Double Bass AMT through AI Clarus+ head . . . but then?

[KontraKurt]

One year ago I decided to upgrade my double bass sound. When putting the bass close to a wall one can hear the excellent natural acoustic sound that the bass is capable to give. That is the sound I am looking for. So I bought an AMT and connect it through a TAPCO mixer and then into my old Roland Cube 60 bass amp. However, that was not any success. I am completely lost and uneducated when it comes to electronic stuff like this. I learned that that kind of amp is not useable for giving a relevant sound from an acoustic condenser microphone.

So after careful consideration I asked my dealer to make an order for the new Acoustic Image stuff that have taken 12 months of design work. The new products “...providing the ultimate in gigging flexibility”. Sounds good.

Yesterday I received the brand new Combo. The amp is the new 2 channel 800W Clarus+. The cabinet is the new Ten2EX down firing 10 inch Woofer and 2.5 inch Tweeter. The cab has front legs for tilting the unit.

I followed the instructions carefully. It says that you start having MASTER at 12 o’clock. The Volume LEVEL at zero (7 o’clock) and the three EQ at 12 o’clock. The cabinet was tilted and the Room Coupling Control at its start position at 100% and the Tweeter Level Control at its start position at 0 dB as well. On the amp the phantom power was of course activated and all FILTER´s were unactivated.

When turning on the amp and set the LEVEL at 9 o’clock the windows and paintings start shaking like it was an earthquake. It sounds like somebody banging a plywood board with his clenched fist in a rap tempo.

I try to manage the problem with the FILTER´s in different settings and the EQ´s in different position from 9 to 3 o’clock. But the more I adjust the more I lose from the nice AMT sound. Of course I also put the Room Coupling Control and the Tweeter Level Control in its 3 alternative positions but it does not help either.

The notes Bb B C Db D on the A string represent the worst part of the chromatic scale over the all bass. (I have played the bass recently through head phones so there is no trouble with the bass). When tuning that problem away with the LEVEL control the resisting volume is so low that the amp is no longer necessary - I can hear the acoustic sound from the bass but nothing from the cab.

Just for checking I connect my old Underwood and found out that it works without any kind of booming at all. So the problem is obviously the connection between the AMT and the Ten2EX. My intention is to run the AMT over the CLARUS+ but replace the cabinet with something else.

How do you run your AMT through an AI Head? Can you give me some hints?

Please put brands and type number when referring to speakers or cabinets.

 

[wiro]

I guess you're trying with too much volume in too small venues where resonances occur easily.

To my humble opinion the AMT is only usefull in a studio with a headphone. I know opinions differ but as far as I've read all the bassists that use the AMT in a live situation either send the signal straight to FOH or are using an amp with no more power than 100 watt. You're talking 800!

Live I'm using the Clevinger Natural Presence pu through one channel of the Focus (= the same as the Clarus+) and the new Vector condenser mic through the other. The latter is a lot less prown to feedback than the AMT. Still I can't turn it up more than about a quarter before feedback occurs. So the volume and the punch to cut through the mix must come from the pu.
Is it an option to combine your AMT with the Underwood?

 

[Steve Freides]

You ought to try changing some of the parameters you don't mention, e.g., how far your bass is from the speaker, what room you're in, etc.. The AI gear puts out what comes in, so if you've got feedback, you've got a resonance or peak response somewhere, and if that's part of what you in your sound, then you have try less amplification, more distance between pickup and speaker, or a different room. I can't think of many more variables (although I'm sure I'm overlooking some).

-S-

 

[William Hoffman]

Kurt

i've used the AMT S25B for about 5 years, now with and AI Focus (essentially the Clarus+) and often with an older Contra Ex. from reading your post, it seems you need to take the time to figure this new rig out, and the name of the game is trial and error, and lots of patience. you just got it yesterday, right?

with the AMT you have a condenser mic, and a pretty good one which reduces bleed and feedback. mentioning the Underwood is like comparing apples and oranges. a piezo pickup does not feed back like a mic. but it doesn't give you the sound of your bass as well, either.

there is the position of the mic in relation to the bass.

you must experiment with where you position the AMT on your bass. i know, the pictures AMT has put out for promotional purposes shows the mic pointing right smack dab into the f-hole. but imho that is exactly the wrong place to position the AMT if you want to avoid proximity effect, muddy sound, and lots of feedback. you want it to sound like you hear your beautiful bass, right? i find the AMT needs to be somewhere in the middle of the top, maybe an inch and half away.

then there is the position of the bass + mic in relation to the cab.

in smaller or boomier rooms, the Clarus HPF can be a great help. start out with it set at 0 and move it around clockwise till you get maximum volume before feedback. then on to EQ tweaking. but if you want to play loud you will have to struggle with the feedback monster. put your cab(s) out front of you or pointed away from your mic, etc. it also helps to get the cabs off the ground. use the tilting mechansim of the Ten2X. or put the cab up on a chair or a box of some kind, especially if you are on a portable stage or anywhere the floor can transmit between bass and amp, contributing to feedback.

as for EQ, Rick at AI told me it's more effective to leave the AI EQ knobs close to 12 o'clock, just tweaking them a bit to the left or right, maybe at 11:30 or 12:30, but not as far as you are going.

to allow for bowing, i attach the AMT gooseneck to the lower C bout of the E string side and put the mic out in the middle of the top just below the bridge. that gives better manoeverability with the bow, which can strike the gooseneck owch! if you have it on the G side.

also, if you have the gooseneck version of the AMT, you also have to make sure the AMT is clamped on tight enough. if it can vibrate at all, you will get a horrible rattling sound out of the amp. but it is not the amp's fault, it's the rattling sound of the AMT. if you have the tailpiece mount, maybe no problem...

works for me, even live. i hope that's helpful.

Bill

ps where are you located? your profile could be filled in.

 

[uprightbass.com]

I'm assuming that you have it in front of the F hole like it was designed to do. Not to throw more confusion into the situation, but the F hole is the worst place to mic to get an accurate sound on the bass (ask any professional studio engineered who's done a lot of micing on the upright bass). Put your ear in front of the F-hole and play and ask yourself is this the sound you want to amplify?

I did a small writeup about it.
[Invalid or Expired Link Removed]

 

[Ric Vice]

Yesterday I received the brand new Combo. The amp is the new 2 channel 800W Clarus+. The cabinet is the new Ten2EX down firing 10 inch Woofer and 2.5 inch Tweeter. The cab has front legs for tilting the unit.

......I followed the instructions carefully. It says that you start having MASTER at 12 o’clock. The Volume LEVEL at zero (7 o’clock) and the three EQ at 12 o’clock. The cabinet was tilted and the Room Coupling Control at its start position at 100% and the Tweeter Level Control at its start position at 0 dB as well. On the amp the "phantom power" was of course activated" and all FILTER´s were unactivated.

Kurt,
Unless your AMT is radically different from my older one the AMT's own pre amp supplies the phantom power to the mic. I would think that powering it up with 48 v from the Clarus+ would not be a good idea and in fact could be the cause of the problem. Try switching the Clarus + phantom power off.

When turning on the amp and set the LEVEL at 9 o’clock the windows and paintings start shaking like it was an earthquake. It sounds like somebody banging a plywood board with his clenched fist in a rap tempo.

Since there are two level controls on the Clarus + I'm assuming that you are talking about the pre amp level control. Most of the newer amps work best when you set the power amp level around 12 and increase the pre amp until you reach the desired volume.

I try to manage the problem with the FILTER´s in different settings and the EQ´s in different position from 9 to 3 o’clock. But the more I adjust the more I lose from the nice AMT sound. Of course I also put the Room Coupling Control and the Tweeter Level Control in its 3 alternative positions but it does not help either.

The notes Bb B C Db D on the A string represent the worst part of the chromatic scale over the all bass. (I have played the bass recently through head phones so there is no trouble with the bass). When tuning that problem away with the LEVEL control the resisting volume is so low that the amp is no longer necessary - I can hear the acoustic sound from the bass but nothing from the cab.

AI amplifiers are very neutral sounding. Great on many basses!

Just for checking I connect my old Underwood and found out that it works without any kind of booming at all. So the problem is obviously the connection between the AMT and the Ten2EX. My intention is to run the AMT over the CLARUS+ but replace the cabinet with something else.

Since the Underwood is mounted in the wings of the bridge it tends to
have a pretty well defined midrange, with less bottom. On some basses it works very well. I owned one. I find that the AMT works very well blended with a pickup and the Clarus + has all the bells and whistles to accomplish just that.


Not sure that you need to do that just yet. Why don't you give it a little time.

How do you run your AMT through an AI Head? Can you give me some hints? Please put brands and type number when referring to speakers or cabinets.

Personally I use the AMT from the AMT Super Pre Amp directly into my Walter Woods Ultra and a Realist into the Second Channel.

Ric

 

[William Hoffman]

I'm assuming that you have it in front of the F hole like it was designed to do...

a few years back i spoke with Marty at AMT (who is the designer of the S25B mic), and apparently the pictures you see of the AMT were taken to look good for advertising but in practice are misleading in that respect. the AMT is not designed or intended to be positioned over the f-hole. Lawrence if that was a typo, then no matter, please disregard.

your other statement may have general validity, i don't know, i've only worked with about 3 mics so far. i do position my Neumann KM185 "over" the f-hole, at a distance of 3 inches out, but pointing at an angle toward the middle of the top between FB and bridge, with very good results.

...Unless your AMT is radically different from my older one the AMT's own pre amp supplies the phantom power to the mic. I would think that powering it up with 48 v from the Clarus+ would not be a good idea and in fact could be the cause of the problem. Try switching the Clarus + phantom power off. Ric

Ric, if Kurt is not using a battery in the AMT preamp, then it is perfectly ok to use the phantom power from the Clarus. i do that quite often, and it works just as well. sometimes i've even accidentally used both battery and phantom and so far no harm done but, yes, that is not needed. fwiw Marty said it might cause damage, but i never had any bad sound because of that. Bill

 

[KontraKurt]

Thanks guys for your support. Electronic stuff like this is not my cup of coffee. My cup is playing bass.

Yesterday, my dealer asked me if I have put the jumper cable in place as a connector between the amp and the cab. “Which jumper cable”, I asked. AI missing out to send it in the package! Ric have sent it today. He said that the missing cable can solve the problem. Will see if it helps. I put in place an ordinary instrument cable because the two NEUTRIK SPEAKON Twist Lock Connectors have a 1/4” phone jack in the ends. Every day is a day in school.

William, I living in Mallorca, Spain. Here is no luthier so you have to do as much as you can by your own. Today I found the right glue for reparing a small crack on my bass in a carpenters work shop. He play violin and was fixing a crack on it! What a direct hit!

 

[William Hoffman]

...Yesterday, my dealer asked me if I have put the jumper cable in place as a connector between the amp and the cab. “Which jumper cable”, I asked. AI missing out to send it in the package! Ric have sent it today. He said that the missing cable can solve the problem. Will see if it helps. I put in place an ordinary instrument cable because the two NEUTRIK SPEAKON Twist Lock Connectors have a 1/4” phone jack in the ends. Every day is a day in school.

William, I living in Mallorca, Spain. Here is no luthier so you have to do as much as you can by your own. Today I found the right glue for reparing a small crack on my bass in a carpenters work shop. He play violin and was fixing a crack on it! What a direct hit!

i hope you got it sorted out with the new rig. please post your results.

yes, an instrument cable can even damage your amp or cab. you need to watch out for that. the speakon twist lock connectors assume you will use a speaker cable.

i hope that was hide glue (hautleim).

cheers

 

[dar512]

Yesterday I received the brand new Combo. The amp is the new 2 channel 800W Clarus+. The cabinet is the new Ten2EX down firing 10 inch Woofer and 2.5 inch Tweeter. The cab has front legs for tilting the unit.

Ric, I'd love to hear a review of the Ten2EX when you've had a chance to put it through its paces.

 

[Ric Vice]

Ric, I'd love to hear a review of the Ten2EX when you've had a chance to put it through its paces.

Dar 512,
Somehow the quotes got confused, Kontra Kurt has the Ten 2, not me.
My current rig is a Walter Woods Ultra or Walter Woods MI-400-8 into either a EA VL 108 or EA VL 208. It's pretty old school at this point, but I'm used to it and it gets me the sound I'm looking for. I do have the new Headway EDB-1 and it's incredible. That pre amp sounds great. Very similar to the older Walter Woods heads but with a five band EA section.

Ric

 

[Ric Vice]

Ric, I'd love to hear a review of the Ten2EX when you've had a chance to put it through its paces.

Dar 512,
Somehow the quotes got confused, Kontra Kurt has the Ten 2, not me.
My current rig is a Walter Woods Ultra or Walter Woods MI-400-8 into either a EA VL 108 or EA VL 208. It's pretty old school at this point, but I'm used to it and it gets me the sound I'm looking for. I do have the new Headway EDB-1 and it's incredible. That pre amp sounds great. Very similar to the older Walter Woods heads but with a five band EA section.

Ric

 

[KontraKurt]

i hope you got it sorted out with the new rig. please post your results.

i hope that was hide glue (hautleim).

cheers

Yea, man! Glue based on animals bone.

 

[KontraKurt]

An other month and still problems when trying to have the AMT and AI Clarus+/Ten2EX working together.

My old Underwood pickup works incredible with the AI Unit. But that is not the sound I am struggling to achieve. I want the sound as acoustic as possible so it made sense to go over the AMT and AI.

I have moving around the AMT and found out that the best place is between the f-hole and the bridge G-bone.

I cannot go over 9 o´clock with the Clarus LEVEL-control without having a terrible feed back. AI, Rick Jones, says that the signal from the AMT S25B (not SP25B) perhaps is too strong. He recommend a 10dB attenuator. However, I have a TAPCO mixer which can work as a damper also, I think. So I connect the AMT through the mixer but it does not work so much better - but little.

The crux of the matter is feed back, boomy bass, overtones and not much acoustic sound at all.

AMT, Ron, says that AMT not goes well with the AI combos. He recommend active speakers instead.

The AMT works good in the jazz club PA-system so there is no faultiness with the micro phone.

The sound from Underwood is great and no sign of weakness means that the bass is alright.

Many DB players says that condenser microphones works better if you cover the f-holes.

Other DB players says that AI amps and combos are tricky in small rooms and tiny clubs. I thought that AI has overcome those shortcomings with the brand new Ten2EX that I have now.

So why doesn´t the stuff work properly?

 

[William Hoffman]

Kurt

from your description, i'd say you are positioning the mic too close to the f-hole. i had mine there for a time, but the sound is too muddy and the feedback was a real big problem. i would recommend positioning the mic more or less in the center of the bass.

if you have the gooseneck AMT, try attaching it on the "E" side C bout with the mic positioned in the middle of your bass just below the bridge. i put mine there, at a distance of about 3 or 4 cm from the top. with the Clarus HPF i can usually handle just about any room, but rooms vary. i don't get that thick boomy sound in that spot but a more natural "my bass only louder" sound there.

good luck

Bill

 

[AMJBASS]

Positioning the AMT right between the bridge feet, and a little towards the fingerboard also is a great spot for it. You shouldn't have too much difficulty with that rig. If you are trying to blend the pickup with the mic, I would use the mic for the mids and highs only. Cut the low end out on it and you should get less feedback. Also, cut the highs out on the pickup channel and bring the mic in until you get a good balance.

 

[KontraKurt]

Thanks for fast support, Bill and Adrian.

I will try. Coming back soon.

 

[KontraKurt]

Much better! But still to boomy. Position: center 4 cm under the bridge (not between the legs). Max LEVEL possible 9 o´clock. That is strange seeing that the max. potential is 4 o´clock.

Are you using an attenuator?

 

[Ric Vice]

Much better! But still to boomy. Position: center 4 cm under the bridge (not between the legs). Max LEVEL possible 9 o´clock. That is strange seeing that the max. potential is 4 o´clock.

Are you using an attenuator?

Kurt,

If you have the tailpiece mount, try setting the mic up with the gooseneck between the feet of the bridge that will put the mic above the bridge directly below the fingerboard. This is the only spot that works for me.

 

[KontraKurt]

Kurt,

If you have the tailpiece mount, try setting the mic up with the gooseneck between the feet of the bridge that will put the mic above the bridge directly below the fingerboard. This is the only spot that works for me.

Do you have a picture showing the position?
Have tried your suggestion and put the mick in different positions up and down under the strings. You know I am looking for that woody sound.