Wattage for extension passive speaker cabinet

[Teak]

Two years back I bought a Carvin AG200 acoustic amplifier that has an output jack for one extension speaker (passive). The Carvin handles up to 200 watts, and the extension is rated for up to 50 watts.

Since Carvin no longer builds extension speakers for the AG200 (a line they also discontinuted), I need to buy another brand.

My question, if I buy a passive speaker that handles up to 20 watts, will that restrict the volume at which I run the system? In other words, if I push the extension up to 20 watts with the Carvin's volume control, will the sound distort beyond that point? The local music store has an Orange Micro Terror (1x8, 8 ohm, 20 watts) that I have already tried at lower volume, but I wonder about playing outdoors where I might want higher volume.

I am assuming that the extension speaker becomes the weaker link if I don't get one that is rated up to 50 watts, or higher.

[mandroid]

read the Carvin manual?, whate the outlet rated for? called them on the phone?

adding more speakers ohm wise lowers the impedance..

so 2 x 16 =8 2x8=4.. at 2 oum you may damage your amp

RTFM is always advisable..




...

[Teak]

So 2 x 8 ohm in parallel equates to 4 ohm overall. Doesn't answer my question.

Thanks for the snotty answer, BTW.

[Br1ck]

Carvin is no more, so won't be any help. You could use the XLR output to a powered speaker and you would not have any matching issues.

I have an AG 300. I don't think the speaker output on it has a separate volume control. It's tied to the master vol. The Carvin extension cab was identical to the amp minus the power.

[Ray(T)]

So 2 x 8 ohm in parallel equates to 4 ohm overall. Doesn't answer my question.

Thanks for the snotty answer, BTW.

Lower the impedance too much - damage the amp. Use too low a rated speaker - damage the speaker. Read the manual. (Another snotty answer!)

[Teak]

zz

[Teak]

Lower the impedance too much - damage the amp. Use too low a rated speaker - damage the speaker. Read the manual. (Another snotty answer!)

Read the manual many times. Not much info in it.

But you essentially answered my question.

Extension speaker has to be at least 8 ohms; thus, the lowest combined (parallel) impedance can be 4 ohms, no less. A 20-W extension will not allow as high a current flow as 50-W (what the AGE200 was rated at) so I won't be able turn up the volume as high without damaging the 20-W speaker.

Thanks.

[pops1]

Could buy the extension cab you want and change the speaker to a 200 watt speaker and put it in your extension cab. Problem solved, just get an 8 ohm speaker.

[EdHanrahan]

... if I buy a passive speaker that handles up to 20 watts ... I am assuming that the extension speaker becomes the weaker link if I don't get one that is rated up to 50 watts, or higher.

A BIG problem with comparing speaker specs is that "power handling", the ability to tolerate an electrical input without melting down, has no direct relationship with "sound efficiency", the ability to turn a power signal into some volume of actual sound.

It's entirely possible that, when fed a signal of, let's say, 3 watts (in most non-distorted uses, amplifiers loaf along at WELL below their rated power most the time), a speaker rated to handle 20 watts could be louder than another that's rated to handle 200 watts. But such "efficiency" is so rarely spec'd, and so incomprehensible, that most tend to ignore it. (OTOH, a higher-wattage-rated speaker might be no louder but far more accurate than a lower-rated one, and that's often considered a good thing).

So, assuming that distortion is normally avoided, a 20-watt "rated" extension speaker could work with a 200-watt amp, because the amp will rarely exceed the speaker's handling ability, and then only momentarily. I'm not recommending such, only saying that it can work based on the speaker's relative efficiency.

Aside comment on "power": It takes a doubling of electrical power (watts) to raise the acoustic signal by 3db, a doubling of acoustic power. BUT we humans don't hear that way - it normally takes an additional 10db of acoustic power for us to perceive "twice as loud". Thus, 40 watts, to us, is not twice as loud as 20 watts; that takes a 10-fold increase in amp power to about 200 watts. Or looking another way: 3db + 3bd + 3bd + 1db = 10bd, with each "3bd" requiring a doubling of available wattage.

While this really doesn't answer the original question, it should help explain why that question doesn't have a clear & precise answer.

[Dave Sheets]

Adding an extension cabinet will increase the volume you can get out of the system. But if you buy a cabinet that will only handle 20 watts, you are really limiting the power output of the whole system, which I think defeats the point of adding the additional cabinet. As Br1ck suggest above, using a powered PA speaker connected to the XLR output on the amp is probably the best way to go, than adds it's own amplifier and eliminates all the issues associated with impedance matching and power output levels, and you can pretty much get to whatever power levels you want. QSC and RCF make really nice, super clear high powered self-powered PA cabinets with price tags that reflect that. We have a couple of cheap Alto powered PA speakers that obviously don't have that kind of quality, but seem to do okay so far, and are much less. There are some Yamaha and JBL speakers that seem to do pretty well and are priced in-between those.

Acoustic music needs really high levels of clarity, and that means using relatively expensive amps and cabinets to get that clarity. Electric instruments can get away with "dirty" sounding speakers and cabinets, where there is some distortion. The Orange amps are meant for rock, where most guitar players want to hear distortion. Since you have an xlr out on the amp, running that line into a self-powered PA is the easiest way to get a lot of additional clean volume. Self-powered PA speakers can also be "daisy chained" together using XLR cables, so you can expand to multiple speakers if you really need to at some point.

Good luck with it.

[Mandobart]

I've been using an inexpensive Kustom KSC10M rated at 60 W as an extension cab with my AG300 ever since I bought my Carvin a few years ago.

[pops1]

While adding an extension cab to an amp will lower the impedance, it will also raise the power slightly too. The power however will now be divided between two speakers with each getting half of the power, providing they are similar. You won't really bet more volume, but you will get a wider dispersion. Given that most amps have an audio pot for a volume control from 6 to 10 doesn't really give you a tremendous volume change, but more intensity in the sound. An audio pot is way different than a linear pot and sounds way better, but is raising volume differently. Turn a Fender twin to 6, then to 10 it's louder, but not that much.

[Teak]

As Br1ck suggest above, using a powered PA speaker connected to the XLR output on the amp is probably the best way to go, than adds it's own amplifier and eliminates all the issues associated with impedance matching and power output levels, and you can pretty much get to whatever power levels you want.

We have a couple of cheap Alto powered PA speakers that obviously don't have that kind of quality, but seem to do okay so far, and are much less.

Acoustic music needs really high levels of clarity, and that means using relatively expensive amps and cabinets to get that clarity. Since you have an xlr out on the amp, running that line into a self-powered PA is the easiest way to get a lot of additional clean volume. Self-powered PA speakers can also be "daisy chained" together using XLR cables, so you can expand to multiple speakers if you really need to at some point.

Good luck with it.

Thanks for the brand names. I am going to check out the Alto line.

[Br1ck]

Never really a Behringer fan, but lately they have been making some powered speakers that sound surprisingly good. The 8 inch model is what my open mic uses for monitors, and when we used them in a pinch as mains, they filled a good sized room. As said before,you could daisy chain a pair if you wanted, and they were less than $200 each.

[Teak]

Never really a Behringer fan, but lately they have been making some powered speakers that sound surprisingly good. The 8 inch model is what my open mic uses for monitors, and when we used them in a pinch as mains, they filled a good sized room. As said before,you could daisy chain a pair if you wanted, and they were less than $200 each.

Like I said above, it helps to get brand recommendations. Looks like the Behringer B208D is the model to which you referred, and it is $179.99 new. Gives me something to compare with the Alto TX8 and LyxPro SPA-8. By moving past my initial choice of a passive speaker, the options increased greatly.

This is the type of advice I was seeking. Thanks!

[mandroid]

Daisy chaining 2 Galaxy audio 16 ohm 'monitor' speakers .. gets you 8 ohms.. https://www.galaxyaudio.com/products/hs4

since coverage and clarity seems at issue , you can put 2 of these on Mic Stands on either side of you,
facing the audience.

[jefflester]

One question is why do you need the extension speaker? 200W is pretty hefty for a dedicated instrument amp. Do you not have a PA that it is also feeding? Are you really playing that loud? Or perhaps the extension is to go somewhere else on stage for someone else to hear you? Or maybe you are already using it as a small PA.

[Verne Andru]

If you run a speaker with a lower output rating than the amp (be sure they are using RMS or some other standard so you compare apples to apples) without damaging the speaker but the end result will be that you are pushing the speaker into distortion, which may be the desired result.

I'm sure your Carvin amp has output indications such as 8 ohm speaker, etc. Changing impedance isn't necessarily a bad thing as the power and tonal changes may be what you want.

The make of speaker and type of cabinet should be chosen for the type of sound you are looking for. Electric guitar speakers/cabs are voiced for a pronounced mid-range and distorted sounds which might not be the sound you want from an acoustic instrument.

If you are going for a cleaner tone then get a speaker that has a higher rating than the amp so the speaker doesn't add breakup. Full range keyboard or PA speakers work well.

Speaker size and magnet type will also influence the tone as does open/closed back, ports, etc., so deciding on your sound first is key.

[Br1ck]

The likelihood of finding a speaker with the same sensitivity could be problematic. If the speaker is more or less sensitive than the Carvin's, it will be louder or softer. So if you can't find a used Carvin cab, I think a powered speaker is the way to go.

[Teak]

One question is why do you need the extension speaker? 200W is pretty hefty for a dedicated instrument amp. Do you not have a PA that it is also feeding? Are you really playing that loud? Or perhaps the extension is to go somewhere else on stage for someone else to hear you? Or maybe you are already using it as a small PA.

Good question.

Our trio (occasional quartet when drummer can make it) started off as just mandolin and piano. For past gigs inside an ice arena, I bought a Carvin AG200 pa that has six inputs and rated for 200W. We use a vocal mic, instrument pencil mic for mandolin (with the 48V phantom power), and keyboard directly in. The AG200 has two 6.5" speakers with a tweeter, but the piano sounds good enough through the Carvin that the piano player stopped lugging her amp around. In January we added a bass player who brings his own amp.

The goal is to get stereo sound from the Carvin. Thus I was looking at what Mandobart suggested above: add a passive speaker that was similar to what Carvin used to sell (AGE200, 50-W extension cabinet, 8 ohm). I want to place another speaker away from the Carvin amp to get a fuller sound. We are not interested in distortion; thus the suggestions for clarity are spot on.

There have been good options presented so far. I like mandroid's suggestion for using two monitor speakers put off to each side. The piano player owns a music store and has both a used active speaker and a used set of monitor (passive) speakers for me to try out before I buy.

Anyway, I am not a gear geek; thus, I was looking for advice. Now I have to decide what is best for our little trio which rarely needs amplification. Usually we do our gigs acoustically in smaller rooms.

Thanks.

[Br1ck]

Other than infrequent use, the fact you can be a four piece suggests to me time for powered PA speakers and a small mixer.

I own an AG 300. It's 12" speaker would handle a keyboard better IMHO. I can play bass through mine too.

But if it's working for you, no need to change.