Jump to content
Why become a member? ×

Bass stacks full range vs bi/tri-amped via crossover


coully
 Share

Recommended Posts

Bass stacks and crossovers

--------------------------------------------------------------------------------

At risk of sounding naive, I have a question about using speakers of different sizes in a stack (say 1x15 and 4x8 as an example).

If in a PA you would use an active crossover to direct the sound to the most appropriate speaker (bass/mid/high to the appropriate box) why would you not do this in a bass rig??

Speakers with tweeters or HF compression drivers normally have a crossover network internally but with separate speakers the rule seems to be to drive them with exactly the same frequency range regardless.

Has anyone experimented with doing this and if so, what were the benefits or drawbacks? How did you set the rig up?

Are there pre-amps or amps which support this kind of approach?

Thanks in advance

Link to comment
Share on other sites

Generally you need seperate power amps for each frequency band. Obviously you could use a stereo power amp for a bi-amp. Some bass heads have built in crossed-over outputs, but these generally need a power amp after anyway.

I think Trace did an amp with seperate speaker outputs for hi and low?

Link to comment
Share on other sites

[quote name='coully' post='549148' date='Jul 23 2009, 04:51 PM']Bass stacks and crossovers

--------------------------------------------------------------------------------

At risk of sounding naive, I have a question about using speakers of different sizes in a stack (say 1x15 and 4x8 as an example).

If in a PA you would use an active crossover to direct the sound to the most appropriate speaker (bass/mid/high to the appropriate box) why would you not do this in a bass rig??

Speakers with tweeters or HF compression drivers normally have a crossover network internally but with separate speakers the rule seems to be to drive them with exactly the same frequency range regardless.

Has anyone experimented with doing this and if so, what were the benefits or drawbacks? How did you set the rig up?

Are there pre-amps or amps which support this kind of approach?

Thanks in advance[/quote]

Yes ideally you should split any amp signal to different cabinets with different characteristics (like a 115 and 410) through a crossover to avoid diffrent speakers competing within the same frequency range.

Thats what you do with PA but a lot of bass amp manufacturers just want to market the simplest good looking rig that will sell by the truckload, then the end user wonders why it doesnt sound so great even though theyve got a 115 + 410 600 watt rig behind them :)

There are plenty of power amps, preamps and crossovers that will allow a bassist to achieve that.

Link to comment
Share on other sites

[quote name='coully' post='549148' date='Jul 23 2009, 11:51 AM']Are there pre-amps or amps which support this kind of approach?[/quote]There are, but there aren't any speakers from electric bass cab manufacturers that support this approach, so your options are to use PA gear or build your own.

Link to comment
Share on other sites

Bi/tri-amp rigs need to be designed from the ground up as a complete system. Unfortunately the only systems I can think of like this a Forge and IP Technologies they are both heavy and expensive. And doing this through mixing and matching gear yourself will also end up big and heavy (though not necessarily expensive if you hunt around the used market) but it does require a fair amount of expertise to end up with a successful rig.

The killer for bi-amp rigs was companies encouraging bassists to send highs to their 4x10" and lows to their 1x15", omitting to consider that the 15" speakers they were using could put out less bottom than the 4x10"!

Alex

Link to comment
Share on other sites

You'd need a stereo amp and a pre-amp which had a built in x-over.

An old SM400 with bi-amp and you can pick them up for reasonable money.
You have 200watts per side into 4 ohms...so a bit low-powered maybe these days..

SM500 is 250 watt per side.

Eden do the same as well..not sure of the models...

or the pre-amp route, a DB680 with x-over outs into any stereo power amp

That way you can control the freqs into which cab..upto a point from the amp..and also the power output..

Link to comment
Share on other sites

'If' you can sort out the cab issue, then the old faithful GK800rb has a built in X-over with separate 300w + 100w power section, which can operate full range or bi-amp. Great amps but if putting through a 'normal' full range bass cab you may find it sounds better in full range mode! :)

Link to comment
Share on other sites

I do this all the time. My big rig is tri-amped and used to be a quad amp set up. In that rig I use a DBX speaker management system and it all fits in a 8U rolling rack, including power amps. I use the large rig for showbands, disco bands, motown party band work.

My small 2U rig now feeds a 1x15, and 4 X 5 in a vertical array, in two separate boxes. The preamp is an Alembic with a crossover (12db Slope) and I use a 1U CARVER Power amp. I use this mostly and it will do most of what I do, which is jazz trio, quartet, quintet, or small pop/country outfits, which 90% of what I do. Sometimes I use a different 3U rig for EUB, which has a READ preamp or RANE AP13, a DBX crossover, and a Carver poweramp - same idea but diff. components, better crossover slopes, but 1U more. The latter works better for Piezo pickups as I can shelf off the subsonic low end with the DBX crossover. I use the 3U rig to feed the same 1X15 and 4 X 5.

Edited by synaesthesia
Link to comment
Share on other sites

[quote name='JTUK' post='549281' date='Jul 23 2009, 06:53 PM']You'd need a stereo amp and a pre-amp which had a built in x-over.

An old SM400 with bi-amp and you can pick them up for reasonable money.
You have 200watts per side into 4 ohms...so a bit low-powered maybe these days..

SM500 is 250 watt per side.

Eden do the same as well..not sure of the models...

or the pre-amp route, a DB680 with x-over outs into any stereo power amp

That way you can control the freqs into which cab..upto a point from the amp..and also the power output..[/quote]

Eden models WT600 and WT800 have in built variable crossover and stereo power amp sections.I use these features on my rig ,flipping in between full range and bi-amp,which normally gets the sound i want.
Older peavey megabass rack heads had these facilities as well and can be picked for quite reasonable money.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...