Bi-amping by frequency or via pickup?

[jazzyvee]

My bass has the option of mono, both pickups through one jack or "stereo" one pickup out per jack. I have volume and tone circuit for each pickup and an overall master volume.

I want to do some experimenting with bi-amping and wonder if anyone has tried it yet and what were your thoughts on how successful /unsuccessful the venture was.

1) Is it better split the signal by frequency and use a mono out from the bass into my pre-amp with a crossover to a stereo power amp sending the lows to one cab and the higher frequencies to another cab.

2) Is it better to use the individual outs from each pickup to separate pre-amps then to the stereo amp and to one cab per pickup.

I can imagine for some genres there would be no benefit like for example reggae when the higher frequencies are not so important to the tone but for genres of music where you need the full spectrum I wonder if there is anything I can gain. I will be using 2 x F1-x pre-amps, SF2-superfilter, QSC plx2402 and two mesa boogie cabs.
I'm not looking for huge volume I'm trying to get the best and cleanest sound quality I can from the gear I have.


Any pro's or cons would be good to hear.

Jazzyvee

[LukeFRC]

surely (and there are more who know more than me) but the benefit of bi-amping is splitting the signal to drivers that are best able to deal with that portion of the signal. The low end to a bass driver and the mids to a midrange driver etc. The crossover(s) you use will need to be right. I don't see much benefit of sending each pickup to a different amp if you're trying to get the "best and cleanest" sound.

[subrob]

[quote name='LukeFRC' timestamp='1384212192' post='2274185']
surely (and there are more who know more than me) but the benefit of bi-amping is splitting the signal to drivers that are best able to deal with that portion of the signal. The low end to a bass driver and the mids to a midrange driver etc. The crossover(s) you use will need to be right. I don't see much benefit of sending each pickup to a different amp if you're trying to get the "best and cleanest" sound.
[/quote]

This. Unless you wanted to di or creatively effect one of the pick ups output then it could be a cool feature.

I'd suspect that it'd only otherwise create unpredictable results, if your objective were fidelity.

[synaesthesia]

If you take a signal, split the frequencies and amplify those spilt bands, that would be bi-amping.
If you take a signal out of each pickup in a 2 pickup instrument, and amplify those signals, that would be dual mono amplification.


With bi-amping, any phase cancellations occur as you mix the pickups. The audio system, one assumes, is a phase coherent one. You can feed the top or low end signal to compression, modulation or whatever to a consequential benefit of retaining low, controlling dynamics, etc etc etc

With dual mono, if depends, - what amps you use, and how you blend them, where you place them. Some bass players who do this mix amps, and you net result is rather unpredicatable.

Edited November 15, 2013 by synaesthesia

[DiMarco]

My amp is an old trace elliot rah600smx, which has two output stages with a lot of options. I have been testing things using a 410 and 115 cabinet. Crossover frequency can be set anywhere between 250hz and 1khz.

Ended up running the amp in dual mono mode and skipping the crossover section completely. Crossed at any freq over the sound was simply horrible.

Todays 2x10 and 4x10 cabs are tuned at what, 40hz? There is no need for using any form of corossover anymore.

You could split the signal and run one pickup through a bass stack and the other through a guitar stack with crunch/overdrive though. That rocks!

[molan]

I experimented with bi-amping for a while but didn't really like the results. I was using a simple 1x15 for the lows and a 2x10 with horn for the highs.

Both were designed for full range and I'm sure this was having quite a major effect on the overall tone because they weren't specifically designed to deliver deep lows and sparkly highs.

Overall I felt the core tone when bi-amped was a bit cleaner sounding but it lacked depth and bite. I'm sure it would be different with bespoke cabs though.

I've also seen someone experimenting with different amps and cabs per pickup on a Sheehan Attitude.

That was great fun. I think we ran the clean signal into a Carvin 2000w head and then into a Bag End 2x12. This is very deep and clear sounding combination.

The second channel went into an Ampeg valve head and matching 4x10. This was set up to deliver loads of grit and grind.

The combination sounded just huge!

Unfortunately I think you'd need a roadie (or two!) to shift all that gear around though

[jhk]

[i][b]My Eden WT600[/b][/i] gives me 2 x 300 watts per side ,also has variable crossover on board ,in smaller gig situations it gives me a very Hi-Fi sound............................................................this I feel would be a better option than separate pickup `amping`

hope this helps

[JPJ]

To get the best from bi-amping, you really need cabinets designed for the two different frequency groups. Simple 2x10 1x15 commercial cabs won't cut it imho.

I experimented with bi-amping and concluded that the added gear and complexity wasn't worth it for the almost indistinguishable improvement in 'tone'. That said, our PA is bi-amped, using dedicated sub's and mid/tops (not the best by far, but good enough) and with a bit of careful eq'ing on the desk, I can get a massive punchy bass sound FOH that sits nicely in the mix, leaving my back line as a personal monitor. But for the majority of our gigs, even this is overkill as the back line is more than sufficient for FOH duties in the Dog & Sproat and other such venues that I don't bother putting my bass or the guitards through the PA.

[Marvin]

Billy Sheehan (as already alluded to by Molan) splits has a different signal path for his neck and split coil pickups.

He uses pretty much off the shelve gear as well. The neck pick up he puts through a Hartke LH1000 into a Hartke AK115, this is for his LOW end. The split coil goes through a Hartke HA5500 into a Hartke AK410 for his high end, distortion and other stuff.

Sounds pretty good to me

[Spike Vincent]

I've used the bi amp facilities on the various Peavey amps I've owned in the past, and it did offer a broader sound, and more importantly a better spread of the sound. I don't do it any more because I got fed up ( by which I mean the rest of the band got fed up) of carting round extra cabs

[BigRedX]

In the days when I used a lot more effects than I do now, I had a bi-amped system built around a Peavey Bassfex and a big stereo power amp. This allowed me to do things like apply chorus to the top end of the signal only or have different amounts of distortion on each part of the signal which allowed me to use much more extreme effects settings without loosing the clarity and bottom-end heft of the bass.

On stage I used a modified 1x15 cab for the bottom end, and a specially built 2x8 cab (based on a guitar combo) for the top. This worked very well for monitoring as the top end cab was light enough to go above the amp rack and therefore was level with my head. I also ran separate top and bottom DIs for the PA which usually required a bit of explanation for the sound engineer as the naturally the bottom end signal was quite a bit "hotter" than the top and if they tried to match levels it would produce a horrible clanky sound through the PA. I always told them to set the level on the low channel and then use the same gain setting on the high and everything would sound good and it did.

[Phil Starr]

You would be doing two entirely different things for different reasons and you would need different speakers, at least, to achieve either.

Taking a mono signal and using a crossover is about sending the signal to more capable speakers. Bass needs a big heavy cone, a long coil, high power handling,a particular magnet design and so on. Highs need a small cone for dispersion, lighter so it moves quicker, excursion isn't a problem so you can make the coil shorter and the speaker more efficient (louder) so saving on power handling. This will usually give a cleaner sound all round and if you like the sound of DI'd bass from a stack it could be the way to go. Another alternative might be to use a guitar speaker to give you a desired distorted sound but protected from the bass with a 100Hz crossover and then to fill in the lows with a sub below 100Hz. but essentially most people would go this route to get a cleaner sound. Having said that a better way of doing this technically is just to DI and use the PA sound and set up monitors on-stage. your problem here will be finding someone who makes a really good 'satelite' top for a bass.

Feeding two signals to two stacks is a bit odd. As Synaesthesia (nice to see the dipthong) said the joy of twin pup's is blending them to get phase cancellations or 'mid scoop' and you'd lose this capability for something less predictable by separating the pups output. What you would gain is having two stacks with different sounds so you could use either or both during a gig for different songs and get a range of sounds you couldn't get otherwise by 'blending' the stacks. It wouldn't matter that this is unpredictable because you could hear the results. The trouble of this for me is that I would probably not want to feed the two stacks from different pups.

The old way of splitting signals and feeding to a 1x15 and 2x10 makes no sense, unless you want that particular old school sound, as modern drivers are so much more capable. You really couldn't get decent power handling and bass from anything with high frequencies back then.

If you want a super-clean on-stage sound then go for the crossover. You might need to look to unconventional speakers though. Barefaced sub with Phil Jones tops?

If you want to try splitting the pup's find a fellow bassist who fancies some experimenting and try his stack/combo with yours in various combinations rather than spending a fortune on extra amps and speakers.

[jazzyvee]

I've been trying this for a couple of weeks now, only at home though, and it's quite difficult hear a significant difference in sound in an average living room so I'm going to try it out on my next non reggae gig and hear what the difference is. What seemed to give me the clearest sound either in mono or "dual mono"at home was a HF output from the crossover into a roland JC120 guitar amp. That seemed to give me great clarity as long as I didn't add too much top end or overload the amp.

So still more experimenting to do.