Zoom A3 Volume question

[Photojeep]

Hi,
Last Sunday after Mass, I tested my Zoom A3 acoustic pedal at church as I'm think of using it as a DI and retiring the passive cheap DI I'm currently using. I'm considering this because I want to reduce/eliminate the piezo quack I'm currently experiencing with my current passive DI. (The Zoom has a piezo pickup setting that goes a long way towards minimizing this unnatural sound.)

In trying this out, I came across something very interesting:

At home, when using the Zoom with my Loudbox mini amp and using Fishman's suggested gain setting, (10 o'clock position) I can set the Zoom's master volume at around 12 o'clock and not be too loud. But when I tried this at church, I found it was terribly loud and I had to lower the setting to below 9 o'clock along with lowering the pickup input level to 9 o'clock from 12 o'clock.

My question is this: are PA systems generally louder than amps and this type of setting change is normal or am I comparing apples to oranges? I'm afraid I don't know the brand or model of our church PA and it is pre-set and locked away so I'm unlikely to be able to answer that type of question anytime soon. Hopefully this won't make my inquiry an unanswerable question but I figured it was worth a try.

I probably haven't given enough information to get the answer I'm looking for so please tell me what else you may need to know to answer my question.

Thank you in advance,
PJ

[lschwart]

In one way, all amplification systems work more or less the same way--and they are adjustable for a reason. In this case, however, because the mixer at church is locked away, you can't adjust the input gain the way you would normally, so you have to use the controls you do have access to. PA systems are of course louder than little combo amps (they have to cover a big room), but in this case what you're comparing is input gain or input sensitivity. The gain on the input channel of the mixer is set high relative to the strength of the output signal coming from your pedal. Its setting is more sensitive than it needs to be, probably, but since you can't access the controls, you have no choice but to lower the level of your output. There's no big problem with that as long as you can get a level that works with the levels of whatever's going into the other channels. You may get a little more noise than is absolutely optimal, but that's not usually a problem in a live setting.

It would be best, of course, to give someone who knows how to use a mixer access to the mixer, but I know that's not always easy given the way church music programs are organized.

Louis

[guitaniac]

Mic inputs generally have a higher level of gain on them than 1/4" input jacks. Some preamps will compensate for this (by reducing the level of the XLR output signal) and some don't. I'm guessing that the A3 doesn't since I recently had to turn the mixer channel gain way down when running the XLR output to the house mixer at a gig.

I understand that you don't have access to the house mixer (to lower the channel gain), and that its difficult to fine tune your output level when the level knob is down around 9 o'clock.

One possible solution is to use the last effect in your signal chain to lower your output level. Even if you don't want to use any additional effects, you could do something like put the graffic EQ in the signal chain, leave the EQ flat (if you're already happy with the tone) and go to page 3 and reduce the level parameter from 100 to 20, for example. You may have to experiment to find the best level to be compatible with your church mixer, but I'm guessing that 20 would be a good place to start.

PS Don't forget to push the main peddle down, when you're working with a particular effect, so the effect will be turned on (red LED on) and the output level will be reduced to the level you've set it for.

[kurth83]

So there is no mixing board, you just jack directly into a multi-channel PA?

Sounds a bit strange actually.

If you plugged into a mic jack, then yeah, that would explain it, but even my stand-alone PA speaker has a gain control for its inputs.

I generally prefer to send a strong signal to the board and let them compensate downwards, that reduces all kinds of noise problems, like hum and whatnot.

[Photojeep]

Thank you all very much!

Yes, this sound system has had a very troubled history from when the church was first built. It seemed that while lots of money went into the system components, not one cent was spent on anyone to work it. As a result, there has been a long and distinguished list of people who claimed to know what to do- Starting with a young man who, when not participating as an altar-server, would run sound for various Masses. Apparently he'd "worked with systems like these before" but rather than adjusting any volume sliders, he rode the gain inputs. Terrible feedback was the normal order of the day for a very long time.

After too many years of this type of malfeasance, the church, probably out of desperation, went to a set-it-and-leave-it system that is under lock and key. As a result, all of the various choir members and instrumentalists have all had to adjust ourselves to the system's preset input levels. No one has access to the system. There is no board that I've ever seen, but rather some locked panels that resemble circuit breaker boxes like in one's basement.

I'd just become accustomed to it since I had always used a standard DI box but lately have been hearing the dreaded piezo quack and decided to try out my Zoom A3 pedal to tame that. Once I tried it however, that's when I noticed the incredible volume difference between a "normal" passive DI box and the Zoom.

And if it helps: One interesting thing to note is that in addition to the Alvarez acoustic electric that I currently play, which is equipped with the standard 1/4 inch jack, I used to use an Ibanez that is equipped with both 1/4 and XLR output jacks. The 1/4 jack on the guitar always acted "normal" in that I plug that into my DI, I have a lot of volume adjustment available from my guitar. I normally set it around 10 - 11 o'clock. However, using the XLR jack means I find I need to set it at ALMOST 7 o'clock - and the 6 o'clock position is OFF.

Thank you all again and I will be looking into some of your suggestions guitaniac and see if that will help. Of course if any one else had something to contribute, I'm all ears.

Best to all,
PJ

[RockerDuck]

I have one mixer, A&H Zed10fx, that has 30 db mic inputs. My other mixer, Behringer 1204usbfx, has 130 db mic input. Therefore, mixers are built different for mic input amplifiers. I used my A3 with my Behringer mixer and over amped it to the point of clipping. Not so with the Zed10fx.
Do not use the A3's Xlr out, but use the 1/4 out with a passive dI. That should work.

[kurth83]

Well that explains it, I guess if it works then all is well.

[Photojeep]

Originally Posted by RockerDuck

I have one mixer, A&H Zed10fx, that has 30 db mic inputs. My other mixer, Behringer 1204usbfx, has 130 db mic input. Therefore, mixers are built different for mic input amplifiers. I used my A3 with my Behringer mixer and over amped it to the point of clipping. Not so with the Zed10fx.
Do not use the A3's Xlr out, but use the 1/4 out with a passive dI. That should work.

Mr. Duck, you nailed it! When I mentioned earlier that my loudbox mini I'd forgotten that I had NOT been using the XLR out but rather the 1/4 out with a passive DI. Boy, do I feel stupid...

Well, I've said it before and I'll say it again. This forum ROCKS!

Thank you again,
PJ

[guitaniac]

Originally Posted by Photojeep

Mr. Duck, you nailed it! When I mentioned earlier that my loudbox mini I'd forgotten that I had NOT been using the XLR out but rather the 1/4 out with a passive DI. Boy, do I feel stupid...

Well, I've said it before and I'll say it again. This forum ROCKS!

Thank you again,
PJ

If your church's DI boxes don't drop the signal level as much as you need (-3db is typical for a passive DI box, I've read), you could get one with an attenuator switch or a PAD input button like the one in this Radial DI box I've linked to. (This particular PAD drops the signal level by 15db.)

http://www.sweetwater.com/store/detail/ProD


Or you could just use one of the A3's virtual effects to lower the signal level, as I suggested. It would save you the need for a DI box and an extra cable.

The ideal solution would be to lower the gain on your mixer channel, but that's not an option, apparently. That channel's gain is "set in stone" to accommodate a mic level signal, so you'll just have to send it a mic level signal (in a manner which will allow your A3's master level control to be used for making fine adjustments).

[Photojeep]

Guitaniac,
So this PAD basically reduces the level of the incoming signal by 15db? Sort of like an extra valve on a water line? I may have to check that out.

Thank you!
PJ

[guitaniac]

Originally Posted by Photojeep

Guitaniac,
So this PAD basically reduces the level of the incoming signal by 15db? Sort of like an extra valve on a water line? I may have to check that out.

Thank you!
PJ

Oops, the link doesn't take us to the page which I took it from. I was looking at the Radial ProDI. In any event, you push in the button described as "-15db PAD" and it reduces the signal going into the DI by 15db.

You'll also find these PAD buttons on inexpensive mixers which don't have a gain control on each input channel. (The channel has a level control, but the gain is fixed.) They are used to prevent an overly hot signal from over-driving the channel.

Some DI's have an attenuator switch which serves the same purpose as a PAD. I tried to link to a photo of one but had the same problem as I had before. Sorry. Hopefully, this page will link to a variety of passive DI pics, some of which have PAD buttons or attenuator switches.

https://www.google.com/search?q=Pass...LH8B0MWtTEM%3A

[lschwart]

Originally Posted by guitaniac

If your church's DI boxes don't drop the signal level as much as you need (-3db is typical for a passive DI box, I've read), you could get one with an attenuator switch or a PAD input button like the one in this Radial DI box I've linked to. (This particular PAD drops the signal level by 15db.)

http://www.sweetwater.com/store/detail/ProD


Or you could just use one of the A3's virtual effects to lower the signal level, as I suggested. It would save you the need for a DI box and an extra cable.

The ideal solution would be to lower the gain on your mixer channel, but that's not an option, apparently. That channel's gain is "set in stone" to accommodate a mic level signal, so you'll just have to send it a mic level signal (in a manner which will allow your A3's master level control to be used for making fine adjustments).

I agree that it's better--in this less than ideal situation--to lower the output level of the XLR out on the A3 than to mess with adding a pad or a DI with pad to the unbalanced line out.

Louis

[lschwart]

Originally Posted by RockerDuck

I have one mixer, A&H Zed10fx, that has 30 db mic inputs. My other mixer, Behringer 1204usbfx, has 130 db mic input. Therefore, mixers are built different for mic input amplifiers. I used my A3 with my Behringer mixer and over amped it to the point of clipping. Not so with the Zed10fx.
Do not use the A3's Xlr out, but use the 1/4 out with a passive dI. That should work.

Does that Behringer mixer really have 130 dbs of gain available on its mic inputs? Or am I misunderstanding what you're describing here? The mic inputs on the ZED10fx go up to 60 dbs (40 for the line inputs). Again, I may be misunderstanding.

Louis

[Photojeep]

Quick update:
Yesterday I used my Zoom A3 at church and plugged it directly into my existing DI as was suggested above and I was very impressed!

My original intentions were to 1. Remove my current DI; 2. minimize the quack.

Since I cannot get to the board to adjust signal input levels, I just inserted my Zoom into the signal path between guitar and DI. Boy what a difference! At least I now have a guitar sound that is much more acoustic-guitar-sounding so at least goal #2 has been accomplished.

I'm not sure if I will investigate the PAD DI option since I'm so happy with my newly improved sound and my current DI still works like a champ but I am thinking about adding the EQ effect with the output level lowered to eliminate the DI completely.

Thank you all again,
PJ

[guitaniac]

Thanks for the follow-up, PJ. I was wondering how you had addressed your level problem.

Are you saying that your DI lowered the signal level enough that you could put your A3's master level knob in a more easily adjustable position (as in closer to 12 o'clock than 9 o'clock)? If so, its fortunate that you already have a DI that can do that job. (There's no need for a DI with a PAD or attenuator switch.)

With respect to a fix which will allow you to eliminate the DI and the extra instrument cable, in an emergency you could always do the "quick and dirty" thing of lowering your input signal. That should work passably well (to get your master knob position where you want it) though its usually recommended that the input signal be set just below clipping for the best efficiency of your device. Using one of the virtual EQs (graphic or parametric) to lower the output level would work better, I suspect.

Using one of the EQ devices would also give you the opportunity to experiment with tweaking the EQ, if you happen to be so inclined.