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Disadvantages to a preamp/power amp

Some people have difficulty matching the output of some preamps with the input of some power amps. If you do your research before buying, it's not a problem. Occasionally you may find that the preamp which has the tone you want lacks the output specs you hoped for, for a given power amp connection. A combined pre/power head has by definition already been designed together for optimal operation.

Many of the new lightweight heads fit in the pocket of a gig bag and weigh under 10 lbs, while a pre/power rack is a minimum of 2RU and around 30 or 40 lbs including the rack, and may often be 3 or 4 RU and heavier than 40 lbs.
 
If you're moving up from combo amps,, it might be easier to make your next step a bass head and cab. Save that pre/pwr stuff for later, (if ever). I've been playing for a long time, and there's plenty of great bass heads on the market, one for every player.
 
It can be heavier, you have to buy a rack to house the components, you have to match the impedance of the preamp send to the power amp input...
That's all off the top of my head... i have advantages aout the wazoo, but disadvantages are a stumper for me
Read this, then read it again.


I'm headed down a similar road, so we can take this journey together

http://www.ovnilab.com/articles/preamp.shtml

Thanks for the link, it will be very helpful to reference and learn from. Out of curiosity, what made you decide to go down this road?




If you're moving up from combo amps,, it might be easier to make your next step a bass head and cab. Save that pre/pwr stuff for later, (if ever). I've been playing for a long time, and there's plenty of great bass heads on the market, one for every player.

I don't see how either choice could be easier or harder than the other, as long as you know what you're doing.
 
I'm going down this road because my bass rig is made up of two PA cabs and I want the flexibility to use them as pa cabs, so I'm trading my bass amp for a power amp and I bought a small mixer to run my effects into. There are several solutions I considered to stand in place of the mixer, but in the end I wanted the flexibility that the mixer offers. all my preamp ton comes from my hands and a small handfull of pedals, so I don't see the need for another preamp, but I am looking for that special deal (or and ashly dpx200)
 
ooh, and bass heads are easier because you never have to think about whether any pre/power setup will work together. also, not all preamps are rackmountable easily, which can b a pain. bass head is simplicity itself
 
The size and weight are a problem. I also bought a pre/power setup so I could use the power amp as a PA amp if needed. I thought it would be more flexible. But it is so awkward moving the rack system around compared to a head that I only ever used it at a jam space where it never moved.

And I never need to provide any of the PA anyway. Seems everybody and their dog in Ottawa has a PA ;)
 
For my uses power amps make a lot more sense since I'm also often supplying PA. Having swappability is nice then - and also when augmenting someone else's PA. Then too, I have a few preamps I like for not just bass but other applications. One of those is a Roland V-Bass, which is my main preamp and all my effects since 2003.

Another thing I like about power amps is that few heads are as robust when delivering actual rated wattages under difficult loads, often don't have very good shorting or thermal protection... Corners get cut when you are shaving weight and cost.
 
I would think there's a greater disadvantage to the combo head. I don't like being "stuck" with the power options some of these heads give you. I like the idea of a preamp that creates the sound I want, then matching that with enough power to make sure that sound gets out there. I also believe buying seperate components (depends on how you shop, of course) is also a bit cheaper..
 
I'm a former pre-amp/poweramp guy, and while the advantages are many, the main disadvantage is that you now have two pieces of gear. When problems arise, you'll first have to determine where the source of the problem is, and then send either the pre-amp and/or poweramp in for repair. I've been there twice before, and it's quite an inconvenience...

With a bass head, you just send one unit in for repair and let them figure out the source of the problem!
 
when you buy a bass head, isn't there still a preamp and a power amp section internally? It seems like you would have to figure out where the problem is coming from either way.

I need to buy my own amp set up, and I have been thinking about going with the separate pre and power amp. Are they any threads dedicated to this process? I did a search and was unsuccessful.
 
For me it's the weight issue. Even with a light power amp, like the new Carvins, the rack is still close to 30 lbs. Lotsa power though, more than I'll ever need. I recently bought a Shuttle 6.0, and Im going to see if I can get by with it in my current gig situation. If I can, checkout the classifieds !
 
I would think there's a greater disadvantage to the combo head. I don't like being "stuck" with the power options some of these heads give you. I like the idea of a preamp that creates the sound I want, then matching that with enough power to make sure that sound gets out there. I also believe buying seperate components (depends on how you shop, of course) is also a bit cheaper..

Makes a very very good point.