Power amp

[Zooberwerx]

When running each cab in a channel I hear the limiter and I don't like. I usually run both cabs in parallel, bridge mode.
Sorry, I think I haven't explained myself properly.

I've heard this complaint before as it applies to the "00" series. It apparently works but a little too-well.

Riis

 

[agedhorse]

I think there is something else going on here. Either reaching the limits of the speakers, or a misapplication of the technology.

 

[Wasnex]

I have a proper speakon cable for bridge.
So, what I can read on all your answers is that I am not going to get better volume feel with a dedicated bass amp 400w@8ohm with a dedicated bass limiter than my Crown in bridge mode.

I usually get enough volume from my rig, but when the venue has bad acoustics, I change the Eq and have fear of blowing the cabs, and because of that I don't turn up the volume. Maybe, with a 400w@8ohm I would feel more confident.

FYI, my cabs are a GreenBoy F112 450w@8ohm and a Barefaced BB3 800W@8ohm.

AFAIK the F112 uses a 3012LF woofer. Sensitivity for the 3012LF is listed as 95.5dB 1W/1m, which is on the low range. A pair would give you about 98.5dB 1W/1m (much better IMHO).

If you are using one cab at 300W then calculated SPL = ~120.3dB

In bridge mode at 450W the calculated SPL = ~122dB

This is not a lot of headroom if you are playing with a loud drummer in a room with crappy acoustics.

If you search, I think you will find others who were surprised and disappointed with the headroom limits of a single F112 or 12/6.

Two cabs with the amp in dual mono (300W per cab) = ~126.3dB

Two cabs with the amp bridges (450W per cab) = ~128dB

I find that a rig capable of at least 124dB usually meets my needs, so both of these combinations would likely be enough for me.

 

[Diegombass]

Today, outdoors gig, loud mates at drums and guitars, PA just for voices, flute, sax and drum kick.
I can hear myself beautifully loud. Two cabs, bridged, Crown knob at eleven. No fear...

 

[tom-g]

AFAIK the F112 uses a 3012LF woofer. Sensitivity for the 3012LF is listed as 95.5dB 1W/1m, which is on the low range. A pair would give you about 98.5dB 1W/1m (much better IMHO).

If you are using one cab at 300W then calculated SPL = ~120.3dB

In bridge mode at 450W the calculated SPL = ~122dB

This is not a lot of headroom if you are playing with a loud drummer in a room with crappy acoustics.

If you search, I think you will find others who were surprised and disappointed with the headroom limits of a single F112 or 12/6.

Two cabs with the amp in dual mono (300W per cab) = ~126.3dB

Two cabs with the amp bridges (450W per cab) = ~128dB

I find that a rig capable of at least 124dB usually meets my needs, so both of these combinations would likely be enough for me.

What do mean by headroom in this context? I alway thought it‘s the power available that I don‘t need. So if you mean it in that context, it‘s a moot point, as it‘s not needed.
Anyway, I have not come across any posts saying an F112 is not performing as expected or they were disappointed by its performance.

 

[dbase]

Instead of all these calculations, It would be much easier to just buy a Mesa TT800 bass amp w/ Subway twin 15's? just sayin.

 

[paskisti]

Today, outdoors gig, loud mates at drums and guitars, PA just for voices, flute, sax and drum kick.
I can hear myself beautifully loud. Two cabs, bridged, Crown knob at eleven. No fear...

In Bridged mode you really should hear yourself good enough if cabs do their part. I'm not familiar of F112 but even they are better than average 112, be careful not to send full 1500W into them. And I can fully understand you are running out of steam when using amp in stereo mode. @Wasnex wrote very well that F112 is not sensitive cab and we can see that it needs more power than some other bass cabs in market to produce similar sound pressure levels. Note also that you'll make 2,5 times the power in bridged mode to same cabs than in stereo mode. That headroom keeps you smiling as long as your speakers are healthy.

 

[Diegombass]

I have made a decision: I will not pass 12 o'clock plus 2 steps of the volume in bridge mode. In my Hx Effects some parallel compression when needed as always; a booster +6dB when needed; 18dB of gain and line output to drive the input of my Crown at 1.4v; and I have put a limiter at the end of the chain, fine calibrated to have a lot of headroom until I need more volume.
I think that "the problem" (and the gift) is my bass and not using an always on compressor (nor a typical bass preamp with comp or limiter integrated in the sound): it can sound very very dynamic.

I have no gigs with this rig for a month. I will tell you my impressions when I try it.

Thanks for your attention.

 

[DonaldR]

Have you tried the ZeroAmp model (Tech21 BDDI) on your HX Effects? This will give you a preamp to start with, and some "natural" compression.

 

[Diegombass]

Have you tried the ZeroAmp model (Tech21 BDDI) on your HX Effects? This will give you a preamp to start with, and some "natural" compression.

Yes, I am using it lately. I like to use it when I play standard rock pop, but it happens rarely.
Thank

 

[agedhorse]

Knob position doesn’t limit the power, it just increases the drive level required to reach rated power.

 

[paskisti]

Knob position doesn’t limit the power, it just increases the drive level required to reach rated power.

This is important to understand with separate power amps. It limits the input signal but it gets high enough you can still get full power to speakers. Different topic is if it can happen with used preamp.

 

[Diegombass]

Yes, I know it, thanks.
The limiter is last in my chain. Before that, there is EQ, gain, booster, compressor, overdrive, octaves, chorus, filter, delay, reverb...

 

[Diegombass]

Yes, I know it, thanks.
The limiter is last in my chain. Before that, there is EQ, gain, booster, compressor, overdrive, octaves, chorus, filter, delay, reverb...

I mean, the volume mods are before limiter