Oh, cool. Anohter can I bass through a guitar amp...

TravTrav · #1 05-11-2011, 10:54 AM

I know this kind of topic has been beat to death, but I can't find the specific information I'm looking for. And I'm hoping you guys could help a brotha out.

I got this RedBear Mk120 (Russian head, tube, 120 watts,etc) for guitar, but it pushes out ridiculous low end. Like, it's borderline stupid. I have it running through a 2x12 mesa recto if that means anything.

Now, I'm pretty positive that 120 watts doesn't cut it for bass. So I was wondering if I were to hook up as many cabs/speakers as possible, could I end up with a decent bass rig?

Or if I ended up doing two 8x10 cabs (or something ridiculous) would the cabs be too underpowered?

Thanks for any insight on this troubling dilemma.

jgriffin · #2 05-11-2011, 11:00 AM

I know that people say that 'watts are watts' but in my experience, even 50w from a tube guitar head was more than enough power to play with two guitars and a hard-hitting drummer, and that was only running through a 2x10.

Ric5 · #3 05-11-2011, 11:00 AM

Pretty much all of the bass amps of the 60s were just guitar amps minus the reverb.

dbhokie · #4 05-11-2011, 11:03 AM

Hooking up more speakers does not increase an amps power at all. It can increase air movement if the speakers are being driven sufficiently.

You need to know more information about the head itself, you can find that on google I am sure.

What ohms is it rated at for what wattage. What ohms are recommended. Ideally you want to get a speaker combination that matches your sine RMS wattage output closest (bit above). This ensures more excursion of the cone, and more air movement, with high quality speakers this will end up being a more pleasant result.

If you just keep adding cabs you are going to f with your impedance and burn your amp out.

A lot of amps can't handle 2 ohm loads well, most amps can handle 4 fine. A good amp should be able to handle 2 fine. If yours can, then the most possible power you could get out of it would be to get a speaker configuration that ends up being 2 ohms.

As far as I know, the only other difference is air movement, so two speakers being pushed all the way, still may not move as much air as four speakers pushing halfway, however if you have four speakers being pushed all the way with decent excursion, then it would tend to "seem" to be more sound because of more air movement. You don't want to grossly under-power low-end speakers all the time, because you want the excursion.

coreyfyfe · #5 05-11-2011, 11:08 AM

Quote:

Originally Posted by TravTrav

Now, I'm pretty positive that 120 watts doesn't cut it for bass. So I was wondering if I were to hook up as many cabs/speakers as possible, could I end up with a decent bass rig?

120 watts from a tube amp into the right number of speakers can be ridiculously loud on any instrument. I used to use an ampeg V4 through an 8x10. Loud as all get out when pushed. Especially if you like a little distortion in your sound.

Quote:

Originally Posted by TravTrav

Or if I ended up doing two 8x10 cabs (or something ridiculous) would the cabs be too underpowered?

There is an FAQ thread I suggest you look though. Short version is if your speakers were going to die from underpowering they'd do it while you had them sitting with no input signal.

will33 · #6 05-11-2011, 11:09 AM

Can hook up all the cabs you want, just make sure the switch on the back is set to the correct ohms. No such thing as underpowering and there are plenty if good sounding 100 watt tube heads for bass. It's guitar speakers that can be damaged by bass, not the amps.

TravTrav · #7 05-11-2011, 11:10 AM

I meant plug in as many cabs as possible. Possible being operating safely.

I really can't find out a whole lot about these amps, except they were manufactured in Russia during the '90s for Gibson and they may be JCM900 copies.

The ouputs on the back are one 16 ohm, one 8 ohm, and two 4 ohm. I'm imagining the 4 ohm happens from running two 8 ohm cabinets (I don't know much about this stuff).

I figured more cabs/speakers you have, the more air moving. Which may no be louder, but more massive? I dunno, loudness and sound is so subjective anyways. But the most extreme combination I could think of was two 8 ohm 8x10's.

Thanks for all the info so far, guys.

TravTrav · #8 05-11-2011, 11:12 AM

Quote:

Originally Posted by coreyfyfe

Short version is if your speakers were going to die from underpowering they'd do it while you had them sitting with no input signal.

So simple. I'll be sure to look through that FAQ. I should've done that first.

dbhokie · #9 05-11-2011, 11:13 AM

There really is such a thing as underpowering speakers. In the high end audiophile world especially. Low frequencies are made by movement, if you hook up a 500 W Sine RMS Speaker to a 50 W head, the excursion will be so low, that you will notice a difference in sound than if that speaker was instead a 75 W Sine RMS Speaker which would be using almost all of its excursion.

You can't damage by underpowering, but you are better off being somewhat in the ballpark of matching rather than having 4000W worth of speakers for a 200 watt head or such.

120 watts is plenty for most any gig too, I mean run a DI if you need more into the PA

My name is Mudd · #10 05-11-2011, 11:14 AM

The sticky is here.

Downunderwonder · #11 05-11-2011, 11:15 AM

Oh dear. It's a tube amp. It can put all its power into whatever ohm loads its power transformer is set up for.

120W is not to be sneezed at if your band isn't overly loud.

Pilgrim · #12 05-11-2011, 11:19 AM

Quote:

Originally Posted by TravTrav

I meant plug in as many cabs as possible. Possible being operating safely.

I really can't find out a whole lot about these amps, except they were manufactured in Russia during the '90s for Gibson and they may be JCM900 copies.

The ouputs on the back are one 16 ohm, one 8 ohm, and two 4 ohm. I'm imagining the 4 ohm happens from running two 8 ohm cabinets (I don't know much about this stuff).

I figured more cabs/speakers you have, the more air moving. Which may no be louder, but more massive? I dunno, loudness and sound is so subjective anyways. But the most extreme combination I could think of was two 8 ohm 8x10's.

Thanks for all the info so far, guys.

Don't just start hooking up cabs, or you can fry the amp by running incorrect impedence. I think you know that, but it bears repeating.

More speaker surface means more apparent loudness - but there's a point where it's kinds ridiculous. A single 4x10 that is **EFFICIENT** powered by a 120W amp can be very loud indeed. You can learn more about speaker efficiency here: Stereo Amplifier Power - Amplifier and Speaker Efficency - Amplifier Power and Speaker Loudness.

A 120W amp isn't going to cover outdoor performances, but if your band is playing at reasonably sane volumes, with a single efficient 4 ohm cab (or perhaps two 8 ohm cabs) it will be plenty loud enough for most interior gigs. I have played many gigs with a Bassman 120 combo using a single 15" speaker.

TravTrav · #13 05-24-2011, 06:46 PM

So.....

What would you duderinos recommend for an efficient 8-ohm 4x10 cabinet?

Preferably something offered at Guitar Center because I want to trade in my Mesa Recto 2x12 towards something.

Pilgrim · #14 05-24-2011, 07:41 PM

Quote:

Originally Posted by TravTrav

So.....

What would you duderinos recommend for an efficient 8-ohm 4x10 cabinet?

Preferably something offered at Guitar Center because I want to trade in my Mesa Recto 2x12 towards something.

Start checking specs online...but you lose a LOT of money when you trade. Sell on Craigslist yourself, then go with cash.

Example: your rig is worth $350-$400. They give you $100-$150 on trade, the rest is profit - while YOU could sell it for $350 yourself. You gain $200-$250.

BigOldHarry · #15 05-24-2011, 07:42 PM

at least it's not another "Why doesn't Metal get respect" thread...

KramerBassFan · #16 05-24-2011, 07:53 PM

It's all about having mids.

If you are willing to have a bit less bass, and boost the mids, you can get by with a surprisingly small amp.

TravTrav · #17 05-24-2011, 08:02 PM

Quote:

Originally Posted by Pilgrim

Start checking specs online...but you lose a LOT of money when you trade. Sell on Craigslist yourself, then go with cash.

Example: your rig is worth $350-$400. They give you $100-$150 on trade, the rest is profit - while YOU could sell it for $350 yourself. You gain $200-$250.

Oh, I know that. I did the CL thing for a while, but I kept on pulling out of offers from people because I wasn't sure if I wanted to sell it. I think everyone within my area is fed up with me.

EDIT: What do you guys think of this cab, Kustom 4x10 tuck and roll: http://seattle.craigslist.org/see/msg/2391024815.html. Either I haven't been looking, but I think that's the first cab I've seen list it's sensitivity. 96db ain't too shabby, if I'm not mistaken....

TravTrav · #18 05-24-2011, 08:03 PM

Quote:

Originally Posted by KramerBassFan

It's all about having mids.

If you are willing to have a bit less bass, and boost the mids, you can get by with a surprisingly small amp.

Oh, yeah. I plan on running my bass quite nasty and dirty. I'm thinking clean headroom is out of the question.

**Staccato** · #19 05-24-2011, 08:10 PM

You've got plenty of watts for the job.

Rule of thumb, bass cab, or bass speakers. My 65w valve amp will drive a full stack without any problem (that's eight 'bass' speakers). You won't see me connect it to a guitar cab/guitar speakers with my bass!

TravTrav · #20 05-26-2011, 09:50 PM

Sorry for not letting this thread die......

BUT, will there be a noticeable volume difference if I were to save up for Traynor YBA200 vs my redbear which is 120 watts (both are tubies)?

I realize that it takes 10 times the watts to double power, and 3db more is actually twice as loud, blah, blah, etc. I do value your guys' bass expertise....