I’ve been reading some other forums lately about the Kinder AFB+. The comments are almost unanimously positive. I’ve also been reading how some amps hardly feed back at all with a mic. Interesting. I wonder if some of the builders of amps specifically designed for use with a mic are beginning to incorporate circuitry designed to minimize feedback. If it's not already being done, it sure seems like a good idea.
Imagine having a dial on your amp where you could tailor the circuitry to your specific mic.
Are the newer, boutique harp amps less prone to feedback as they are built today?
Last Edited by on Jul 24, 2012 8:51 AM
I wouldn't say the comments on AFB+ are almost unanimously positive. I do know there are people who like it, and people who don't like what it does to their tone. I also know that the more you have to set it to intervene, the more it impacts your tone.
The only amp I know of with anti-feedback circuitry built in is the HarpKing line - same guy who makes the AFB+, same circuit (or close to it.)
If your amp is underpowered you have trouble hearing it on stage, so you turn it up. You can only go so far before you have feedback. That level will be above or below the level you need depending on the noise level on stage, and the power of your amp. An AFB+ isn't going to make a 5W amp (which sounds loud as hell in your living room) audible on stage.
A big enemy of harp players (and microphones into amps in general) is the amplifier's gain. With a high gain amp, the difference in volume between two slightly different input signals is very large - so the amp tends to "leap" into the feedback zone. With a lower gain amp, the the difference in volume between two slightly different input signals is much less. Boutique harp amp makers understand this and set their amps up with much lower gain (compared to the way amps are set up for guitar) to make them more manageable. You can still drive the amp into feedback, but the approach to it is much more controllable.
@Greg: How do you know the AFB+ is the same circuitry as in the Harp King? I thought the AFB+'s components were encased in black epoxy to prevent analysis.I guess I was misinformed.
Also, isn't the anti-feedback circuit in the Harp King part of the power amp section?
Personally, I can't see ever buying an AFB+ (even assuming I cold afford one). I hate not knowing the operating principle behind a device.
Last Edited by on Jul 24, 2012 12:37 PM
I'm having a terrible time with this. Currently, I'm running a VHT Special 6 (unmodded) with one of Greg's Ultimate 57 mics. The band I'm playing with is pretty loud, so I end up having to crank my amp up pretty high to be audible, and I'm having a tough time avoiding feedback. The Kinder AFB+ has been recommended to me, but they're hard to find and expensive when you find them. At the moment, I'm doing my best with careful mic stand placement, and always turning down the volume knob on the mic when I don't have it in my hands. BTW, miking the amp into the PA just seems to compound the problem. ---------- --Dave
There are many avenues to curb feedback, the harp amp builders all have their own approaches...what "works" works. Each approach has it's own tonal benefits.
One point worth noting though is that the AFB+ and the Harpkings achieve their effects in quite a different way to each other (electronically speaking), it would be doing Kinder an injustice to suggest that the Harpking is "an amp with the pedal built in" (that wasn't Greg's intention, I know, just speaking generally rather than nit-picking his post).
There's no free ride, whether using a Harpking, an AFB+ or by going overboard on tube/speaker swaps etc, you can render an amp useless, or degrade the tone to a point to which it is unplayable. It would be more correct to say that players "get no feedback within useable parameters", rather than they get "no feedback at all"...plug into a BF Twin or a Deville, with a hot mic & AFB+ or no, you WILL get feedback at some point. (The AFB+ is a great problem solver for pick up/non Kinder amps, but as an amp becomes more tailored towards rejecting feedback, it becomes less of a necessity and more a question of preference.)
You don't really want to kill feedback, you more want to limit it to controllable levels. Harp amp builders have been incorporating these techniques (either via custom circuitry, altering existing circuits, or by careful selection of components like tubes & speakers) since the early/mid 90's. Prior to that players paid attention to mating mics & amps to best effect, as well as occasional tube subs.
I get the idea that some folks think there is a magic knob/box/amp/tube that simply lets you turn to whatever volume you want with whatever mic you want and never feedback, with no change in tone. It's not really like that. There's been a lot of good work done in making stage amps more useable & controllable in the last couple of decades...costing folks a lot of hours & effort to produce headache free solutions...the "magic feedback killer" (turn any amp to any level, with any mic & just get the same tone with no feedback) however, is still a thing of fiction/imagination. ---------- www.myspace.com/markburness
@ 7thDave - are the rest of your loud band using 5W amps too?
Most folks would use a bigger amp. If you want to keep using the VHT mic it up, or fit a line out. Fitting a line out & running a speaker emulator/load box will eliminate on stage feedback from the amp, but you will need a monitor to hear yourself...the monitor will then become your source of feedback ;-)
Jim Rossen's page on VHT mods covers fitting a line out, or a voltage divider can be incorporated into a clip-on box/enclosure, as described by Don De Stefano many years ago (may be some record of it in the harp-l archive, search for "Don box"). ---------- www.myspace.com/markburness
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Last Edited by on Jul 24, 2012 10:28 AM
@timeistight "@Greg: How do you know the AFB+ is the same circuitry as in the Harp King?"
I don't know where Greg got his info, but this is what the Kinder web site says:
"The famous "Kinder HarpMod", used for years by great entertainers around the world is now available to you in an outboard device."
This, to me anyway, infers that it's the same circuit that he uses in amps, Harp King or otherwise.
I was lucky enough to get an AFB+ and it works well in controlling feedback to a point, but it can not make the claim that it eliminates it completely. As Greg said, no matter what, if you keep turning up, at some point you will cross the feedback threshold.
However, as stated previously, the AFB+ does add something to the tone. For me, this sort of sounded kind of like a trumpet or other brass instrument. Dennis Gruenling's HarpKing 6X10 had that same kind of horn feel to it when I saw him a couple weeks ago.
Last Edited by on Jul 24, 2012 11:15 AM
@ Kingbiscuit "This, to me anyway, infers that it's the same circuit that he uses in amps, Harp King or otherwise." Trust me, it's a physical impossibility. Kinder is a clever feller, the AFB+ emulates the effects of the amp mod/design, but by different means to the amp/mod. This may be a "distinction without a difference" to many...;-)
5F6H: "are the rest of your loud band using 5W amps too?"
Heh, hardly--especially not the bass player. I realize I'm underpowered, but the VHT is what I can afford right now. Maybe I'll play around some more with miking it, or with the line-out mod as you suggest.
Greg wrote: I wouldn't say the comments on AFB+ are almost unanimously positive. I do know there are people who like it, and people who don't like what it does to their tone. I also know that the more you have to set it to intervene, the more it impacts your tone. __
We may be arguing semantics. How much the tone is effected is subjective and somewhat debatable between users of the AFB. Good tone is a matter of opinion. Here’s the bottom line for me. These puppies are hard to find “used”, whether privately, on Ebay, Craigslist, music stores or anywhere else. The lack of used AFBs seems to imply that players keep them for a reason. They perceive a benefit, regardless of the tradeoffs.
It’ very difficult (for me) to crank up my amp enough to overdrive it when I practice at home. I have to stand in a different room than where the amp is. So, in that case, the AFB may be of some benefit as well.
Last Edited by on Jul 24, 2012 11:50 AM
Noodles, what amp do you have? The reason I ask is because the AFB is the best part of $500 new. It's a useful tool & I doubt that you would regret buying one, but I'd make sure that I had an amp that was worth adding a $500 pedal to...$500 would also make John Kinder very happy if he was to mod your current amp.
I use the Kinder AFB+ as part of my regular rig when I am playing my Bassman RI. I don't use it with my Mission amp.
The Kinder pedal -- when set up to my tonal tastes -- will get me about two to three extra notches on the volume knob on the Bassman. That is a lot of volume.
The pedal does not make a horn-like tone unless you have the afb control (the right-most knob) pretty much cranked. I don't hear that with my settings at all.
Everything Greg said in comment #2 about the nature of feeback is spot on, so I won't plow any new ground there.
@7thDave - While the VHT Special 6 is a good sounding little amp, it is wholly unsuitable for what you are trying to do. It is just too small and underpowered. No amount of trickery is going to overcome the physics. You need a bigger amp.
@5F6H Noodles, what amp do you have? The reason I ask is because the AFB is the best part of $500 new. It's a useful tool & I doubt that you would regret buying one, but I'd make sure that I had an amp that was worth adding a $500 pedal to...$500 would also make John Kinder very happy if he was to mod your current amp. __ ___
I sincerely appreciate your concern over my making an expensive, unwarranted purchase. It just so happens that someone who already has one wants to work a trade for something I have, I was looking for one, and one found me. The KinderAFB+ currently lists for $359 on the Kinder site as of today. **************** Need counsel Guys, not to hijack my own thread, but something weird happened to my Champ today. I had it cranked and suddenly, she lost it. I had power but volume went to almost zip. I thought I blew something, tube, transformer, speaker, etc.
I wiggled the tubes -–no change. Then, I tapped on the rear of the speaker – just behind the magnet. SOUND ON. Happened again. Tapped again while power was on, saw some small sparks around speaker terminal (+). Sound came roaring back. It’s cut out 3 times today, but I got it back each time.
Question: Is it time for a new speaker or does it need to work out the kinks because it was in storage for 2 decades? If so, any recommendations? OR, is there something else I can do to service this original, 8-inch Oxford in my Champ?
Last Edited by on Jul 24, 2012 12:59 PM
Noodles - don't turn the amp back on until you have a new speaker, or the current speaker reconed...a shorted, or open load on the output transformer will kill your output tube in a very short time, possibly taking more parts with it.
Oh, and that Kinder Instruments site hasn't been updated for years, hopefully the pedal hasn't gone up by as much as I anticipated, best check with John first.
Noodles, when you hear that "some amps hardly feed back at all with a mic" I'd advise you to be a little skeptical. Feedback is kind of mysterious, but it obeys predictable laws of physics.
Some amps may be seem better than others, but there may be factors at play. In a person's living room all amps pretty much sound loud and bitchin'! But on stage with a loud drummer and an enthusiastic guitar player it may be a whole different story.
There are limits to how loud we can play, no matter what you do and no matter what an amp maker tells you. The most effective solution to feedback is low stage volume for everybody in the band. I know that is not always possible (Jams!) but when you do have control over the sound level you need to bring the whole band down.
I posted earlier in a separate thread about my recent experience with the Kinder. There is no question in my mind that it affects tone. Whether that is a good or bad thing depends on the listener, their taste,the settings, and I think also what amp it's being used with. I don't mind it with the Zoo. It's not good or bad, just different. I tried it once with my Cruncher and thought it was awful. I don't need it with my Avenger under any circumstances. With a Twin last night it was very useful. For me personally that's where it would have the most value, in being able to control things in situations where you're making do. I now know that in situations where I have to use whatever amp is available I can still get a decent sound and no longer have to sweat feedback too much.
Since I got the Avenger I had thought about selling my AFB+ but after last night, and considering how hard it seems they are to obtain, I'll be hanging on to it. Besides I got mine used for about $50 under the new price of $369. If they really have gone up to nearly $500 that's a surprise. For that kind of money I would have thought simply getting a bigger and/or better amp would be a better way to go. ---------- LSC
i've tried the Kinder AFB on small amps. it messes with the tone too much for my taste but perhaps there are small amps that sound okay with it. i'm pretty sure it is designed for 4/10 jobs as a rule though it works great on a modern fender deluxe (a very unfriendly amp for harp).
i mic small amps all the time with a Sennheiser 609( about $100),so i can capture the sound coming out of the speaker a little more accurately than using a line out. even so, line outs are easier to deal with when messing with the PA.
but then again, it would be more cost effective to just buy a 609 rather than install a line out. plus,there is re-sale value in microphones and they last forever. ---------- MP affordable reed replacement and repairs.
"making the world a better place, one harmonica at a time"
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Last Edited by on Jul 24, 2012 1:17 PM
If you modify a Bassman like 5F6H says you get a amp that is ridiculous loud and you don't need AFB pedals. I easily be heard 2 guitars, bass and hard banging drummer - band. I often be the loudest one... I have compared it with a Super Sonny JR and a HG50. They are not as loud as my Bassman RI LTD.
Last Edited by on Jul 24, 2012 1:23 PM
@rainman, I like the Sonic Stomp. Jason Ricci suggested I get it. It is best with the Bassman, giving a little more cut without getting shrill. The effect is subtle. I bought it on eBay for $50; thought I'd review it for the blog and sell it, but I've kept it.
I don't use much of the effect: both controls at 12 o'clock to start with and then very small tweaks.
EDITED TO ADD: I almost never use the EQ pedal. Most of the time is is only the AFB+ and the MXR delay pedal.
---------- -Rick Davis
Last Edited by on Jul 24, 2012 1:38 PM
@Free Willy; "I read the other day that Marble-amps claims they have anti-feedback built in too."
"Antifeedback" isn't any one particular circuit or mod, it is any method that allows your amp to be used with a reduced tendancy to feedback, whilst making good power & tone. Feedback resistance can be built into a circuit (like perhaps the Marble idea of it, as they cannot employ the same method exactly as a Kinder) or it an be a specific adjustment feature...or, even a specific feature adjusted/set by a tech, with a fixed value, rather than a control that the user can adjust. The way the term "anti feedback" is bandied about makes it sound like some rare element that is in limited supply and only a few folks have access to it..."Damn it, I hoped this crashed meteor would be a source of high quality anti-feedback....but it's just full of these useless diamonds!" :-)
If your amp gets to a volume comparable to other harp specific stage amps (of a similar broad design), without screaming feedback, then you have some kind of "anti-feedback" going on whether you know it & have paid for it, or not...
I have seen every kind of anti-feedback circuit in an amp that there is, they are not all the same, nor work on the same principal of amp design (even if they broadly have the same effect of reducing feedback). ---------- www.myspace.com/markburness
sometimes an EQ pedal is a great way to lower feed problems. it also can boost bass in whimpy amps, add midrange cut, and lower an annoyingly shrill high end problem.
i used to have an MXR EQ with a hardwired AC cord (they don't make stuff like they used to). it turned almost any shitty amp into something awesome.
---------- MP affordable reed replacement and repairs.
"making the world a better place, one harmonica at a time"
@ Timeistight - No, no patent, it would be virtually impossible to get anyway - with nearly 100yrs of tube technology behind us everything has been done before in some form or another.
Different designers have different philosophies based on their & their customers ideas of good tone, the methods they employ reflect that. Like different chef's recipes...imagine a chef trying to take out a patent on the tomato?! ;-) ---------- www.myspace.com/markburness
http://www.facebook.com/markburness
Last Edited by on Jul 24, 2012 2:33 PM
My Ashton viper 30 has an "anti feedback" switch, except it isn't called that. It's a tone shift, which switches a capacitor in or out of the circuit. Just happens to cut a low frequency which tends to feedback relatively early with my mic. Discovering this was an eye-opener for me in understanding the issue. 7th Dave, I feel your pain, I know those symptoms. Sometimes you can find a tiny place on stage with no feedback. Clearly you have to mic the amp for audience to hear, but for you to hear is a different prob. Could just go direct to PA, doesn't always work and then relying on a guy a long way away to provide you with onstage sound. I've had gigs where that worked really well, until I changed to an F harp, and became inaudible. My solution has been a loud amp. I know you know. It's just, I need to say its really the thing which works and if I could have the time back I would have just gone there as soon as I could. And a bassman is as good as anything; I believe they can be had secondhand pretty cheap in some places, like the US. Not here in aus, IME. Which is why I have a HotRod deville, did I mention it's made my on stage life much easier?
Here is a video of a friend playing a vintage Gibson GA-40 amp with a Kinder AFB+ pedal and an old Boss DM2 delay. I'll let you be the judge if the Kinder harms his tone.
@5F6H: Sorry to harp on this, but I still don't understand. When you said that Marble amps "cannot employ the same method exactly as a Kinder" what did you mean? Why can't they use the same exact method?
I'm not saying they do, but they could, couldn't they?
Last Edited by on Jul 24, 2012 2:57 PM
I love my Kinder AFB+. As has been said,it's not a cure all. It's pretty useless with my SJ1(22 watts). It's almost magical with a Bassman 50 head & 4X10 cab. I can crank it to insanely loud levels. It does mess with the tone somewhat if you turn the AFB knob up. It can get too dirty for my tastes. That's only at really loud levels. It sounds like a gate/compresser effect.
@ Timeistight - Sure, if they wanted to, they could. I won't go into details, it would be un-gentlemanly.
Free Willy - I struggle to see how it could have sounded much better...? You have high standards my friend ;-)
@Rick, who is your friend, sweet tone, if I had heard it blind I'd have sworn it was Gary Smith, nice slow vibrato. ---------- www.myspace.com/markburness
Mark, sorry... He's just some guy here in Denver who prefers to be anonymous. He comes to jams occasionally, and gigs very rarely. That video is from a Little Walter tribute show.
someone brought a meteor amp to a jam a few weeks back sounded to me like it had something similar to the afb+ built in. it was loud without feeding back.
@timeistight - yes, given that they were both developed by the same engineer, I assumed they are the same, or close to it, which is what I said originally. Obviously if it is built in it has at a minimum different power supply issues so the circuit will not be identical. 5F6H seems to have 1st hand knowledge that they're different - I defer to him. My T3 (total toot time) on a Harp King amp is about 3 minutes.
@7thDave re ", I'm running a VHT Special 6 (unmodded) with one of Greg's Ultimate 57 mics. The band I'm playing with is pretty loud, so I end up having to crank my amp up pretty high to be audible, and I'm having a tough time avoiding feedback"
A 5W amp only goes so loud. Period. The laws of physics tell us you need a LOT more power to get a LITTLE louder.
And I love this paragraph from 5F6h's post - he is right on the money: "I get the idea that some folks think there is a magic knob/box/amp/tube that simply lets you turn to whatever volume you want with whatever mic you want and never feedback, with no change in tone. It's not really like that. There's been a lot of good work done in making stage amps more useable & controllable in the last couple of decades...costing folks a lot of hours & effort to produce headache free solutions...the "magic feedback killer" (turn any amp to any level, with any mic & just get the same tone with no feedback) however, is still a thing of fiction/imagination."
Again - an amp of given power/speaker area only goes so loud before feedback. More power and more speaker can go louder.
i`ve been using a 1976 2x10 music man 30/65 amp since 1977.i set it at 30 watts and put the "master volume" on 7 and i can set the reg. volume up to 7 to 9 depending to the room ,this gives me a fat honk tone. i haven`t heard any one talk about using a master volume.does turning down the M.V. cut back on the gain ?... cause i can turn up to 9 on reg. volume without feedback and been doing it 36 yrs.
Here' something many of you guys tend to forget or maybe not really aware of. Remember this, the signal coming from any mic you use for harmonica has a signal strength that's at least 10 times more powerful than what comes out of an electric guitar or bass, especially a solid body and the closest to harp mic signal strength would be from a full hollow body guitar along the lines of a Gibson ES-5, ES-175 or a thinner, full hollow body guitar like an Epiphone Casino, but even those aren't remotely close to as powerful a signal coming from any mic being used for harp and that alone is gonna be a gigantic trigger of feedback, and even more so when you tight cup the mic.
Certain amps like most Fender amps past 1/2 way up will never get any louder, especially pre-CBS Fenders using audio taper pots rather than linear pots that have been used for the last 20 years and all it will do is just get dirtier.
The other things to remember is that the harder the breath force, the more likely you will feedback quicker as well.
Also remember to take into account another factor most of you guys never take into account and that's room acoustics and what materials are being used in the room you play in. ---------- Sincerely, Barbeque Bob Maglinte Boston, MA http://www.barbequebob.com CD available at http://www.cdbaby.com/cd/bbmaglinte
Bob brings up a good point. People get the volume up to 5 and think that the amp will go twice as loud if only they could turn up to 10 - but feedback gets in the way. My experience matches Bob's - in most cases once you're past 5 or 6 on the volume knob, the amp doesn't get much louder - just more distorted. (It is TRYING to get louder, but the power tubes are already clipping - so all that happens is the preamp sends a stronger signal, so the distortion gets even stronger.)
If you want to see why it takes SO much more power to get a LITTLE louder, I recommend the following article:
" To get a doubling of loudness, it is important to note that an increase of 10dB is necessary. And to reproduce that volume through our loudspeakers, note that we require ten times more power from the amplifier!"
Most feedback issues are a result of harp players running underpowered amps to loud with hot mics and not-so-great cupping.
My personal philosophy has been to use loud/cleanish amps and get the tone from cup/technique rather than the amp or mic.
The Kinder if fantastic, but really, even a noise gate would have solved most my problems. I have since sold the Kinder and have been playing with at 10 piece country rock band using pedals straight to PA. I have NO problems hearing myself ever.
People tend to get small amps that 1.) don't have much volume to begin with 2.) get cranked for either too much breakup or poorly eq'ed breakup and 3.) are trying to compete with drums and guitar amps.
Often times to a gig at a place I've never been before, I usually bring both my real '59 Bassman and my '95 Pro Junior and usually set up the Pro Junior first. Why?? Room size and room acoustics (plus I make damned sure I have players with me that I don't have to worry about volume problems because I use dynamics a lot) and the last thing I want to do is blow people out of the room by being far too loud.
Some rooms, small amps are gonna get swallowed up big time by the acoustics and size of the room can really fool you. Some larger rooms the Pro Jr is the right rig and some smaller ones the Bassman is because of the acoustics of the room.
Harp Ninja is right on the too much break up aspect of the settings because often times the first thing you lose are the dynamics and the tone control that comes from the breath control and everything is so ridiculously distorted that it's so muddled sounding that when you step about 10 feet away from the amp, everything often times sounds really god awful, and that's being ULTRA polite about it.
If you use a small amp, mic the damned thing thru the PA, but be careful with putting it thru the monitors because many sound guys too often have the monitors set too loud and that becomes feedback hell and so if I ever play a room with its own PA and sound person, I usually tell them to leave the amp OFF the monitors to avoid feedback from them.
I also have it easier because much of the time, my bass players are usually playing upright bass rather than electric, and most of those guys I never have problems with volume.
Too many players try to compete with loud volumetend to play too hard and cause many of their own problems with feedback.
Heck, the only pedals I use are a digital delay and a reverb and that's it. I stopped using a graphic equalizer over 25 years ago because most gigs really didn't need it and detracted far more than helped. ---------- Sincerely, Barbeque Bob Maglinte Boston, MA http://www.barbequebob.com CD available at http://www.cdbaby.com/cd/bbmaglinte
I play amps of all sizes vintage and non and the antifeedback is nice but will never give you the volume you need to compete. It will however allow for a slight increase and more crunch which may or may not be what you want
Best decision in the world for band playing for me was finally ditching the idea of small. Princeton is as small as I'll go for playing out.
Honestly the volume and air pushing of a bigger amp helps more.
The kinder is a tool that eases feedback issues. I don't crank it It is quite clear what it does. It is a notching filter for harmonic content. It is not transparent when it is really set to reduce feedback. It rips out big chunks of sound when it is cranked.
My experience is a bassman with the box sounds close a harpking assuming you dial it in
The octave pedal from lonewolf blues is pretty awesome and helps too. It adds harmonic content. The two together sound quite nice if you want to sound like a brass player.
Have been following so many discussions over here, I thought it's about time to join the forum.
One thing I can add concerning the discussion about the Marble amps anti-feedback design is that it is adjustable via a knob just like volume, tone etc.
It's quite effectice on my Harpwood amplifier. It increases volume to a certain degree and, depending on how much you dial in the anti-feedback, it does affect tone. Makes it a bit more dry and distorted.
Admittedly I am so new to this realm, but this discussion raises a question - why do not the singers have similar feedback problems? or do they? Their mics are open mics, the tones are in the vocal range where a lot of the harp sounds are, they have amps, monitors, PA's, they need to dominate the band, etc. etc. What's the difference? and could it apply to the harps? Just call me ignorant. That's what I am.
One reason is singers rarely fully cup the mic. Often, if a harp player goes to use a PA mic at a jam/sit in etc, you might see them tentatively cup the PA mic to see how "hot" it is & if it sets off feedback. If a player is going to cup a mic with harp all the way through a performance then the PA's owner, or sound guy, might drop the level on that particular mic to avoid feedback.
Low impedance PA mics plugged into a tube amp (without an impedance matching transformer) will usually feedback a lot less than a high impedance mic, but you may not have enough signal level to drive the amp, nor to achieve the desired tone & dynamics.
Others on this forum (hvyj springs to mind) have already stated a preference for running mics (either high impedance, or low impedance fitted with a matching transformer) in to the lower gain inputs (#2) on Fenders to make feedback more manageable. I have, in the past, used this method for vocals with a tube amp, when a supplied PA has failed. Even through a tube amp, a PA mic can be quite resilient to feedback if you don't smother it.
If you play "off the mic", through a PA, your chances of feeding back are much less. ---------- www.myspace.com/markburness
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Last Edited by on Jul 27, 2012 8:36 AM
When I practice at home sometimes with my amp I cup the mic and that seems to avoid feedback, not cause it. Leaving the mic not cupped is when feedback tends to happen. Why is this the opposite on stage? I'm guessing because cupping increases the power generated by the mic signal and the subsequent gain, and because I'm unwittingly compensating during practice.
I'm no sound reinforcement expert, but I thought of a few other differences between harp players and vocalists that may be relevant.
Vocalists rely on PA speakers to push their sound to the audience. These speakers are usually mounted to the front and sides of the band and project away from them. Harp players often rely on back-line amps for some or all of their sound reaching the audience.
Vocalists monitor themselves through dedicated monitor systems which are usually pointed at the back of their microphones. Harp players monitor their sound through the same back-line amps that they use for sound reinforcement. The speakers in these amps often wind up pointing at the front of their microphones.
The amps and speakers in PAs and monitor systems are usually over-speced and run at the low end of their useful operating range. The amps and speakers in harp amps are much lower powered and are run at the top end of their capabilities.
PAs and monitor system often use sophisticate narrow-band equalizers to "ring out" any feedback; this level of control isn't usually available to harp players.
Voices have been amplified for all sorts of public performances for, what, 80 years now? Over those years, huge amounts of money and thought have been poured into mitigating feedback and improving clarity and volume. Harp players are still pretty much using the same systems they were using fifty years ago.
Last Edited by on Jul 27, 2012 11:06 AM
Last Edited by on Jul 24, 2012 2:41 PM