QSC PC12 FOR A BASS AMP?

[Gary Usinger]

Aloha All,
New to the forum. I am getting a QSC PC12 powered amp to act as both a monitor when we are playing in a situation where we have full power, and my wife can use her 4-10 ETC rig. Then when she needs, use the same powered speaker along with a lithium power supply for a bass amp.

I looked all over for a battery powered bass amp and they all sucked. Either not loud enough or distorted when you did turn them up.

So I think this will work. The QSC actually has a sub setting, so I think with a 1000 watt amp and speaker, she will be good to go as long as the lithium power source can work with the QSC.

I also thought that she can use her ETC head along with the 12" speaker if it is possible to bypass the amp part of the QSC.

Any advice or auggestions are greatly appreciated.

Thanks,
Gary

 

[Gary Usinger]

Sorry, meant to say QSC "CP" not "PC"

Anyway, let me know what you think.

Thanks!

 

[seamonkey]

Here's a pure sine wave inverter that would probably power the CP
RYOBI 300-Watt Powered Inverter Generator for 40-Volt Battery-RYi300BG - The Home Depot
Get some spare batteries in case you need to change one during a gig.

The CP is 1000w "peak" it's probably going to consume around 50w normally.

HD is good about returns if there are any problems and the batteries come with a 3 year warranty. Which is a longer warranty than most.

 

[Gary Usinger]

Thanks seamonkey! I was looking around for power supplies, and because we live in Hawaii, could not get Amazon to send one here. If Kona Home Depot has them, then that is great. I will get one tomorrow. I can try it out on the TC BF 550 that we have to see if it works with that amp. Do you think it will power that amp? Is there a problem with using a 300 watt powered inverter on a 550 watt power amp. The QSC has a 1000 watt amp in it I was also thinking about getting a smaller speaker cab to use with the TC BF 550 like the 2-8" TC cab or the 10" Trace Elliot, but both of those are in the 200 to 300 watt neighborhood, and don't know if that is a problem with a 550 watt amp. It would be nice to have a lighter cab for my wife to use for practice and use the 4-10 for shows.

Thanks again,
Gary

 

[Redbrangus]

I also thought that she can use her ETC head along with the 12" speaker if it is possible to bypass the amp part of the QSC.

I wouldn't count on this concept being viable. The manufacturer makes no provision for it, and besides, the success of this type of design depends on the close coupling of the speaker/amp/processing combination; the speaker alone isn't likely to provide particularly stellar performance. Have you actually demo'ed playing bass through the powered speaker to be sure it will be adequate for that application?

 

[abarson]

I know that there are others here who use powered speakers and QSC is reputable. I don't think the sub setting would be right as you would be cutting out lots of the instrument's spectrum. I don't think there is a way to bypass the integrated QSC amp, and if you could what would be the point?
You should contact QSC about current draw in the lithium supply scenario.
I can't find any reference to a bass amp company called ETC.

 

[seamonkey]

The QSC is 1000w "PEAK". It's not a continuous 1000w. There are two 500w Peak amps in it. One 500W for the lows, and one 500w for the highs. You'll never use the full 500w for the highs. It's unfortunate that QSC advertises is as 1000w as it never puts out all that power. If you're cranking the think it will probably produce 600w peak (500w peak lows, 100w peak highs at most) or 300w continuous. Normal draw will be somewhat lower. Like 1/8th of 300w.

For running it with a 300w pure sine inverter. The inverter works like a circuit breaker. If you draw more than 300W for a period of time then the circuit breaker opens. You'll have to wait a while before you can operate again. Bigger inverter could be better, but then heavier, and need more batteries.

300w inverter may work fine if you don't constantly crank everything. If you're going to crank then you can look for a pro-grade inverter. Milwaukee makes one that takes even bigger batteries. These things get as big as small generators. Many of them you can't swap batteries. They are more of a emergency power suppy.

Other higher powered inverters are "modified sine waves". it's possible they may have a problem depends on the gear. They are cheaper per the watts they put out. I'd expect one would work with the QSC but you'd have to try it.
People run power tools, computers, audio players off the modified inverters without problems. They may work.

 

[Redbrangus]

The LF amp is 800 watts, the HF amp is 200. The 'sub' setting is to optimize the speaker's performance when it's used with a sub--it other words, it will reduce the extreme LF response...a sort of tacit admission that the performance in the low end might be somewhat lacking, which is to be expected in a such a small enclosure.

The QSC web site claims about 75 watts power consumption at 1/8th power for this device. This implies a max power consumption of about 600 watts; the inverter supplying the amp will need to be able to safely provide that much power to prevent the circuit breaker from kicking in on a sudden peak, even if the overall level operating level is considerably lower.

 

[seamonkey]

The LF amp is 800 watts, the HF amp is 200. The 'sub' setting is to optimize the speaker's performance when it's used with a sub--it other words, it will reduce the extreme LF response...a sort of tacit admission that the performance in the low end might be somewhat lacking, which is to be expected in a such a small enclosure.

The QSC web site claims about 75 watts power consumption at 1/8th power for this device. This implies a max power consumption of about 600 watts; the inverter supplying the amp will need to be able to safely provide that much power to prevent the circuit breaker from kicking in on a sudden peak, even if the overall level operating level is considerably lower.

I'm glad they fixed their ratings from older models to better balance the amps.
Class-D is still better at drawing less power and lower volume levels. A 300w pure sine might work for moderate volume. I doubt QSC has info on it, and they probably don't test it.
One way to know for sure is to try it. If it doesn't there are higher power inverters but you get up to small generator sizes quick. New small generators can be fairly quiet. Not totally, but may be usable quiet. And you have to check the sine wave output.

 

[Gary Usinger]

Aloha All,

Thanks for all of the info and attention. I am trying to figure this out, and hoping I don't blow anything up. As I understand it, at the worst, it just won't work and the circuit breaker will kick in. Worth a try. I am now thinking that I could forget about the QSC, and just use the TC head (sorry about the earlier reference to "ETC" - I was confusing my lighting with my music).

So anyway, the TC BF 550 bass head that we have says that it runs at 200 watts at 1/8 power. I can get either a 200 watt TC 2 - 8" cab, or I was looking at a Trace Elliot with 1 10" speaker that is a 300 watt one. There are some other options out there like an Ampeg SVT-210AV (200w) and another Trace Elliot with 2 - 8" speakers that is a 400 watt one.

The reason I am thinking about the bass cab idea is that my wife wants a lighter weight option than her TC 4-10, so I am just trying to figure out if the QSC will sound as good as the TC BF 550 with the TC cab or the Trace Elliot options.

Thanks all for the replies.

 

[Redbrangus]

I think any of the 4 cabs you listed, coupled with that head, would make a better bass rig than the CP12. Noticeably so, IMHO. My pick is the Elf 2x8 if you afford it, but it IS the most expensive one of the bunch. I think it's probably also the heaviest.

Edit: I edited this to reflect the fact that you listed 4 cabs. All better choices than the QSC.

 

[Remoman]

Here's a review of using a QSC powered PA for a bass amp from a buddy of mine. Might help in your decision.

 

[Gary Usinger]

Here's a pure sine wave inverter that would probably power the CP
RYOBI 300-Watt Powered Inverter Generator for 40-Volt Battery-RYi300BG - The Home Depot
Get some spare batteries in case you need to change one during a gig.

The CP is 1000w "peak" it's probably going to consume around 50w normally.

HD is good about returns if there are any problems and the batteries come with a 3 year warranty. Which is a longer warranty than most.

SEAMONKEY - new to forum and not sure this will get to you, but wanted to tkank you for your advice about the 300 watt inverter from HOME DEPOT and let you know that I passed on using the QSC amp and went with the TC 550 that I already have running it at 50% along with a light weight Trace Elliot 10" 300 watt cab, and the inverter powered the amp loud enough to use with a drummer and the rest of the band for 4 to 5 hours on one charge. I am going to get a spare battery and should be good to go. Thanks for your suggestion.