Pre-Amp -> Power Amp... is a Bass Amplifier even needed?

tylerwylie · #1 11-21-2010, 04:44 PM

If I'm running something like the Tech 21 Sansamp RPM or the Bass Driver DI, could I run that into a power amp and hook that up to a cab or two and just bypass having a bass amp altogether? I was also looking at Genz Benz rigs but it seems this route might get me a good solid sound, a good chunk of power and at a very affordable and attractive price.

I'd probably end up running a GEB-7 Bass EQ and an LMB-3 Limiter/Enhancer as well. I plan on playing a Bongo 6, Fender Jazz, and ESP LTD B404 SM through this rig so having a transparent amplifier that doesn't color the tone past my Bass Driver DI would be ideal.

thudfromafar · #2 11-21-2010, 04:47 PM

Yeah, look into a poweramp with onboard DSP such as the crown XTI or XLS drivecore. That way you can add a high-pass filter (which most bass heads have built-in) to protect your speakers.

BillyIVbass · #3 11-21-2010, 05:02 PM

Eh $150ish for a preamp then $300ish for power amp. Sometimes you need a DI to get a hot enough signal. $450 can buy a decent amp these days. Less things to plug in wrong. Personally I see an amp as much simpler, but hey, that's just me.

Lowtonejoe · #4 11-21-2010, 05:15 PM

Quote:

Originally Posted by tylerwylie

If I'm running something like the Tech 21 Sansamp RPM or the Bass Driver DI, could I run that into a power amp and hook that up to a cab or two and just bypass having a bass amp altogether? I was also looking at Genz Benz rigs but it seems this route might get me a good solid sound, a good chunk of power and at a very affordable and attractive price.

I'd probably end up running a GEB-7 Bass EQ and an LMB-3 Limiter/Enhancer as well. I plan on playing a Bongo 6, Fender Jazz, and ESP LTD B404 SM through this rig so having a transparent amplifier that doesn't color the tone past my Bass Driver DI would be ideal.

Yes.

In the pic below I am playing my Thumb into a Sansamp PBDDI (on top of the amp) into a QSC RMX850 into my Bag End S15-CUS.

Works great, sounds great!

Joe.

JimmyM · #5 11-21-2010, 05:19 PM

Quote:

Originally Posted by Lowtonejoe

Yes.

In the pic below I am playing my Thumb into a Sansamp PBDDI (on top of the amp) into a QSC RMX850 into my Bag End S15-CUS.

Works great, sounds great!

Joe.

and the lighting was perfect

Lowtonejoe · #6 11-21-2010, 05:24 PM

Quote:

Originally Posted by JimmyM

and the lighting was perfect

Yes!

Darned hot though.

Joe.

Mr. Foxen · #7 11-21-2010, 05:29 PM

Graphic demonstration that a head isn''t needed at all.

Art Araya · #8 11-21-2010, 05:35 PM

Quote:

Yeah, look into a poweramp with onboard DSP such as the crown XTI or XLS drivecore. That way you can add a high-pass filter (which most bass heads have built-in) to protect your speakers.

Could someone explain this to me? I don't know what a high-pass filter is or why it is needed in a power amp.

I use a Carvin DCM2000 power amp. Do you know if this power amp provides that protection?

St Drogo · #9 11-21-2010, 05:35 PM

EHX have this pedal sized poweramp out that you could put on a pedalboard; the 44 magnun. They claim it works well on bas and other instruments, though it is made for guitar. It seems, if I understand it correctly, you can just plug in some effects on on one side, and plug the magnun into a cab on the other side and that works.

No idea how it sounds, though (Anyone got clips?). And it runs at 44 watts. So. Yeah. But maybe worthwile to look into.

JimmyM · #10 11-21-2010, 05:38 PM

i'd try before i buy. a lot of times those things are voiced for guitar and they don't have the low end you need on bass.

audiomitch · #11 11-21-2010, 05:41 PM

Yes. I've even used a Boss ME-50B pedal board straight in to a power amp. It worked great.

Bass_Pounder · #12 11-21-2010, 05:48 PM

Quote:

Originally Posted by Art Araya

Could someone explain this to me? I don't know what a high-pass filter is or why it is needed in a power amp.

I use a Carvin DCM2000 power amp. Do you know if this power amp provides that protection?

A HPF (also known as a rumble filter) cuts off all frequencies below a set point (usually in the 20 - 40 hz range) to eliminate subsonic frequencies.

I used to use a DCM1500, and don't remember the Carvin's having them.

ETA - A quick look at the Carvins manuals shows that they did offer a low cut switch on the 2500 and up amp - not on the DCM2000 and below

mowburger · #13 11-21-2010, 05:51 PM

Anyone know if the BDDI has enough ooomph to push a poweramp to LOUD volume? I've been thinking of going BDDI as pre into a poweramp, is it better to use the XLR out or 1/4" srry for hijack

JimmyM · #14 11-21-2010, 06:03 PM

Quote:

Originally Posted by mowburger

Anyone know if the BDDI has enough ooomph to push a poweramp to LOUD volume? I've been thinking of going BDDI as pre into a poweramp, is it better to use the XLR out or 1/4" srry for hijack

it does, and i'd use the 1/4" to the power amp and the xlr to go to the pa.

oddio · #15 11-21-2010, 06:47 PM

Many power amps have HPF built in already. Of course, it depends on the brand/model... for example on QSC PLX models the frequency is selectable; Crest CA series has an automatic subsonic filtering built in, and so forth. DOn't know about Carvin.

Art Araya · #16 11-21-2010, 07:00 PM

Does not having a HPF truly endanger a cab?

I guess I'm asking of a power amp used for bass guitar purposes must have a HPF?

Lowtonejoe · #17 11-21-2010, 07:09 PM

Quote:

Originally Posted by Art Araya

Does not having a HPF truly endanger a cab?

I guess I'm asking of a power amp used for bass guitar purposes must have a HPF?

No it does not...as long as you pay attention to your eq.

If you dial in lots of lows with no cutoff then you may have a problem. Just be smart. It's like anything else in this world, abuse it and it will wear out or break sooner than it's projected life expectancy.

Joe.

timbledum · #18 11-21-2010, 07:11 PM

Quote:

Originally Posted by Art Araya

Does not having a HPF truly endanger a cab?

I guess I'm asking of a power amp used for bass guitar purposes must have a HPF?

Well you don't reeeeeaaaally need a HPF in the fact that your cab will probably won't be overdriven and you probably won't have many audible issues. However those inaudible low frequencies take a lot of power to drive, and by cutting them out it is likely that you would be able to get more audible volume out of the amp. A prime example of this is the 4/5 string button on gk amps. As far as I know, this button shifts the high pass from the old-school traditional pass frequency from the days where everyone had a four string and watts were expensive to a lower pass for relatively new 5 strings.

What I'm trying to say that beside the risk of driving your cab and getting muffly sub-sonic rumble, your amp will be inefficient and consequently it is likely that you will need more watts for the same bang.

tylerwylie · #19 11-21-2010, 09:47 PM

Also how would I fit my effects in if I was using the DI pedal? The effect pedals come after the DI box but that'll be what runs to the PA system? So 1/4" to pedals -> power amp, and XLR -> PA system, would that mean my effects aren't going to be heard in the PA system?

JimmyM · #20 11-21-2010, 10:07 PM

bass > pedals > preamp > xlr to house, 1/4" to power amp. problem solved.