SoloAmp Feedback Problem - Page 3

JackB1 · #31 02-22-2019, 09:57 AM

So is the key here to have the master low and the individual gains high?

Quote:

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.

RogerPease · #32 02-22-2019, 03:12 PM

Yes, that's basically it. This is what people mean by "gain staging".
Keep the gains as high as possible without distorting (clipping) and use the master to control the overall volume.

Then to adjust the mix, turn the too loud channel's gain down until it's balanced.
You might possibly then have to bump the master up a bit to get the overall level back where you need it.

The wide dispersion of the SA should allow you to run the overall level a bit lower than for other types of PAs.

JackB1 · #33 02-22-2019, 03:30 PM

My mic gain is always way higher than my guitars before clipping. The guitar clips at around 11 oclock and the mic can go up to around 2 oclock or more. I usually set my guitar gain first and then bring the mic gain up until it matches it. Is that OK?

Quote:

Originally Posted by RogerPease

Yes, that's basically it. This is what people mean by "gain staging".
Keep the gains as high as possible without distorting (clipping) and use the master to control the overall volume.

Then to adjust the mix, turn the too loud channel's gain down until it's balanced.
You might possibly then have to bump the master up a bit to get the overall level back where you need it.

The wide dispersion of the SA should allow you to run the overall level a bit lower than for other types of PAs.

guitaniac · #34 02-22-2019, 04:45 PM

The amount of channel gain needed will vary with the particular pickup and mic. If the input signal happens to be too hot with a particular pickup, you can push in the channel's 10db pad and reduce the input level by 10db.

Regarding feedback, the SoloAmp channels have two tools which can help with feedback: 1) The phase inversion button (which can help with feedback or make it worse - try both positions and see what happens and 2) the sweepable notch which can be used to find and notch down a specific feedback frequency.

I've often used my own SoloAmp in pretty much the same way that you have (the SoloAmp a little behind and to the side) without a problem. I reduce guitar feedback issues by using EQ tools on the guitar which can accurately cut down overly boomy frequencies without having to roll off the entire bass end. Such an EQ device will be very helpful if your pickup has a tendency to get overly boomy and feedback prone when run flat at a loud volume. Something as simple as a Boss GE-7 graphic equalizer can be much more helpful than the SoloAmp's three band EQ. (The higher the guitar amplification, the more the guitar top will interact with speaker sound and the more EQ correction you'll likely need).

A soundhole cover can also be helpful in discouraging guitar feedback.

With respect to mic feedback, the SM58 is a very commonly used mic, but its far from the most feedback resistent mic. It has a regular cardioid response pattern. This allows you to effectively sing at it from the side, but it also responds to unwanted sounds from the side. The SM58 also has a strong proximity effect which means that it gets very bassy and muddy with very close miking. To avoid feedback with an SM58, most folks will rolloff a good deal of bass and mic very close.

In my own case, I avoid mic feedback by using an Audix OM7 mic. Its designed to have minimal proximity effect with very close miking, and its hypercarioid pattern rejects sound from the side. As a result, I can run the mic at a much higher-than-typical level without needing to roll off any bass for close miking. The caveats are 1) its a "low gain design" which requires more available gain from your system (the SoloAmp easily handles that) and 2) You need to sing fairly close to the mic (Audix recommends within an inch, but a little further out can work when singing on the louder side) and you need to be on axis with the mic. It doesn't respond well to singing at it from the side.

RogerPease · #35 02-22-2019, 05:39 PM

Jack, that is ok, just fine even.

Also, +1 to everything guitaniac says.
He mentions some more tools, techniques and SA features that help with feedback.

Play on! _RP

Guitaurman · #36 02-23-2019, 02:48 PM

Quote:

Originally Posted by JackB1

So is the key here to have the master low and the individual gains high?

Not necessarily. Set the gains to where they just barely clip (the red LEDs flash when you start to clip) wile singing the loudest you will do when performing. Then turn the gain back slightly so the LEDs just stop flashing. Do the same with the guitar. That will give you the loudest and cleanest signal possible to be sent from the preamps to the power amp. Then control your stage volume with the master volume. That will vary depending on the venue not the level of the preamps gain. Other than what I just explained the gain and master levels don't really interact much.

I've been using a SA 330 for the majority of my gigs for the last year and a half set up like that and it has been flawless. The anti feedback (notch filter) has quelled any feedback I have experienced. The system is light, portable, is super easy to set up and control, and produces a great sound. It does have it's limitations as do all systems, but for small to medium sized rooms and even patios it's a great rig!

eyesore · #37 02-23-2019, 05:13 PM

i played a fairly loud bar last week with my SA220. the amp is about 6 or 7 feet away from meand about 3 feet behind. i used the idea from fishman guy to keep the Master volume low and control the gains. i still had feedback with a Seinnheiser 835.most of my gigs are low key wineries .low volume, no problem.

lpa53 · #38 03-09-2019, 08:16 PM

I've gigged several times since starting this thread and trying out many of the suggestions. I like to have to SA within arm's reach to adjust reverb settings and moving the amp just ahead of the mic has helped greatly.

I've taken the gain and master volume setting advice given here and it seems to be working. I've also taken the Cloudlifter mic preamp out of the loop and that seems to have helped, too.

I still get some odd sounds for the 220 - rushing air and some crackling - now and then (using contact cleaner hasn't helped). The sounds come and go on their own, usually lasting only a minute at the most and there seems to be no pattern or cause. Since I have no backup amp, I can't spare the time to send it in to Fishman and so will just live it for now. Everyone who hears me play with it says good things about the sound.

Regarding feedback, one thing I d wonder about is what if any affect the large soundport on the upper bout has. It opens up to, and it within 8" of the mic, and I do wonder if that's a factor in causing feedback.

eyesore · #39 03-10-2019, 04:20 PM

lpa53; do have the soloamp in front of you/ if so; can you hear it ok? i have to keep it off to the side and behind me. like you said "within arms reach."

lpa53 · #40 03-10-2019, 05:03 PM

Quote:

Originally Posted by eyesore

lpa53; do have the soloamp in front of you/ if so; can you hear it ok? i have to keep it off to the side and behind me. like you said "within arms reach."

Although I think it was designed to be placed to the side and behind so a monitor isn't needed, I've had to move it just forward of the mic to avoid feedback. It's on my right and close enough that I can still hear it and also make adjustments without getting up. I don't really fiddle much with the sound during a gig so I should probably try placing it further away and behind, but most of the places I've been playing don't have a lot of room where I set up.