SoloAmp Feedback Problem

[lpa53]

SA220 SoloAmp users: Hhow do you pace your amp to avoid feedback issues? I play a K&K Pure Mini equipped steel string and a nylon string with a Baggs Anthem. Vocals are through a Shure SM58.

Both channel gains are set around 2 and with that setting, the master gain can only be around 9 o’clock or I get a huge squeal. This happens in my practice room (image) and at venues of varying configurations. I would think that with the SA’s power, I ought to be able to crank it up higher. I recently played an outdoor venue that had a lot of traffic noise to contend with and had requests to boost the volume but couldn’t without getting terrible feedback.

I’ve been placing mine about 4 feet to my right and about a foot behind. Perhaps that’s too close but I like to be able to reach the controls fairly easily while sitting on my stool.

[gfa]

Originally Posted by lpa53

...

I’ve been placing mine about 4 feet to my right and about a foot behind. Perhaps that’s too close but I like to be able to reach the controls fairly easily while sitting on my stool.

I've not used this particular cabinet, but I am confident that if you move it further away from your mic you'll increase your gain before feedback level.

[slewis]

Definitely work with your Channel 1 & 2 feedback controls on the SA, if you have not yet. I've found that to be a very effective feature. You can also point your mic a few more degrees away from the SA, and yes, you might be a little close. You have your channel inputs pretty high, but that's how I believe it's supposed to be. I also have used my body as a physical barrier between the SA and my mic. Maybe a little more behind you could help. Even the EQ for each channel might be tweaked a little. But my first sep would be messing around with those feedback controls. Keep us posted -- but I think you should have the controls necessary to make this work better for you.

[mixsit]

'Squeal, high freq? as in the mic perhaps ?

[gfirob]

I use a condenser mike and I have had to massage the placement of the SA220 to get away from mike feedback (no problem with guitar feedback). Sometimes I angle the mike and the amp slightly away from each other or move it further back (it is always much further back than you show it here). The only time I was really able to crank the volume up on that amp though (past 12:00) was when I used a graphic equalizer to address the feedback frequency. But it has never been unusable due to feedback.

[lpa53]

I have played with the feedback controls but they haven't helped. It's probably a combination of the the mic placement and the proximity of the speakers. Many places I play have a small area in which to set up so getting the amp too far away is a tough. I''d also like to be able to tweak the controls without getting up.

I wonder if designers are ever going to supply bluetooth access to the controls.

[El Conquistador]

The only time I have ever had feedback problems with the SA220 was when I switched from an EV7760A to a Heil PR35 which is a much hotter mic. The picture above is me with the EV mic. I tamed the PR 35 problem by moving the SA220 up right beside me enough so the barrel of the PR35 was slightly behind the front screen of the SA220. This eliminated the feedback, allowed me to continue to hear what the audience was hearing, and, allowed me quick access to all SA220 controls.

Win, win, win.

Steve

[lpa53]

Originally Posted by El Conquistador

The only time I have ever had feedback problems with the SA220 was when I switched from an EV7760A to a Heil PR35 which is a much hotter mic. The picture above is me with the EV mic. I tamed the PR 35 problem by moving the SA220 up right beside me enough so the barrel of the PR35 was slightly behind the front screen of the SA220. This eliminated the feedback, allowed me to continue to hear what the audience was hearing, and, allowed me quick access to all SA220 controls.

Win, win, win.

Steve

So you're saying that the layout in the picture here is one that caused problems and that you solved it by moving the amp to you right side just a bit forward of parallel with the mic? How are your channel and main gain knobs usually set and what is the max main gain setting you've been able to use?

[El Conquistador]

No, I am saying the picture with my EV767 with which I never had a feed back problem, even with the unit right behind me.

In order to defeat feedback with my PR35, I moved it up beside me.

Steve

[jseth]

I use a Bose L1 Model II system, not the Fishman unit, but I have a couple suggestions for you.

One, I ALWAYS set up with the L1 (and B1 sub) on a diagonal off my LEFT shoulder; my reasoning is to keep the main portion of the sound away from the body of my acoustic guitar as much as possible...

Secondly, loud and sudden feedback can be a result of improper gain staging... It's curious to me that you have both an active, low impedance pickup (Element) at the same gain level as you have a passive, high impedance pickup (the K&K). The two shouldn't have the same gain setting.

You also didn't say how you have your SM-58 set up on the SA330... In my considerable live performing experience, the SM58 is about the most trouble-free mic I've ever used, both for durability and "no nonsense" when it comes to feedback issues; if the mic is the source of the feedback, then I would definitely check your gain staging. Just google "gain staging" and you'll get all the info you need for whatever system you ever own... also, you can NOT have the microphone pointed directly at the SA 330... doesn't matter if you "want to" or not, just keep that microphone pointed away from those speakers!

I understand that you want to be able to reach the controls, but you may have to distance yourself a bit farther from the SA... it is simply NOT possible to produce a high level of sound pressure while sitting close to the source with an open microphone and those wonderful "resonance chambers" we call guitars....

[Gordon Currie]

In addition to other suggestions, in the original picture the SoloAmp is sitting in a corner. Acoustically that is the worst place you can put a speaker. Try moving it out of the corner and see if there is any improvement in feedback sensitivity.

When you are testing at home, next time you start getting the squeal try muting either the microphone or guitar. You need to determine which one is the (greater) offender.

[lpa53]

Thanks for all the suggestions. I've done some experimenting to see what can be done.
Before I get into the things I tried Ill note that I just noticed something odd about Channel 2, into which the SM58 usually goes. Even when no device is plugged in, at a certain point of gain, say 12 on the main and 10 on the channel, there is a wind-like sound from the speakers. This does not happen on Channel Any idea what could be the cause?
I’ll also note that I’ve been using a Cloudlifter (https://www.cloudmicrophones.com/cloudlifter-cl-1) because at one point I was having to crank the mic channel gain up to 5 to get sound without having to eat the mic. Perhaps now it’s too hot. In some of my testing, I did remove it from the chain and was able to get decent volume without eating the mic. Part of this might be that the SA instructions seemed to say to crank up the channel gain to just below getting the red light and then controlling volume with the master gain. Is this not really a rule?

The Experiment Results

The problem is definitely the mic and is only exacerbated by getting the guitar in play near the mic. The Anthem has an internal mic which might make things even worse, as might the upper bout side sound-hole on the Hoffman.

I moved the SA to my left (still gives me access to the controls and it’s out of the corner) and ahead of the mic by about 6+ inches. This allowed me to put the channel gains around 10 instead of 2, and the master gain to 12 (beyond that it still started to moan). I did get the sense that it sounded a bit more trebly than when I had it even with or slightly behind me.

Because of the differences in the two pickups, I’ve now dialed down the Anthem with its soundhole control. I’ve thought about adding feedback busters to the two guitars but the Anthem's soundhole controls and the Hoffman’s odd sized hole and the end of its neck have made fitting one difficult. And since the Hoffman has a side hole, it may not help anyway.

Anyway … for now the position seems to be giving me less problems at higher volumes but I now I have new questions:

1) What’s causing the wind sound on Channel 2?

2) Do I need the Cloudlifter? Might it actually be one cause of my problem?

3) Should I have the same pickup in both guitars? My favorite players, James Taylor, Phil Keaggy, and the late Michael Johnson, use the Baggs LB-6. And I’m no fan of relying on the in-body battery required by the Anthem.

4) Or in lieu of having the same pickup in each guitar, do I get a preamp for the K&K to get a signal closer to that from the Anthem?

[Guitaurman]

Just my opinion, but I think you are setting up your gain staging wrong. I posted this a couple of weeks ago to another guy having trouble with his SA. Try this along with getting out of the corner. With unit on, turn the master to zero and both channel gains also to zero. Talk or sing as loud as you will during performance and gradually turn up the mike's channel gain until the little red light flashes. Turn the gain back until the light just goes out. Then with the guitar channel do the same by hitting the guitar as hard as you ever will in a performance, while turning up it's channel's gain until the "clipping light" flashes and again turn it back slightly so the light doesn't flash. Then turn up the master to the needed volume. If the balance between the vocal and guitar need to be tweeked, just reduce the channel that's too strong a bit. I'll bet you'll be feedback free unless you really crank the master.

[lpa53]

Originally Posted by Guitaurman

Just my opinion, but I think you are setting up your gain staging wrong. I posted this a couple of weeks ago to another guy having trouble with his SA. Try this along with getting out of the corner. With unit on, turn the master to zero and both channel gains also to zero. Talk or sing as loud as you will during performance and gradually turn up the mike's channel gain until the little red light flashes. Turn the gain back until the light just goes out. Then with the guitar channel do the same by hitting the guitar as hard as you ever will in a performance, while turning up it's channel's gain until the "clipping light" flashes and again turn it back slightly so the light doesn't flash. Then turn up the master to the needed volume. If the balance between the vocal and guitar need to be tweeked, just reduce the channel that's too strong a bit. I'll bet you'll be feedback free unless you really crank the master.

I tried this before but did it again, with and without the Cloudlifter mic preamp.

With Cloudlifter:
Singing when kissing the mic: clip light lit at 12
Singing a few inches from mic: clip light never comes on at all

With this, and the repositioned SA, the master volume howls at 9 with Mic behind SA, though it depends a bit on its angle.

Without Cloudlifter preamp:
Clip light never goes even when kissing the mic
To get decent vocal volume, I have to have channel volume at 12 and master at 1. Anything higher yields feedback again.

But with the master volume this high, I have to keep the guitar channel gain low. I couldn't get the Anthem-equipped guitar to light the clip light. The K&K clipped around 12.

I'll still have to play around more.

And the channel 2 windy sound is still there ...

[jseth]

It sounds like something is wanky with the mic channel... should not be making any noise at all without an input source - well, maybe a bit of hiss at extra-high volume levels but that's a bout it.

Call up Fishman and ask them about it.

With an SM-58, you definitely need to be "on" the mic, but shouldn't have to have your lips against it for anything except extremely soft sounds... you should not need any sort of "extra' help to have the mic level be adequate. I don't know anything about the Cloudlifter gizmo, but all my experience with live equipment tells me that the LESS you have in the signal path, the better off you'll be. The extra equipment could actually be causing/exacerbating your trouble...

Again, I think something's wrong with that second channel on your SA... but, please, let us know how this all works out for you...