How to increase dispersion?

[Devo-lution]

Hi

My current favourite cab is a good ol' (early 90's) Trace Elliot 2x15. Vertical stacking, celestion speakers and a sound which I simply adore. No tweeter or midrange driver.

A sound which I adore... I adore... but some musicians I regularly play with are not so impressed.

I always make sure that I'm standing on-axis (cab raised to ear-level). The musicians that complain are usually the ones standing completely off axis. One drummer told me he could only hear muddy lows.

Is there some way of increasing the dispersion of this cab without messing up it's sound? Like an external midrange driver or...

Thanks a lot

[JimmyM]

You could do a separate mid driver, but impedance could be an issue unless you use a small amp for it. One thing you might try is lining out to a little guitar combo with an 8". Just roll off all the lows so you don't blow it and let it carry the upper mids and highs for the band. The 8" will have better dispersion for those freqs than anything bigger. Not exactly sure how much wattage you'd need for it, but I would think maybe around 50w would do it. Don't know if they make 50w guitar combos with an 8" but you could also do it with an 8" bass combo if you can't find a guitar amp that'll fit the bill.

[BogeyBass]

Just keep going vertical with another 2x15
if you dont want a mid or tweet

otherwise do it like its always been done , keep going vertical with midrange drivers
and use a bi amp system or crossovers

[Devo-lution]

Originally Posted by BogeyBass

Just keep going vertical with another 2x15if you dont want a mid or tweet

otherwise do it like its always been done , keep going vertical with midrange drivers
and use a bi amp system or crossovers

That would be, simply put, HUGE

Although lots of people say you can do it, I'm hesitant to run another 4 ohm 2x15 which would bring the impedance down to 2 ohm. I use a tube amp with output transformers for 4 ohm and 8 ohm.

And well, it wouldn't fit in the trunk of my car anyways .

Like I said, for me everything sounds fine. This trace beast is surprisingly strong in the mids and lower treble area.

@ Jimmy, good suggestion, but would it cause phase probs?

[Derek Kiernan]

Originally Posted by Devo-lution

I always make sure that I'm standing on-axis (cab raised to ear-level). The musicians that complain are usually the ones standing completely off axis. One drummer told me he could only hear muddy lows.

Maybe the thing to do is stand off-axis? If you EQ to make it sound right further to the side, what your bandmates hear will be much closer to what you do.

Unless you can show frequency response and impedance charts, people might have a hard time giving suggestions on how to successfully implement a mid-driver. Maybe it's worth trying to audition a cab such as a fEARful?

[BogeyBass]

Originally Posted by Devo-lution

That would be, simply put, HUGE

Although lots of people say you can do it, I'm hesitant to run another 4 ohm 2x15 which would bring the impedance down to 2 ohm.

@ Jimmy, good suggestion, but would it cause phase probs?

Yes it would be huge and sound huge
here is a vertical stack of Sunn 200s 2x15 cabinets


of course their is phase problems with a 15" and 8" thats why you need crossovers like any 2 way speaker system.
otherwise the quick and dirty solution by jimmy was to use the EQ as a pseudo crossover. could work but not very accurate

and yes the lower the impedance, the load will draw more current. So in a tube amp you will overheat a 4ohm winding if you run a 2ohm load...otherwise a 8ohm load on a 4ohm winding would pull less current and not damage the winding. The sound would just be degraded from the impedance mismatch.

[Jools4001]

Sounds like you really need a fEarful 1515/66, but failing that you could try making something similar to a fEarful headcase which consisted of a small case designed to fit on top of a a speaker cab with an 18sound 6ND410 or 6NM410 mid driver and a tweeter in it (you could leave out the tweeter if it's not to your taste). The headcase also had a crossover in it so that only frequencies above 800hz or so were fed to the mid drivers, frequencies below that were directed to the 12 or 15 inch subs that the headcase sat on. It's the mids that will start to focus themsleves into a narrow beam when a bigger driver tries to reproduce them, so handing the mid duties off to a specialist smaller speaker will give you a wider dispersion. I'm pretty sure your current rig will be 4 Ohms if it has two speakers, so you may need two mid drivers as well to match the impedance, running them through a crossover will mean that your amp will still see a nominal 4 ohm impedance.

You should be able to find out more by searching on headcase

I think that crossover design is a specialist art that really needs an understanding of the characteristics of each driver, the enclosure etc etc, but there may be generic crossovers that are suitable.

Caveat: All this is from memory, and I'm not an expert, just a punter with enough knowledge to be dangerous....somebody who really knows what they're talking about mught be along soon

[JimmyM]

Originally Posted by BogeyBass

of course their is phase problems with a 15" and 8" thats why you need crossovers like any 2 way speaker system.
otherwise the quick and dirty solution by jimmy was to use the EQ as a pseudo crossover. could work but not very accurate

I was operating under the assumption that Devo wanted to keep his Trace 215. Otherwise I probably would have suggested a 2 or 3 way cab neatly crossed over. Adding the combo actually works pretty well. Not as accurate as using crossovers but accurate enough.

Now the second 215 could possibly work, but to get dispersion of upper mids and highs onstage, you have to crossfire them. Not exactly sure of the best way to do it, but I've seen guys like Bill FM and Duke talk about it. Seems like a lot of work, though. And if you just stack them vertically facing the same way, then you're only going to get a twice-as-tall stack with poor dispersion. If it were me, I'd rather lug a small combo to put on top I wonder if something like the Phil Jones Briefcase might work for that...

[Devo-lution]

Originally Posted by JimmyM

I was operating under the assumption that Devo wanted to keep his Trace 215. Otherwise I probably would have suggested a 2 or 3 way cab neatly crossed over. Adding the combo actually works pretty well. Not as accurate as using crossovers but accurate enough.

Now the second 215 could possibly work, but to get dispersion of upper mids and highs onstage, you have to crossfire them. Not exactly sure of the best way to do it, but I've seen guys like Bill FM and Duke talk about it. Seems like a lot of work, though. And if you just stack them vertically facing the same way, then you're only going to get a twice-as-tall stack with poor dispersion. If it were me, I'd rather lug a small combo to put on top I wonder if something like the Phil Jones Briefcase might work for that...

Correct Jimmy. I like the sound of the trace and wouldn't want to part ways with it. Mic'd, it does the trick live. I also have another cab, but that's a 115 so... same problem, even worse.

I'm not really losing any sleep about this or whatsoever, but I am noticing I'm losing "space" in my new wave band over the last months. We have five musicians playing at the moment (three guitars or two guitars and a synth). Guitar players are all young folks (like me) and become instantly disgusted if asked to not play for like... one minute. Due to the extra members and mix density, I had to simplify my bass playing... no problem there, as I am not necessarily one who needs to play busy.

But now I start having the feeling that my ideas during jams don't have the same impact as they used to have. Often, the others don't seem to follow as intuitively as they used to. When confronting the bandleader, he said he could hardly hear me behind his drums when using the 115. The 215, according to him, does better. But this got me thinking about ways to improve the dispersion, as a lot of our song ideas are born out of jams.

[Devo-lution]

Originally Posted by JimmyM

I was operating under the assumption that Devo wanted to keep his Trace 215. Otherwise I probably would have suggested a 2 or 3 way cab neatly crossed over. Adding the combo actually works pretty well. Not as accurate as using crossovers but accurate enough.

Now the second 215 could possibly work, but to get dispersion of upper mids and highs onstage, you have to crossfire them. Not exactly sure of the best way to do it, but I've seen guys like Bill FM and Duke talk about it. Seems like a lot of work, though. And if you just stack them vertically facing the same way, then you're only going to get a twice-as-tall stack with poor dispersion. If it were me, I'd rather lug a small combo to put on top I wonder if something like the Phil Jones Briefcase might work for that...

Yeah, I thought about those too when you said that.

You also have these tiny tube combo's for guitar using 6' and 8' drivers. Vox and Fender offer these. Downside is that they only come as 5 watt amps. (vs my 110 watt bassman inspired regular amp)

Maybe, If highpassed out of the range of the 15's and driven into mild saturation, they'd keep up... But that's a big maybe there.

[bertbass666]

I'm assuming that the band has some kind of foldback system so why not just D.I. or mic your bass and send it through the monitors to the other band members with little or no bass EQ?

[alexclaber]

There isn't really anything you can do to solve the dispersion issue without changing the tone, save adding another matching cab and stacking it so it fires sideways, which is impractical to say the least!

However there are two things that will help - one is freeing up some space for the bass by changing the EQ on the guitars and synths (this will take some negotiational skill but it's worth persevering!) and the other is to always position your cab as far back on the stage as possible, pushed right into a corner and firing diagonally across the stage, not forwards (thus bringing the rest of the band closer to being on-axis with the woofers).

[billfitzmaurice]

Originally Posted by Devo-lution

Is there some way of increasing the dispersion of this cab without messing up it's sound? Like an external midrange driver or...

A midrange driver(s) is the only viable option, and yes, it will change the sound, as it would assume the load above 1kHz to 1.6kHz.

[oldcatfish]

Quote "One thing you might try is lining out to a little guitar combo with an 8 inch"

Better yet, line out to either a small bass combo amp or powered speaker. Just enough volume for the others to hear what they need...think of it more as a separate monitor for the drummer, etc. It should NOT be loud enough that it competes with your amp/speakers.

[Gearhead17]

Originally Posted by Devo-lution

Hi

My current favourite cab is a good ol' (early 90's) Trace Elliot 2x15. Vertical stacking, celestion speakers and a sound which I simply adore. No tweeter or midrange driver.

A sound which I adore... I adore... but some musicians I regularly play with are not so impressed.

I always make sure that I'm standing on-axis (cab raised to ear-level). The musicians that complain are usually the ones standing completely off axis. One drummer told me he could only hear muddy lows.

Is there some way of increasing the dispersion of this cab without messing up it's sound? Like an external midrange driver or...

Thanks a lot

Everything below 200hz, basically goes every direction possible. The higher up from 200hz you go, the more directional the sound becomes. You probably hear yourself just fine and as you are standing in front of it while the drummer is right, all he can hear is muddy low end. The only way for everyone else to hear you is to get your bass tone in the monitors or set up another bass rig on the other side of the stage (preferably the same thing or a smaller version of it) so everyone can hear you better. You could turn the cab more towards your band mates, but if you are supplying the sound for the show (no PA), might as well keep pointing it towards the crowd.

You would have to put speakers on the side of your cab for others to hear you more clearly.

[billfitzmaurice]

Originally Posted by Gearhead17

The only way for everyone else to hear you is to get your bass tone in the monitors or set up another bass rig on the other side of the stage (preferably the same thing or a smaller version of it) so everyone can hear you better.

Doing so would make things worse, as there would be cancellation modes in the low end. Putting the bass into the monitors is OK, but only do so high-passed at 150 to 200 Hz, so that the multiple sources don't result in low frequency cancellation modes. Below that the omni-directional radiation pattern of the bass cab covers the entire stage.

[IvanMike]

Originally Posted by Devo-lution

Correct Jimmy. I like the sound of the trace and wouldn't want to part ways with it. Mic'd, it does the trick live. I also have another cab, but that's a 115 so... same problem, even worse.

I'm not really losing any sleep about this or whatsoever, but I am noticing I'm losing "space" in my new wave band over the last months. We have five musicians playing at the moment (three guitars or two guitars and a synth). Guitar players are all young folks (like me) and become instantly disgusted if asked to not play for like... one minute. Due to the extra members and mix density, I had to simplify my bass playing... no problem there, as I am not necessarily one who needs to play busy.

But now I start having the feeling that my ideas during jams don't have the same impact as they used to have. Often, the others don't seem to follow as intuitively as they used to. When confronting the bandleader, he said he could hardly hear me behind his drums when using the 115. The 215, according to him, does better. But this got me thinking about ways to improve the dispersion, as a lot of our song ideas are born out of jams.

your issue is NOT dispersion - it's frequency slotting in the mix, particularly in the stage mix. How do I know? The above post.

Good chance that you and the guitars and synth are putting out most of your sonic energy in the same bandwidths. Bass tends to be the first thing that "disappears" (at least in people's minds) in situations like these. Outside of making sure you have no volume wars issues, you and the other musicians need to figure out where everyone is going to "live" sonically. This may (will) require some EQ tweaks that people will not like when their instrument is played solo.

Oddly enough, instruments aren't played solo in bands much.