is offline
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Quote:
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No, how would it 'know' whether the XLR you plugged in is coming from a microphone or a ToneDexter?
It can't "know", but it can "assume".

At least that's been my experience with a small (now discontinued) Mackie ProDX8 bluetooth mixer. It has an alleged "auto-gain" feature. But as best I could tell, all it did was sense whether a 1/4" input (in which case it set the gain to "line level") or an XLR input (in which case it set the gain to "mic level").

When I had a vocalist using it who was very loud, it constantly clipped the (un-settable) input gain. Sure, I could control the volume with the fader, but couldn't get rid of the clipping. So I had to buy an XLR pad to put in front of the mixer.

Anyway, sounds like the Behringer requires you to set/choose the gain level yourself.
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Old 06-25-2021, 06:06 AM
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Make sure you set the DI switch on the back to "VAR," then start with the "output level" control set to the mid point or lower. The DI "Fixed" output is pretty hot! I just go through the instrument output, since the XLR input on some mixers is mic-level only.
Well, they're always complaining that the output on my K&K is way too low to be useable (which it might be, I guess), so I'll be ready to shock them.

Now that I think about it, though, it might be best to set the switch to VAR so that I have some control over what output level goes out the DI, just in case. I'll assume that rotating the volume knob all the way to the right would be the same as the fixed output level of the DI.
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Old 06-25-2021, 09:14 AM
phcorrigan phcorrigan is offline
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I'll assume that rotating the volume knob all the way to the right would be the same as the fixed output level of the DI.
I suspect that's the case. James May will likely have the real answer.
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Old 06-25-2021, 09:33 AM
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Quote:
Originally Posted by SongwriterFan View Post
...

Now that I think about it, though, it might be best to set the switch to VAR so that I have some control over what output level goes out the DI, just in case. I'll assume that rotating the volume knob all the way to the right would be the same as the fixed output level of the DI.
Good idea, and yup.
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