Connecting a bass speaker to a guitar amp

[JonO)))]

I own a (FMIC-made) T50C, and a while ago I built a couple of 112 extension cabs to run it at 4.3 ohms (three 16 ohm speakers).

Whilst I normally play guitar, I recently got a great deal on a bass guitar and for economic reasons alone I hope to play my bass through the T50C.

I have read that it is perfectly safe to play a bass guitar through a guitar amp, except that at high volumes this may damage the speaker (apparently guitar speakers are not designed to accommodate bass frequencies, and can tear as a result of the distortion caused).

Can someone therefore please tell me whether I can simply replace the G12T 75 speakers in one of my extension cabs with a 12" bass speaker, and run the amp through that cab by plugging the cab into the main speaker input on the amp (not the extension speaker input)?

The T50C allows you to switch the impedance between 16/8/4 ohms, therefore I am guessing I could run either a 8 or 4 ohm speaker?

If I am right in the above, can anyone recommend a good speaker? I would have preferred a 15", however that would require a new baffle...

[HRobert]

As long as the impedence is matched to the amp, you should have no problems with using a bass speaker.  I'm into 15" JBL's for keyboards and bass and cannot suggest a good 12" bass speaker.  Perhaps Celestion, Jensen, or some other company makes one...or maybe someone can suggest a company that has a good 12" neo magnet speaker that would work.  If you are using a lot of volume, I would suggest more than one 12" bass speaker to handle the load.

[warandhairstyle]

bass cabs and guitar cabs are often designed differently, with different porting and internal air volume.  simply switching from a guitar speaker to a bass speaker may cause the bass speaker to not function correctly (due to the dimensions/porting of the cab) which could lead to more problems.  Using a guitar AMP for bass is just fine, if you like the tone, but I'd recommend using a cab designed for bass if you're going to be playing loud.

[Isaac]

I see no insoluble problems.

What is the internal volume of the cabinet you want to put the bass driver into? I'm assuming that it's a sealed cabinet. Please correct me if I'm wrong.

Assuming an internal volume of about 2.5 ft^3, the Eminence Basslite S2012 should work well, as would a Delta 12. I'm sure there are many more that would be fine.

[pickinatit]

I see no insoluble problems.

What is the internal volume of the cabinet you want to put the bass driver into? I'm assuming that it's a sealed cabinet. Please correct me if I'm wrong.

Assuming an internal volume of about 2.5 ft^3, the Eminence Basslite S2012 should work well, as would a Delta 12. I'm sure there are many more that would be fine.

If I'm not mistaken,  my  Avatar 212Neo has Eminence Delta Light speakers in it and I really like the tone a lot.

[Isaac]

That's a ported cabinet, though, isn't it? Makes a bit of difference on the low end, though the midrange and treble characteristics would be the same. I'm sure that would be a fine driver for him, too.

Edit to add: The Eminence DELTALITE-II 2512 sims out nicely in a 2.5 ft^3 sealed cabinet.

[JonO)))]

Thanks very much for all of your feedback! It looks like I may be safe!

By my calculations, my cabinets are 2.84 cubic feet in volume, and they are sealed.

There are a number of 12" speakers on the market, however they are invariably available in a variety of wattages. Compare, for example, the Eminence Basslite S2012 150W Bass Speaker with the Celestion Truvox 1225e 300W Raw Frame Speaker and the Eminence Delta 12LFA 500W PA Speaker.

Here is a very elementary question then: what is the difference between speakers with different wattages? Is it true, for example, that the higher the watts, the bassier the sound?

Thanks again for your insight.

[mckinnon audio]

  Hi there,the wattage rating tells you how much power the spkr.can handle,has no bearing on tone.The thing you have to watch out for is frequency response.Some high power P.A. bass/sub drivers have a very narrow bandwidth,some go from 20Hz to 250 Hz,great for subs in a P.A.,not so great for a bass guitar cab.,you'll have to add treble for days to get lots of upper mids and bite,if your rig isn't biamped.M.I.(musical instrument) bass drivers tend to have an extended hi end response,sometimes up as far as 2 Khz,so they work better in a single spkr. situation,but usually have a lower power rating than P.A. drivers.Hope this is of some help,good luck,Mel.

[EdBass]

Here is a very elementary question then: what is the difference between speakers with different wattages? Is it true, for example, that the higher the watts, the bassier the sound?

Maybe yes, maybe no, but there is no direct correlation. It depends on the spec of the particular driver.
Probably the most consistant thing would be that generally the higher the power handling capacity, the less efficient/sensitive the driver is, and often SR specific drivers have more narrow response curves, but even that isn't written in stone.
Using a T50 for power, you don't really need a big burly woofer. A 300 watt or 500 watt driver is big time overkill, it won't hurt (except possibly your volume and/or frequency range), but a lower powered driver would suffice, save you some dinero, and work just fine. Maybe even better.

[EdBass]

  Hi there,the wattage rating tells you how much power the spkr.can handle,has no bearing on tone.The thing you have to watch out for is frequency response.Some high power P.A. bass/sub drivers have a very narrow bandwidth,some go from 20Hz to 250 Hz,great for subs in a P.A.,not so great for a bass guitar cab.,you'll have to add treble for days to get lots of upper mids and bite,if your rig isn't biamped.M.I.(musical instrument) bass drivers tend to have an extended hi end response,sometimes up as far as 2 Khz,so they work better in a single spkr. situation,but usually have a lower power rating than P.A. drivers.Hope this is of some help,good luck,Mel.

Oops, I was typing when this^^ was posted; so...
What Mel said, and sorry for the duplication!

[Isaac]

One more thing: three 16 ohm speakers in parallel is 5.3 ohms, not 4.3 ohms.

[JonO)))]

Thanks again guys - I'm extremely grateful!

[JonO)))]

Further to my earlier queries, I was subsequently advised that I would be better off simply buying a bass amplifier and cabinet rather than changing the speakers in one of my 112 cabinets.

To that end, happily I was able to buy a cheap bass 410 (with indeterminate Eminence speakers) on ebay, with a view to one day buying a cheap bass amp. The quad, I am told, is 300W rated at 8 Ohms (the seller claims he bough it new).

Since I have yet to get hold of a bass amp, and the T50C switches down to 4 Ohms, here is an impedance question based on the fact that I understand two 16 Ohm speakers run together rate at 8 Ohms, and that "if you run a cable from the amp to a speaker that has two jacks, and run another cable from the second jack on the first speaker to a second speaker, it is still a parallel connection":

Can I run my onboard 16 Ohm speaker, and then (from the external jack) run one of my 16 Ohm extension cabs in series with the 8 Ohm bass quad - at a total impedance of 4 Ohms?

PS. I have googled most of this information, but I just don't understand electronics!

[Isaac]

Yes, but it won't be in series, just daisy-chained.