is 200W from one amp the same as 200 W from another?

[aaguudis]

Am looking into buying an amp for the upright. Currently borrowing my school's which is a GK 400 RB (200w) going into an unknown cab. Sounds like crap, very electric/metallic/stringy sound(I have an underwood pickup, could this be part of the problem?) . But the thing is loud enough to play in the big band.

The amp I am currently looking at is the AI contra. This is supposed to be 200w as well (is that correct? 200w by itself but can get up to 300 with an ext cab?). But all the threads I have read on here suggest the contra doesnt do well in loud situations.

So are these 200W the same? I actually dont even need the contra for the big band, I can use the schools ( I dont play big band music outside of school, just small combo stuff), but it would be nice if I could use it instead of the GK.

Thanks

[LowNote]

I currently use an AI New Yorker, which recently replaced a first generation AI Contra, for much of my string bass playing. I play it with 18-piece big bands and plenty of small group stuff as well. As long as you aren't trying to fill a large hall, the Contra alone would be plenty of sound with a big band and it sounds wonderful in small group settings. If you are in a large hall, adding a single extension cabinet will also do the trick. The impedance matching of the Contra is also much better for an Underwood pickup plugged directly into the amp. Although this is not the best sounding pickup out there, it will work and will sound much better through the Contra than the GK. If you continue to use the GK, a small preamp would be a big help in making the Underwood sound better.

Erik Hansen
Los Angeles

[Chris Fitzgerald]

Originally Posted by ARGLEBARGLE

Am looking into buying an amp for the upright. Currently borrowing my school's which is a GK 400 RB (200w) going into an unknown cab. Sounds like crap, very electric/metallic/stringy sound(I have an underwood pickup, could this be part of the problem?) . But the thing is loud enough to play in the big band.

The GK 400 RB - which I used to own for slab gigs - sounds god-awful for DB. I can't say why, but it does, and for exactly the reasons you mentioned. IMO, of course.

The amp I am currently looking at is the AI contra. This is supposed to be 200w as well (is that correct? 200w by itself but can get up to 300 with an ext cab?). But all the threads I have read on here suggest the contra doesnt do well in loud situations.

So are these 200W the same?

There are a lot of variables when dealing with power ratings, and I honestly think it's best not to get caught up in the numbers game. The bottom line is, how do you like the sound?

That said, some of the variables:

Speaker efficiency: an efficient speaker can make a 100w amp seem "louder" than an inefficient speaker hooked up to a 400 w amp.

Coloration: Some amps get nastier the harder you push 'em. Some amps stay pretty clean up to their threshold. You have to play them to find out, and you have to determine if it is the amp or the speaker (or both) which is geting ugly when the volume creeps up.

Power ratings: I can't explain this as well as some of the techies up in the BG AMPS forum, but 200w is not twice as powerful as 100w in terms of how we percieve volume. Check up in BG for the actual figure, but I think you need something on the order of a 10 to 1 ratio to double the perception of volume.

Again, the best thing to do is to get your mitts on the amps you are considering and lets your ears decide. As expensive as some of these things are, it's worth the trouble. YMMV, of course.

[Bob Gollihur]

As Chris mentioned, speaker efficiency is something that has to be factored into the mix. If an amp is rated honestly, 200 watts = 200 watts... but you then get into the more esoteric area of headroom, which is really only a concern if you are playing at or near the full volume of the amp. This has to do with how gracefully the amp sounds when overdriven. But let's put that aside.

Speakers and their cabinets greatly affects the volume that you get from that 200 watts. Efficiency is the term, and it's usually measured in db. The cabinet Acoustic Image combos use is of the infinite baffle design- it has no ports (holes) but is sealed. This design tends to be less efficient than ported cabinets, and the AI is no exception. A ported design would be more efficient but it would call for a much larger cabinet.

For example, I received one of the new Euphonic Audio NM-410 cabinets, four tens and a horn. I used it to test an older generation Clarus head I received. That cab delivered an incredible amount of volume from that 120 watts, it hurt my ears... but it's a huge cabinet.

The Contra's speakers also don't "shout" like some larger ported cabinets, it was designed to make your bass sound bigger rather than give it a separate voice. In a highly competitive volume situation, some other speakers might be a better choice to cut through the mix.

That said, I love my Contra.

Disclaimer: I'm Acoustic Image's largest dealer.

[winston]

I've always liked the tone I get from my GK 400RB for double bass. I play a New Standard Cleveland laminated bass with Schertler Stat-B and K&K BassMax pickups and use EA Wizzy and Bergantino HT112 cabs. I usually roll off a little bit of treble and high mids and I'm good to go. Fellow musicians continually compliment me on the sound of this rig. To each his/her own, I guess. On the occasions when I don't want the coloration of the GK's preamp I run the pickup signal through a Fishman Platinum Bass EQ into the FX return of the GK.

Like others have said, an impedance-matching preamp will help your Underwood sound better through the GK. If money is no object, try a new amp. But if the unknown cabinet is contributing to the crappy sound a new head won't solve the problem.