What watt bass amp for a 20 watt tube guitar amp?

[LazerBeakShiek]

How much bass amp wattage(tube or SS) goes with a 20 watt tube guitar amp?
Then-
Set up with a small 5 peice kit in the garage. How much vocal PA wattage is needed?

My ears like some bass.

 

[Old Music Guy]

How much bass amp wattage(tube or SS) goes with a 20 watt tube guitar amp?
Then-
Set up with a small 5 peice kit in the garage. How much vocal PA wattage is needed?

My ears like some bass.

That's an interesting question that is difficult to answer without a really lengthy explanation. To simplify, answer me this: What 20W amp are you using? 2. How loud do you intend to play? 3. Is the PA a separate unit? 4. Do you have the PA, or are you looking to buy one?

 

[rob aylestone]

Wattage can't be equated like this. I have 3 bass rigs - a small combo with 2 x 10" (I like 10" speakers) this has a 100W RMS amplifier in it. I have a 4 x 10" cab with a 350W amp and an 8 x 10" with a behringher 2000W (peak) amp. Oddly, the spec on this is a bit vague, but while it is loud, it's actually not much louder then the 350W. The 8 x 10" is an ashdown which is stupidly heavy, but sounds just like I want it.

The stupid thing is that a 30W AC30 can be excruciatingly loud, louder than my so called 2000W. In the olden days, a 30W tube guitar amp would often be sold with a corresponding 50W version for the bass player. Watts are not volume. I love the way the 2000W amp also says power consumption 110W. What the actual RMS rating of the 2000W peak amp is, I have no idea - Behringer don't seem to mention impedance either?

 

[DrewPeterson7]

Beyond Rob's excellent points, I think you're asking the wrong question anyway; it's not how loud you need to be to keep up wtih a 20w guitar amp, it's how loud both the guitar and bbass needto be to keep up with your drummer.

Clear answer is a couple of half stacks and neighbors be damned, btw.

 

[Old Music Guy]

To add to Rob's reply: My bass player plays through my 20W Fender Champion amp, while I use a 40W Blues Deluxe with my guitar. We get along great. What you really want to make sure of is a speaker that can handle frequencies well below 500Hz. Bass guitars put out very low frequencies that require a lot of power and a speaker that can handle that power.

 

[LazerBeakShiek]

. I love the way the 2000W amp also says power consumption 110W. What the actual RMS rating of the 2000W peak amp is, I have no idea - Behringer don't seem to mention impedance either?

Rob, yer going from Class A to AB to class D. Class D is going to say 20,000 watts for 100 watts comnsumption. Louder albeit less quality.

Im setting up something for drunk 50 y/o's to play rock n roll in the garage.

Rigs? right now, I play a ADA MP series or CAE 3+ for guitar. 20/20 50/50 or 100/100 tube power section. Marshall or Mesa.

That's an interesting question that is difficult to answer without a really lengthy explanation. To simplify, answer me this: What 20W amp are you using? 2. How loud do you intend to play? 3. Is the PA a separate unit? 4. Do you have the PA, or are you looking to buy one?

I have a mackie 1604 board and some power amps..100 tube PA or can go 1500/1500 watts mackie class AB pure SS.(I can play on almost lvl 2)
speakers are Yamaha 8 ohm 2x15" with horns and ports.
-senn e945's are used for garage voices.

keys go into 100/100 tube watts a side 8 ohms . Overkill.
speakers 1x15 and horn and port.

Bass .. Get this...Marshall VBA400 tube bass amp with 4x12 Cabinet ..split to an ADA MB-1 pre and ADA SS 500 watt power amp. 2 x10s/ 1x15 and a monster compression driver.

 

[LazerBeakShiek]

To add to Rob's reply: My bass player plays through my 20W Fender Champion amp, while I use a 40W Blues Deluxe with my guitar.

wow. So, 20 watts of bass is enough with 40 of guitar?

The Bass never seems to be heard over the drums and guitar(20/20) unless i use like 100/100 watts of tube power amp.

 

[LazerBeakShiek]

Rob is right then and there is no correlation between them. People end up just trying different combinations. 20,50,100 tube or 1000's of watt class D.

Is it suspicious that a 100 watt tube amp is as loud as 1000 watts of class D?

My Mesa 20/20 power amp is not as loud as 'X' scenario.

 

[rob aylestone]

The loudest guitar rig I ever heard was a queen tribute with 3 AC30 amps. Side of stage became an ear plug zone!
When my band went IEMs, I knew there would be kickback by the band leader as the change over approached. I was very happy with my bass DI’d into the PA. We switched to IEMs, they settled in, even with the boss. Then we did two shows with my amp on zero. He didnt notice. Then I didn’t rig it at all, left it on the van. He noticed straight away, but when I pointed out it had been a prop twice, he gave in. Nobody else even mentioned it. I do agree with the notion that volume just has to be enough to get over the drums.

 

[ecc83]

This is not a difficult question to answer...it is bloody impossible! Just too many unknowns (also "not givens")
As has been pointed out, bass needs a lot more power for similar volume than lead guitar. Take the venerable Celestion V30. Rated at 60W and a sensitivity of 100db/W/m but that is at the broad mid band. At just 100Hz it is some 10dB down (and keeps going down at ~6dB/oct) so you would need four times the power input at 100Hz to match the mid band level and bass players need more than an octave below that and 5 stringers go even deeper!

It has been said that a 50W bass amp with a decent BASS 12" speaker is barely a practice amp. The limiting factor for bands with a singer is how loud the vocals can go before feedback (assuming what they are singing is worth knowing about!) The rest of the band need to cut their SPL cloth accordingly. There is no reason why they cannot have a 600W bass amp and a "fridge sized" cab? You can always turn the fekker down! Many lead guitarists seem not to know this?

"power ratings" for amplifiers have long been away with the fairies and adpuff people. The only fair rating is continuous sine power into a stated resistive load at a specified distortion level. I have tested valve amps marketed as "100 watts" but they produced over 120W at just under 10%THD. And don't knock all class D amps. They have now reached a very high standard in terms of low distortion...Behringer PA might not be brilliant but there is MUCH better about now.

Dave.

 

[R D Smith]

Personal experience has shown, when it's too loud, the cops show up.

 

[Papanate]

1 million watts.

 

[ecc83]

1 million watts.

Ha! Ha! Serious example: my son plays bass with originally a 3 piece*, drums, lead G and vocals and he started off using a Peavery Bandit 112. On advice from his old man he was careful of the speaker and had no trouble with gigs in cafes and bars but then they are not a loud band (he would not stay if they were).

We did consider replacing the speaker in the Bandit with a proper 200W bass unit but then a 100W Harkte combo became available and that has proved more than adequate.

*Now added a flute but that has not upped the general SPL much of course!

Dave.