Using active PA cabs as backline?

[John_P]

I've got a few bass gigs coming up and I was looking to buy an amp - typical small/medium functions and parties.
I have a few active cabs from my PA - db opera 415 and thought I could use one of those with a preamp - I've got an atomic amplifire that would do.

Any thoughts or am I going to sound thin and I would be better just buying a dedicated bass amp?

[Bill Fitzmaurice]

While it's loaded with a 15 bass extension is as much a property of the cab size as the driver size, and that's a very small cab. It might work, but I'd make sure of it before trying to gig with it.

[Dan Dare]

Need to try it and see. Could work, especially if you don't need massive volume. Use a decent preamp.

[Phil Starr]

There's three things to consider,

will you like the sound? it's going to be cleaner than a bass amp, not everyone likes that.

will there be enough bass? If the cab is too small or the bass driver limited in excursion it could wimp out at high bass levels.

Will it survive the treatment? Related to the above it will depend upon how much bass you call upon it to give. Quality PA units will be fine as the bass drivers will be designed to take the bass. So will any with DSP built in, which will protect the speaker by turning down your peaks for you.

[stingrayPete1977]

I think it will sound just fine with a preamp, nowt wrong with those cabs. Plenty of good sounding bands out there where those pa tops will be what the audience hears.

[Bill Fitzmaurice]

[quote name='stingrayPete1977' timestamp='1481285650' post='3191198']
Plenty of good sounding bands out there where those pa tops will be what the audience hears.
[/quote]If they're all the audience hears the lows will be weak. They're small, so they won't have much in the lows best case, and up on a pole where they need to be as PA mains is the worst case for lows, as they won't get boundary reinforcement from the floor. Used with subs handling the lows as they should be they'd be fine, but that scenario isn't what the OP is dealing with.

[John_P]

Thanks chaps, when I used to gig these as the PA, they were paired with an active sub on each side so they didn't needed to push any lows. I've seen plenty of cheap amps so I'm leaving these for occasional vocal monitor duties.

[stingrayPete1977]

[quote name='Bill Fitzmaurice' timestamp='1481289662' post='3191255']
If they're all the audience hears the lows will be weak. They're small, so they won't have much in the lows best case, and up on a pole where they need to be as PA mains is the worst case for lows, as they won't get boundary reinforcement from the floor. Used with subs handling the lows as they should be they'd be fine, but that scenario isn't what the OP is dealing with.
[/quote]

If it's small/medium functions I presume there will be a foh to go with the amp, should be able to handle purely monitoring duties, let the PA do the real work?

[Bill Fitzmaurice]

[quote name='stingrayPete1977' timestamp='1481724564' post='3194568']
If it's small/medium functions I presume there will be a foh to go with the amp
[/quote]One thing I learned long ago is that you can never assume that PA will be adequate, if there's any at all.

[stingrayPete1977]

[quote name='Bill Fitzmaurice' timestamp='1481730399' post='3194625']
One thing I learned long ago is that you can never assume that PA will be adequate, if there's any at all.
[/quote]

Again I'm working on the basis that the OP will be familiar with the PA at the gigs if it's function stuff?

[Phil Starr]

[quote name='Bill Fitzmaurice' timestamp='1481730399' post='3194625']
One thing I learned long ago is that you can never assume that PA will be adequate, if there's any at all.
[/quote]Most bands in the UK carry their own PA Bill, it isn't universal but I've only been to a couple of venues with their own PA. I gather from other forums that in the USA it is far more normal to use a house PA. Is that true?

[Bill Fitzmaurice]

The rule of thumb in the US is that you're expected to provide PA. I doubt that one venue in fifty has a house system. When I was touring I played in better than average rooms, made a reasonable living, and as best I can recall over a three year period playing in perhaps a hundred different rooms a total of two had PA.

[Phil Starr]

Right, so little difference to my experience then. Thanks.

[Passinwind]

[quote name='Phil Starr' timestamp='1481788893' post='3195088']
Right, so little difference to my experience then. Thanks.
[/quote]

Just within 5-6 miles of me there are at least eight venues that have house systems, not counting summer festivals, which nearly always have PA support.. This, for a population of right around 10,000 people between three towns.When I lived on the east coast it was a lot closer to what Bill describes though. So as usual, I'd say it just depends.