Best mini cardioid condenser for DB
 

I just picked up an Acoustic Image Coda R series III a couple of days ago and have already gigged twice with it. It's a fantastic piece of gear, IMO. I used it outdoors on the 4th combined with my Ampeg PB212H cab which boosts it from 400W to 500W and I was able to run it half Master and half gain on the channel. It was quite loud with no feedback. The pick-up I used was the K&K bassmax with no pre-amp. I was able to run the EQ flat.

I suppose that pick-up is perhaps as good as any;- I've never heard a pick-up that was substantially better, just slightly different in one way or another. Still, I want something that amplifies the acoustic sound of my bass now that I have an amplifier that will easily allow microphones.

So I am going to tread into that quagmire of miniature condenser microphones. The Acoustic Image has phantom power, so it makes it possible to use those mic systems that either will work without a separate pre-amp or have the pre-amp powered by the phantom power so it doesn't need a battery (I am particularly averse to battery powered gear). Also, I don't need a blender because the Coda has 2 channels and I can blend on the amp very easily, so blenders aren't a necessary part of my strategy.

I didn't expect to find so many mics that could be used this way, so I need some help figuring out which is most useful. The ones I have found that qualify for use in this fashion are very diverse in price, but generally have fairly similar specs, although some appear to have more low end sensitivity than others. I'm willing to spend more money if it really makes a difference in sound quality. Keep in mind I use a 5-string DB and need some sensitivity down to 30 Hz. Most of the ones here will accomplish that by proximity effect if no other way, and the cheapest option seems to have the most low end down to even 10Hz, although I see that much low frequency sensitivity as a potential problem.

Below are some that I am considering and I welcome suggestions on the pros and cons of these, or other ones I might have missed, from anyone who has experience with miniature condensers that mount on the instrument. I'm interested most in getting a much, much better sound than any pickup produces without getting feedback at a small venue volume level. I think I listed them in descending price order or close to that. The top one sells on the web for around $1500, and the bottom one for a little more than $100. Except for the AKG, they are cardioid pattern. I'm not sure how to describe the AKG 411 pattern since it is a different type of design. Anyway, post your experiences positive or negative with any of these or others that are similar in function and design.

DPA 4021 (pre is built into the capsule, but amazingly small despite that)

AMT SB25 (pre is box that can run on phantom)

SD Systems LCM 100 XLR (pre is box that can run on phantom)

Audio Technica ATM 350 (pre is box that can run on phantom)

Shure Beta 98 H/C (pre is box that can run on phantom)

K&K Golden Bullet mic XLR (pre is box that can run on phantom)

Audio Technica Pro 35 (pre is box that can run on phantom)

AKG C 411 (this is a surface mount type contact condenser mic, it is not a piezo) (pre is box that can run on phantom)

AMT S25b
 

I've been using an AMT S25B with a tailpiece mount for a couple of years now and have no complaints with this setup. I currently mix it with a Fishman Full Circle and usually have a mix of roughly 50-50 or maybe 60-40 (AMT to FC). By using this mix I can get plenty of volume for most jobs out of my Series III Coda and still sound "acoustic". On quiet jobs, I sometimes just use the mic alone. I've never had a problem picking up drums or other instruments with the AMT. I position the mic right on the center seam just below the end of the fingerboard. I use a pair of women's hair ties attached to the bridge legs to center the goose-neck and minimize movement of the mic head. With this setup, I have no problem keeping the mic positioned 1/8" or closer to the top. I did not like the AMT stock mounting system that clamps to the bouts. With that setup, you have to attach it for the job and then unattach it when you put on your case. A real pain! I designed the tailpiece mount so that the cord is detachable, but I leave the mic on my bass at all times. I keep the black box (preamp) attached to the top of my Coda with Velcro. I once did an A-B in a recording studio against a vintage Neumann U67. The Neumann did sound better, but the (very experienced) engineer said he thought that I could take the AMT into any studio in the country and wouldn't have to apologize for it.

Audix ADX20i. The regular model hasa cardoid pattern, but I prefer the hypercardoid model, which is less prone to feedback.
(Link to pic)

Well, this thread didn't take off probably because I first posted it in the wrong place and then I reposted it and it said moved, and well, it was confusing I think. So after several weeks, and probably the day before or maybe even the hour before Bob Branstetter posted about the AMT, I ordered a mini-condenser off of the list after I found a supplier. But don't let that stop anyone from posting about any mic on or off the list. I will post again about the mic I ordered as soon as the midget arrives, hopefully in a few days. Thanks Bob and Jonas for contributing. Any mini-condenser favorites that you have and care to talk about, I am all ears....

Audio Technica Pro 35
 

Just played a gig with Patricia Barber at the Green Mill in Chicago and the club has recently purchased one of these as a "house" bass mic. While I couldn't hear it from the bandstand (it was going solely through the PA mains and I was also using a pickup and amp) the very talented soundman told me he is happy with it.

I played Bob Branstetter's bass at a jam session last weekend and thought the sound was very nice. Due to the proximity to the drummer's ride cymbal the mix was less mike and more FC, but he had a really warm, natural tone with plenty of wood and air. The tailpiece mount for the AMT is an install it and forget about it thing. If I had an amp that would take it, and the cash, I would spring for it myself.

OK, I've had this thing long enough now to comment and I've used it in the worst room (acoustically) that I normally gig in as well as in a few rehearsal situations. I bit the bullet, went the distance, maxed it out as they say, and forked over for the DPA 4021 and it's fancy little shock mount bracket. The worst thing is that I have no direct basis for comparison, except something like a dynamic mic stuck behind the TP or perhaps one of my cheap condensers that needs to be on a boom stand. I almost feel like I should get that Audix, Audio-Technica, or something a lot less expensive to see how much difference in sound there really is so I can confirm what I paid for. I suppose I could A-B it with my MXL 991 on a mic stand just to hear something else, but I am sure these would be worlds apart.

Some of its' "quality" is less tangible and probably not something appreciated on a A-B listening test such as the fine callibration that makes this one of the microphones that is good enough to use for scientific sound measurement purposes (of course when do most players need that?). Then there is the material and quality of construction of the the unit. Even though the wire is very thin, it does not feel flimsy. And the housing has a "heft" for its' size that confirms that it is mostly metal and probably no plastic anywhere in the capsule. And it has better humidity resistance and durability as well as a tolerance for higher sound pressure levels and the nearest to a flat response of anything I've heard. So there might be some quality in the package that is pure durability, and some that is just tighter adherence to performance specifications. The fact that the pre-amp is internal to the housing of such a small capsule would appear to be the main premium feature that separates this from other fine mics like the AMT.

I was looking for a tiny mic I could just plug into a phantom power source and not need an intermediary pre-amp box. I think the DPA is very rare in this respect, if not a bit precious because of it. It really sounds great to my ears. My bass only louder? I don't know if that can be used to describe what comes from a mic. But it is the first time that I felt I was really hearing my instrument amplified well.

Feedback rejection is better than I expected, also. I can stand right in front of my AI combo and at the "just before feedback point", it is just as clean there as behind or off to the side. The worst position for feedback seems to be at about 45 degrees and to one side. On the safe side, I am able to run the channel at about 9:00 o'clock with the master at 12:00 o'clock. If I run the Ampeg 212H cab as extension, a bit out in front of my position, I can use the same gain settings and be much louder and still, no feedback. I am using the notch on the AI, and its' position is room dependent. It is loud enough this way that I don't need to blend in the piezo in most rooms I gig in. I'm thinking a bit of both might actually cut through the mix best so I still have some experimentation to do.

Nothing is perfect of course;- and with the DPA it is a small issue with the very precious mounting gadget. It has a clamp for the afterlength that uses a foam strip sandwich that could be a bit beefier. The foam compresses too easily and the clamp is then subject to slipping. Other than that, the clamp works great and is a pretty finely machined and designed piece of work. One twist loosens the whole mechanism and one twist tightens it. It reminds me of the way the accessories for my Rolleiflex cameras were made;- really hard and precisely machined fine steel. It looks flimsy and under-engineered, but in practice, the metal parts are truly pared down to the minimum structure for a mounting clamp and once it is tightened into place, it is pretty solid. It just needs stiffer foam in the clamp part. I'll probably alter that and put thin cork in place of the foam. This is a bit frustrating because at the price of this mounting rig, DPA should have paid more attention to this. Still, it's the only flaw I could find in an otherwise really nicely made device.

I also want to hear how it records from this close in. Conventional wisdom is that recording is best from some point out in the room, but if close micining can sound good this might be the mic that does it. Live, it sounds so much nicer than a piezo that I will only use the piezo when volume is a big issue. Right now I am just enthralled with the smooth and even response.

David - Could you post a photo of the shock mount or a link to a photo. I tried to find one on the net and didn't see anything that looked bass mountable. The specs look good. If it is anything like the AMT, you should experiment locating the mic. What sounds good in your livingroom may not sound good on the job. For me and several others the best sounding spot that produced maximum, usable output was well removed from the ff holes area (at the end of the fingerboard, right on the center seam and almost touching the top). Let us know how it works on jobs with drummers and noise. Since you have an AI Coda, adjusting the mix is pretty easy. The only bad thing is when you have to dial up the piezo, you hear how bad it really sounds compared to the mic.;)

Are you able to leave the mic on the bass more or less permanently attached? That was my biggest objection to the AMT mic system. After about a half dozen jobs I knew that I had to design something that would eliminate the set up and tearing down on every job. That got old real fast.

I'll get a photo of it up and how I mount it soon. There's a not so good photo of it here (look in the appications / bass link), but it shows it pointing off toward the f hole and that is not how I am positioning it. The mount allows a good deal of flexibility and swivel and I have it almost dead center just under the bridge with the mount crossing the afterlengths of the A and D strings.

I haven't had time to mess with it yet but there is a separate little wire doo-hickey that has a cork screw at one end and it came with the microphone and was not an accessory extra. Looking at that thing, I think it might be possible to get it up under the Fingerboard extended down toward the bridge. I'm thinking screw the cork screw end into a carefully shaped wine cork, glue (hide glue) the wine cork to the underside of the FB and then I have a mount in that position. The position just under the center of the bridge is working pretty well, but I've seen the position between bridge and fingerboard used by many professionals and I'd like to try that.

It is possible to leave the whole shooting match clamped onto the afterlengths, coil the cord and drop it into the quiver, and pack. The only problem there is that too soft foam that gets compressed and then slides down the strings. I think if I remove the mount after every use, the foam is not such a problem, but it definitely compresses too quickly for leaving it in place. I might replace the foam with cork this afternoon.

Photos of DPA 4021 mount
 

Feedback?
 

Nice looking pickup/mic.. How is the feedback as compared to something like an Underwood or Shadow pickup when played at high volumes or near the amp?

Ken, the only direct comparison I can make is to my K&K bassmax. Using the Acoustic Image Coda Combo (down-firing 10, forward 5 and tweeter), I can run the K&K at 12:00 o'clock on both the master and the channel gain with no danger of feedback in most situations. I've been able to use the DPA mic alone in a couple of situations where I have previously used the K&K alone, so direct comparison in those rooms is possible. In those rooms I was able to use the DPA with the channel gain at the 9:00 o'clock position with the master at 12:00 o'clock, so the gain is considerably reduced. Of course the "loudness" that is produced is not necessarily the same relation as the channel gain, but it is a pretty good indicator.

To compensate, I used my Ampeg PB 212H cab as an extension on the AI. This increases the efficiency of the head (400W to 500W) and more than doubles the speaker area, so it makes up the difference quite well. I'm not sure why, but adding the extension cab did not decrease the channel gain before feedback. I placed that cab about 90 degrees to my DB off to my right and just slightly forward. The AI was behind me and slightly left. These were pretty close quarters. I did use the notch filter on the AI with the DPA mic. Position of the notch is definitely room dependent. With a concrete floor the notch is at the top of the high frequency range while on a carpeted hollow wooden stage, it was rolled all the way to the bottom end. Also in one room it was better with the bass boosted just slightly on the amp. The other room was OK with flat EQ (the wooden stage).

This approach works really well in a small room and of course sounds much better than the K&K. I was actually very surprised at how good the feedback rejection is on the DPA. It's definitely the best of any cardioid condenser I've tried for anything. It rivals some dynamic CAD vocal mics I have that are as near to feedback proof as any mics I've seen. Unfortunately I haven't tried any of the other miniature condensers.

It seems if it is going to feed back, the position is not too important except if the AI is 45 degrees and in back of the bass. In front, 90 degrees to the side or even directly behind the bass is fine. I was able to move around just as I normally would and didn't feel like a slight side step would set the thing howling, but there is a fine edge to the level, and I have to stay under it. Just a tick beyond that 9:00 o'clock position and all is lost. First it gets that really boomy uncontrollable response and just beyond that, it howls at whatever mid frequency the room supports.

One day we'll have to gather up a bunch of these other mics and test them side by side. I don't know many other players using mics locally. Chris Wood is from here and I see his brother Oliver pretty regularly and we are good friends and I know Chris uses a tiny mic mixed with a Fishman FC. I think it must be the Crown mic that is sometimes supplied with those. He has it mounted in a similar position to what Bob B. describes. On stage he is playing mostly with the Full Circle cranked up. Maybe next time I see those fellows I can egg him into a comparison some way. He's a bit famous you know, but pretty down to earth.

I really do like the fact that the DPA mic as you see it is all there is to it;- no pre-amp or battery box to connect in between. Of course it means you must have a phantom powered system but these days that is almost every house board.

Ken - most of us who are using mics with bass amps (as opposed to using the house PA) use the mic mixed with a pickup. I've used an AMT S25B mic and a Fishman Full Circle for about 2 years now. I've never, ever, had any pickup that I thought truly sounds anything like what the bass sounds like when it is recorded with a mic in the studio. By mixing the mic with the pickup, I am able to get a good "acoustic" sound in most situations Feedback will always be a problem with open mics that are near a speaker. The better mics for bass reject feedback and picking up noise like drums and cymbals, but if the volume is loud enough, they will all feedback. By mixing the mic and pickup, you can vary the relative amounts of mic and pickup according to the job you are on. One relatively quiet trio jobs, I mix in more mic and less or no pickup. When high volume is required the mic gets turned down and the pickup goes up. Even a little mic in the mix adds a great deal to the overall sound at higher volume.

The DPA mics are a very nice 'luxurious' mic to use on an instrument.

Known for very accurate and detailed reproduction.

Usually used for recording fine instruments accurately. To use these in a live setting to amplify is a VERY nice luxury.

Looks like a great set-up.

Huh?
 

Does it feed back at loud volumes? yes or no? I bet you can't post a single word or sentence, can you?

Mic alone...
 

Bob, let's say I am playing with a Trio in a small restaurant and don't need a lot of volume. Would this Mic pictured above work as well as my old AKG160E wrapped in foam in the Bridge? The AKG plugs right into my Amp and sounds great. Used it with the Gilkes on night with only a tiny bit of volume.

That would be a little hard to answer since I have not used that particular microphone. Years ago, I used the AKG's and other mics wrapped in foam stuffed in the bridge. At the time, I thought they sounded good. Howerver, IMO the more modern shock mounted mics have a more natural sound and produce more usable volume.

YES!!!!! :D

Luxury? Luxury in one area is afforded by forgoing luxury in general I suppose. I admit that for the most part I favor premium equipment and have really good bass gear. That said, there is just no end to the list of things that I never have owned or ever want to own that many take for granted as necessities. This is business equipment. It is a long term investment. It is a high ACRS deduction. So I can rationalize it.

I used the DPA again live yesterday evening and it did fine, although that space is very cramped and I did have to reduce the channel gain just a touch. It is such a noticeable difference between a mic and a piezo that I will use it whenever I can get away with it. For the gigs I currently have, it will get a lot of use.

DPA update: I used the 4021 mic this weekend on a very loud, very live outdoor stage with great success. This is the first time I was able to use it combined with the K&K bassmax piezo through separate channels of the Acoustic Image Coda. The strategy was a little different than I envisioned originally, but I adapted it to the house equipment instead of using my own extension. The problem was impedance matching because there were no 4 ohm speakers available to run as extensions. So instead I ran from the effects send of the DPA channel to the house bass amp, an SWR combo with 15" reflex that was also powering a 4x10 GK cab. The combined output of both channels on the AI went directly to the board post EQ. So the stage sound was mostly mic, the feed to the PA was more piezo. The result was a really clear sound with a lot of punch. I used the notch on both channels to control the most likely feedback frequency. The sound was as loud and feedback free and carried really well considering the audience was spread out over a few acres. With the AI weighing in at 20 lbs., the heaviest thing I had to cart to the stage was my bass.

I did beef up the DPA mount clamp with strips of cork and that worked really well. This whole system has turned out to be extremely versatile and sounds fantastic live either pizzacato or bowed. I got a lot of very positive complements on the sound of the gear from other musicians and even from the sound technicians.

Hi Bob,

My AMT should be arriving in the mail very soon, and I would love to know exactly how you removed it from the standard mounting systems it comes with and perhaps some more about how you attached it to your Double Bass. Is it pretty easy? Maybe this will all be self-evident when I receive the mic. In any case, your experience would be much appreciated.

The mount I'm using now is the second design I've done. I made the first one from spruce. It was OK, but I really wanted one that I could adjust the angle of the mic coming out of the tailpiece. My current design was made from a short length of 2" Aluminum angle stock. The mic tube is attached with the same small plastic pipe clamps that are used to attach the jack on Gage Realist pickups. They are available in most any hardware store.

Before you start, keep in mind that this modification will void your AMT warranty. It's a good idea to use the mic a while with the factory clamp so that you can be absolutely sure that you have found the best location for the mic head. In my case that spot was located directly under the end of the fingerboard and on the center seam. I keep the mic less than 1/8" from the surface. While this may seem to be an unlikely place for the mic, it enables me to get a great sound and much more usable volume before getting into feedback. I've found that the area around the ff holes is one of the worst places for the mic as it gets a boomy sound and is more prone to feedback. This may not be the best spot for you, so experiment on jobs since it will always sound great in your living room.

Removing the AMT body clamp from the tube and goose-neck can be a challenge. Thanks to Marty Paglione (the designer of the mic) at AMT, I know that you must heat all of the tiny set screws with an alcohol lamp before removing them. If they are not well heated, the threads may strip when you try to remove them because they are installed with Loctite so they won't vibrate loose. As I remember, there are 3 different size set screws. I had to go to a machine supply shop to find the smallest Allen wrench since it is smaller than any of the "standard" sizes. I can look up the sizes for you if you need to know. Once the set screws are removed, you can slide off the clamp portion. If you aren't real good a soldering small components, having a friend who is good at it will make the job a lot easier. You must cut the cable coming out of the tube housing and install a Switchcraft EN3 plug on the mount if you wish to keep the wiring to the preamp the same as it is stock. Of course you will need a EN3 jack for the cord that you cut off. They are available from several mail order electronic supply houses. You could substitute a Mini XLR plug and jack for the EN3. That will do the same job and are probably be a little more sturdy than the plastic EN3 fittings.

I attached the adaptor to the back side of my tailpiece with cap screws (Allen head). By using an Allen Wrench, I can loosen or tighten the screws (after initial installation) without removing the tailpiece again. I tapped the threads into the tailpiece so that I could partially loosen them to remove the mic mount and then reattach it as many times as I might need in the future. As it turned out, it has been permanently attached to the tailpiece for the last two years.

I'm sure there are other things that I left out, but this should give you a pretty good idea of what my mount is all about. Feel free to PM me if you have any specific questions. FWIW, I also wrote about the mount over on the TalkBass forum.

Unusual Observation?
 

At a recent rehearsal using the DPA 4021 with the AI Coda, I observed a curious behavior concerning feedback or the lack thereof. I noted earlier that I could run the channel (notch filter on) with the gain at the 9:00 o'clock position and the master at 12:00 without feedback. What I observed at a recent rehearsal (concrete floor) and confirmed at a a gig today (carpeted plywood) is that I can boost the master gain well beyond 12:00 o'clock and still not get feedback while attempting to increase the channel gain beyond the 9:00 o'clock position results in immediate feedback.

This seems odd to me, but in any case, boosting the master now allows me to get very loud with the mic and still no hint of feedback or boomy resonance. Odd, but a welcome discovery. I'm guessing the behavior is the same with other mics as well? Has anyone else experienced this?

I've never tried running mine that way since I get plenty of volume with my S25B by leaving the master at "12 O'clock" and I frequently have the input level up around 11. Of course knob positions aren't really a good measure of the actual (db) output. The sensitivity of the input device (mic or pickup) can make all the difference in the world.

The AI Series III Coda manual says (on pg. 3):

"The input level controls the level of the signal at the input stage of the preamp. The master volume controls the output of the preamp (at the input of the power amp). Set the master control at "12 O'clock" and the input level at zero. The input level should then be used to control the overall output of the unit. The two controls are provided to allow independent control of the "house" volume and "stage" volume when the unit is used as a stage monitor with a connection to a house PA."

It would be interesting to see how your system responds without the notch filter on. I would assume that the notch filter would be on the preamp.

Mics..
 

I played last Saturday night in a club and was the 3rd gig I used my old 1970s AKG Mic wrapped in foam in the bridge legs. Would one of these new thingys you guys are talking about be better in any way or are they just smaller? I am asking because I am a bit of an old schooler and have not tried anything new other than the Shadow Underwood copy which I also like. I use that usually but in a small club or recording with an expensive English or Italian Bass that the Bridge doesn't want to be altered I have just used the Mic where volume wasn't an issue.

To Bob B.'s:

Those instructions are why I had not previously tried to go beyond 12:00 on the master. In fact I can't really explain why I finally decided to push it and see what happened, just a sudden impulse I guess. The notch is definitely channel specific so it is applied to the pre-amp gain. The phase reversal function is what it is doing that is possibly the most important. I might call Rick Jones and see if he can explain the behavior. Anyway I'm kind of happy to discover that I can push it up a bit more.

Responding to Ken:

If we are getting better results from smaller mics, it is probably more because we are using them with AI amps. The notch filter and phase reversal features are critical feedback reduction measures that make a real difference. The only thing that is better about a smaller mic is that it can be mounted on the bass closer the wood, very close in fact. This gives the mic a stronger input and the large area of the bass in close proximity helps sheild the mic. Other than that, there is no reason I can think of that a smaller mic should or does work better. If you can get the big one right up on the bass, I would think it would be very similar with an AI amp.

It still feeds back before the piezo!! ;)

ok.. ok..but...
 

Ok but, I only use the AKG in a studio setting or on a smallish Trio or Duo gig where I just need a little more volume for audibility and pitch. I think the Basses I use in those settings sound fine acoustically but they are used to hearing more bass these days. The first time I did this was at a trio gig and Arnold had just finished the restoration on my Gilkes. He told me the Bass needed to be played a lot to break in again. I told him I had a trio gig and needed to cut the Bridge tabs for the Pickup. "You're gonna cut the Bridge I made for the Gilkes?" he screamed at me..lol.. "Ok ok.. I'll use a Mic".. I said to him. So, that's how I got into using the Mic again, out of fear..lol. It was in a bag of stuff in my basement that has been stored away since I retired from Playing in the late '70s. It still worked and sounds great every time I use it. In one place I play, they have an Amp there so I just use whatever Amp is convenient.

I agree with some of this and have a different slant on the rest. I have the same AI Coda combo amp that David has. I think at least part of the reason that we get more mic volume before feedback is the down firing design of the AI combo amps. I only recently started using the notch filter and was still able to get plenty of volume (without the notch) in most situations without feedback.

One difference with the AMT S25B mic is that it was designed and has a preamp that is designed just for doublebass, and it has a built-in shock mount for the mic head. That has to be one of the reasons it works well. The goose neck on the AMT mic allows me to have the mic just barely not touching the top, so as David said it gets more of the wood sound. As I mentioned in a previous post, I used mics wrapped in foam rubber and stuffed in the bridge years ago myself. However, anytime you do that, you have to be deadening the top and bridge vibrations a little (at least).

deadening the top..??
 

Well Bob, anything that touches the Bass including a rag under the tailpiece, a bow quiver or any other mounted pickup can deaden something somehow. Every orchestra player that comes here to try out a Bass pulls out the rag I keep under the TP (for wiping the strings) as they claim it dampens the sound.

By the way, doesn't the bass touch our body when we play? Are we deadening it as well? If that is true, I deaden it now more so that I did 30 years ago..lol

The 3 Basses I have used the Mic on recently were as follows; The Gilkes with a Trio, the Loveri in the Studio and the Riccardi Storioni with a Duo. I don't think any tone loss was noticeable on those Basses as the have a bit of sound to spare..

That's true to a certain extent, but it is the Top that generates most of sound. I don't touch the top when I'm playing - do you? I don't know if you are deaden it more today than you did 30 years ago, but it's pretty certain that your ears aren't as good as they were 30 years ago. I know mine aren't, so I can't afford to throw away any sound when there is a way to prevent it. :rolleyes:

30 yrs ago..
 

I agree with you on the Top thing to a point but when listening to Basses I often hear more sound on some of them from the Back than from the Top standing close to the Bass.

I think that some Basses can be dampened more easily as they may have less sound to put out to begin with. On the other hand, many of the Basses I have are so powerful in comparison, I rarely hear the other Basses around me in the section. In that case, even if objects do dampen the Bass, it is no great loss to be noticed.

I suppose it might be worth mentioning that since I have improved the amplification method for my double bass, I think the only use for something like a EUB at this point would be for airline travel. I suppose it may take a while to confirm that, perhaps a few more outdoor shows. I have another one coming up at the end of the month. And even the best amp and mic combination is a good deal less $$ than a Clevinger and I get to use the same DB.

I have to agree with Ken as far as a great deal of sound coming from the back of the bass. In a standing situation I can really feel the back of the bass reverberating rather strongly while I play. The effect I observed and described in another thread which involves "early room reflections" while playing with my back to a wall also suggests that the back of the bass contributes substantially to the sound. I have often thought that my body dampens the sound more than anything else could although probably not as much as Ken's. :o

However, it is plausible that anything that dampens the bridge, the strings, or the afterlengths could have a greater effect because these precede the body vibrating and something that dampens these would decrease the energy flowing to the body of the bass, before it gets there.

It would be interesting to put a mic on the back of the bass and see how much signal we might get and what the differences are. I know very careful mic'ing of drums in the studio often involves two mics to produce something closer to the live sound of the drum. It might be interesting to mic a bass from in front and in back. Hopefully there wouldn't be any phase cancellation.

Dampening and Mic'ing
 

Yo, it's all in the technique. ;)


I think I have tried a Mic in the Back at one time and it was a boomier, less direct type of sound. I don't know if any phase cancellation would happen and/or why it would or would not. It would probably just be the same as if the Bass is just louder as far as any Wolfs or Note Cancellations.

Different mics, different positions
 

I was involved in a bass mikng technique class for live sound engineering students a few years ago as the demonstrator. I don't recall any real details about the mics used, but the instructor hung one of the mics from behind my bass, over the scroll, and got a wonderful, natural sound through the system. I had never seen that technique used before or since, but I imagine that unless you were playing solo, that mic would pick up every thing else on stage.

Actually, I was thinking of the muting effect from the mass of the mic & foam rather than the amount of sound radiated by the instrument. However, measuring the relative amount of sound radiated from the back, sides and top is quite easy. A simple $30 Radio Shack ****og volume meter works quite nicely. That's what I use to determine the A0 frequency inside the bass. I bought it originally for setting up my home surround sound system.

okkkk
 

Bob, you can ABC my Basses anytime you like. I don't personally buy into that theory mainly because I am clueless about it. Changing strings for me has made more differences than just about any type of adjustments have.

Maybe it also depends on the grade of Bass too. You think?

No Theory Here
 

What theory? That a Radio Shack volume meter will allow you to determine the relative amount of sound coming from the back, front, ribs or any other part of your bass? The only thing I said was the I use it (the Radio Shack ****og volume meter) to determine the A0 frequency (by measuring the volume) inside the bass. No theory here either, just the fact that I find this inexpensive volume meter quite useful for lots of things. It's also a fact, not theory, that I used it to setup my home surround system, which I might add sounded quite good after making the adjustments to the individual spreaker channels.

I assume that you were jumping to a conclusion that this had something to do with A0-B0 matching. No, I gave up trying to convice you of the merits of that and other well documented proceedures that I use a long time ago.

oops..
 

Ok Bob, sry.. My bad.. I mis-read your Post. For judging the volume of the Top or Back or whatever, I just use my ears. I don't know what measuring them could do if that's how the Bass just is. On the AO/BO thing, I'm more of a 'see it' kinda guy than a 'read about it' person. I need to experience things for myself before I tinker with things. The A-B thing is for another thread some place else on the Forum so we will leave it at that. I know we did this over on TB before but I would welcome the open type discussion of it if you are willing to start it up again over on the Luthiers section here.

Thanks for the offer on A0-B0 Ken, but I got my fill of discussing it over on the TalkBass Forum. It was unfortunate that none of the luthiers over there were unwilling to seriously look into it and try it for themselves, preferring to declare it bogus and putting me in an adversary role defending the concept. I can only say that I have used the process successfully on many basses and believe that it is tool that should be in every luthier's shop. After going through that rather unpleasant experience on TalkBass, I made a personal decision that I will not discuss it any longer on any forum or Internet discussion group. However, I am always available to answer legitimate questions from anyone who is truly interested in trying A0-B0 matching by email or PM. I have sent out many copies of my 1996 Michigan Violin Makers Assn Paper on A0-B0 matching in basses to interested individuals as email attachments. The same offer also applies to questions about the Vibration DeDamping process which we briefly touched on in an earlier thread on this forum.

well...
 

Ok, on that note, I would like to have one of each for my reading and files. I am sure there is something to gain there if one makes the effort. I on the other hand have been fortunate enough to choose Basses that need very little help other then the obvious repairs needed. Maybe I have done some matching on my own but didn't know I was doing it. I have set-up and improved quite a few basses in my time going by just feel. It would be good to see this in print. Maybe some others here would try this and discuss their results and that way we could have an A/B forum that you might, just might visit on occasion and give a shout once in a while.. That would be nice.