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Looking for Power Amp!

F

Frikkn

Oct 6, 2009
19
0
#1
Hi everyone!

I own a Line 6 Bass Pod XT Live with a built in crossover and am looking to buy a 2 channel power amp to bi-amp my 2x10 cabinet and 1x18 cabinet.

Now one of the first questions: What wattage region would you recommend? The 2x10 ashdown draws around 200W @ 8 ohm and the SWR 1x18 about 400 @ 8ohm.

I guess the logical thing would be to go for 300 watts per channel @ 8 ohm right?

Also, with a 2-channel power amp, what happens with the impedances? Is it like on my current amp? 2x8ohm in parallel=4 ohm? Or will the amp run at 2x8 ohms because of the 2 separate channels? Pardon my electronical ignorance, it both kind of makes sense in my head :P

Also is there anything I should look out for in power amps in particular? I've never bought JUST a power amp so maybe I'm overlooking key features?

How about this one? http://www.sessionmusic.co.uk/product/featured/Peavey-IPR-1600-Power-Amplifier.aspx
Puts out around 300W per channel @ 8 Ohm.

I know I will get people saying it's not worth it etc. I've been wanting to try this for a long time and I'm going to, if anything then for the experience!

Thank you very much in advance!
 
#2
Usually, with most two channel power amps, you can run bridged, or two channels. When running two channels, you can run different ohm loads, say 8 ohms out of one channel,and 4 ohms out of the other. Bridged usually means one load of 8 or 4 ohms. Some of the more reliable power amp brands are QSC, Crest, and Crown. There are many, newer, lightweight models available, especially from Crown.
 
#3
You are correct, driving each 8 ohm cab on it's own channel, each will remain an 8 ohm load.

The Peavy IPR amps get plenty of love around these parts, as do the Crown Drive Core series. Both offer excellent power for very little weight.
 
#4
Frikkn said:
Hi everyone!

I own a Line 6 Bass Pod XT Live with a built in crossover and am looking to buy a 2 channel power amp to bi-amp my 2x10 cabinet and 1x18 cabinet.

Now one of the first questions: What wattage region would you recommend? The 2x10 ashdown draws around 200W @ 8 ohm and the SWR 1x18 about 400 @ 8ohm.

I guess the logical thing would be to go for 300 watts per channel @ 8 ohm right?

Also, with a 2-channel power amp, what happens with the impedances? Is it like on my current amp? 2x8ohm in parallel=4 ohm? Or will the amp run at 2x8 ohms because of the 2 separate channels? Pardon my electronical ignorance, it both kind of makes sense in my head :P

Also is there anything I should look out for in power amps in particular? I've never bought JUST a power amp so maybe I'm overlooking key features?

How about this one? Peavey IPR 1600 Power Amplifier :: Session Music The UK's No1 Karaoke Specialists - Karaoke Machines Players CDG Discs And Equipment
Puts out around 300W per channel @ 8 Ohm.

I know I will get people saying it's not worth it etc. I've been wanting to try this for a long time and I'm going to, if anything then for the experience!

Thank you very much in advance!
Click to expand...

Yes....8 ohms / side. I would aim for something that does 400-500 watts per side / 8 ohms and bridgeable. More than what you need at the moment but will save you from scrambling should you choose to upsize / upgrade enclosures.

Riis
 
#5
Thanks for the quick and helpful responses, that's cleared up a few things right away! Would 400W per side be overkill for the 2x10? I guess in the end it will only clip/damage the driver if I turn the 2x10 channel up too far right?
 
#6
Gutshots of Carvin HD1500 power amp. Impressed so far. UPS guy could not believe he was handing me a rackmount amp. Pretty much what you will find in the power section of their BX1500 head as well...

HD1500.jpg

HD1500a.jpg


BOTH CH RMS continuous
- 8 ohms: 300/300 watts
- 4 ohms: 450/450 watts
- 2 ohms: 750/750 watts
BRIDGED RMS continuous
- 8 ohms bridged: 900 watts
- 4 ohms bridged: 1500 watts
 
#7
^ This. I had a feeling that when I got my BX1500, that the power section was the HD. Thanks for taking the time, Greenboy.
 
#11
Frikkn said:
Hi everyone!

I own a Line 6 Bass Pod XT Live with a built in crossover and am looking to buy a 2 channel power amp to bi-amp my 2x10 cabinet and 1x18 cabinet.

I guess the logical thing would be to go for 300 watts per channel @ 8 ohm right?

....

I know I will get people saying it's not worth it etc. I've been wanting to try this for a long time and I'm going to, if anything then for the experience!

Thank you very much in advance!
Click to expand...

First of all, don't let people tell you what to try and what not to try. There's as many people here as in the real world that are closed-minded and think that you have to be like them. Ignore them.

I think your amp choice of 2 x 300W is sound, but in the interest of upgradeability you may want to think about shooting a little higher, like 400 x 400 to handle headroom aspects.

One thing I'm missing with my latest amps (low wattage tube) is the extra headroom for low notes. I was totally digging that in my Mesa MPulse 600 - I didn't need all that power, but having it on reserve is super cool.

Don't know how long you've had the POD - I still have one that I use for practice and in a pinch I wouldn't hesitate to use it with a power amp for a rehearsal, but a few words of advice:

-Don't tweak the tone patches with a pair of headphones - it will not sound the same thru your rig.

-You need to volume normalize the patches - dunno if this is still a problem, but for some unknown reason Line 6 thinks it's OK for two patches next to each other to be different in volume by 15db. If you have a quiet one cranked and you switch to the loud one not only will you piss off your bandmates, but you can blow your speakers.

I bought mine probably 6 years ago and gave it a shot what you're suggesting. It wasn't for me, but it wasn't the tone that was the issue. I thought that they did a really fantastic job with some of the amp models and I found some great patches on the forum.

What I had trouble with was what I have trouble with in a chinese restaurant - there's too much stuff on the menu! It wasn't easy enough for me to tweak things because of the interface, which while not bad, it's more convoluted than having amps and effects in real life where you have access to all the knobs.

Good Luck, I think when you get it set up you'll be pretty happy with it. But HEED MY WORDS - volume normalize and maybe even delete those few stupid loud patches before you blow something.

CM
 
#12
Frikkn said:
... Would 400W per side be overkill for the 2x10? I guess in the end it will only clip/damage the driver if I turn the 2x10 channel up too far right?
Click to expand...

With independent R/L level controls the fact that the amp is rated higher than the speaker cabinet is not a problem. You don't have to turn the channel feeding the 2x10 up all the way. Use your ears and find a good balance.

Also note that even if the channels are turned up fully, you are not sending 400w to either cabinet with no signal going through the amp. Even with signal, you will seldom use the full rated power of an amp. That figure is provided to specify the amount of relatively undistorted power the amplifier is capable of generating.

That said, the advice to go with the higher rated amp is pretty solid, as it buys you much more flexibility for future cabinet options, with relatively little additional cost and practically no additional weight.


Colonel Monk said:
Uh, wow.
...
Is that because of the new class D thing where they don't need transformers?

I do hope the price of such amps comes down eventually, they sure do you less materials, sheesh...

CM
Click to expand...

Not specifically the class D part, but the SMPS (switch mode power supply) part. But it all adds up to lower weight, lower heat, relatively high efficiency / output for a given package.

As for the cost, I for one am pretty stoked about the low cost - high output of these things. Besides, we're probably saving quite a bit in shipping fees alone!
 
#13
JdoubleH said:
With independent R/L level controls the fact that the amp is rated higher than the speaker cabinet is not a problem. You don't have to turn the channel feeding the 2x10 up all the way. Use your ears and find a good balance.

Also note that even if the channels are turned up fully, you are not sending 400w to either cabinet with no signal going through the amp. Even with signal, you will seldom use the full rated power of an amp. That figure is provided to specify the amount of relatively undistorted power the amplifier is capable of generating.

That said, the advice to go with the higher rated amp is pretty solid, as it buys you much more flexibility for future cabinet options, with relatively little additional cost and practically no additional weight.




Not specifically the class D part, but the SMPS (switch mode power supply) part. But it all adds up to lower weight, lower heat, relatively high efficiency / output for a given package.

As for the cost, I for one am pretty stoked about the low cost - high output of these things. Besides, we're probably saving quite a bit in shipping fees alone!
Click to expand...

+1. You can get about 1500 watts, in a 10 lb Crown Drivcore for less than $400. Back in the day, that would have bought you about 150 watts at 30 lbs.
 
#14
Colonel Monk: I'm surprised how no one has said anything negative towards my idea yet. On the Warwick forum the only answers I seemed to receive were along the lines of "waste of money, no real difference, not worth trying". That was rather defeating, being ridiculed a bit for wanting to experiment. In the end it's my money and I love spending money on music gear, if it doesn't work out its always ebayable! Worst case scenario I sell it again and I walk away with a bit more experience in something new...

Enough rambling! I've owned the POD for several months now. I regularly use it with headphones, especially due to the auxiliary input which is just fantastic! I already have 2 sets of patches for all my basses, one for headphones and one for normal use.
What you mentioned about volume normalizing.... um yes I found that out the hard way haha made me jump a bit when it happened but I sorted it all out :D

I know what you mean about it having a bit too much to choose from, I found it rather confusing at first especially since I only owned single effect pedals before this. I will probably never use it all but I like having the options there plus it's brought me one step closer to finding my sound I think.


JdoubleH: Thank you, that was all I needed to know! Straight to the point, I like it. I wish I came to this forum in the first place.

When it's all setup I might do a little review and "document" my findings, some might find it interesting!

Also everyone else thanks for the great input, I really didn't think people would care much. The Warwick forum has been a bit of a letdown in that respect... Instead of giving information they were questioning my every action...don't know why they feel the need for me having to justify my purchases to them :confused:

Peace :bassist:
 
#15
Yeah I can't stand naysayers jumping in without even reading your post and then telling your your idea is dumb.

I can't promise you you'll love the results, YMMV, I thought it was doable. When I had fewer amp rigs (I'm on my way to having 6 different rigs) I was travelling an hour each way to rehearsal and just wanted to use the POD thru the PA. It worked fine-ish, but was a crap Johnson PA. To be honest, I was suprised how well it did work. Then I tried the poweramp/cab thing which was much better, but ultimately for reasons stated moved on.

It's still a cool solution. When I head back to the midwest on the holidays to visit family and friends I bring the POD with me. I have a Squier P BASS back there and will just connect the POD to a friends PA or powered speaker to get my Jam On. Many naysayers don't have these kind of needs.

The controls are a bit daunting and probably is the reason so many people decide to hate on it. Once you get your patches dialed in you can get over that.

Good Luck
 
#16
I use one of the new IPR series Peaveys, and have since sometime last spring. I've had no troubles with it performing as planned. The amp weighs in at about 7lbs. Here's a shot of the inside:

Invalid Link Removed

This is an IPR-3000. While I was interested in the 1600, I was carefully weighing a number of factors. First off, I can run each channel of the 3000 at 8ohms, for just under 500w per cab. I can also run both cabs off of one channel for ~500w per cab. Giving me the same power output for my setup but freeing up an extra channel as needed on stage. I also have a bridging cable, which gives me 'full' wattage out of the amp into a 4ohm load. Can my cabs use ALL of the voltage swing available when bridged? No. But both cabs CAN use more than 500w comfortably, and I'm a fairly careful and competent at monitoring my stage rig.
 
#17
Colonel Monk said:
Uh, wow.

Is that because of the new class D thing where they don't need transformers?
Click to expand...

Class D amps have never needed output transformers as is true of most SS amps. They do however, have to have a transformer in the power supply to isolate from the mains. Transformers for 50Hz operation have to be larger than those used on 60Hz. In switch mode supplies the mains is converted to a higher frequency. Carvin operate theirs at 100KHz, and at that frequency the transformer can be really small.

Simply put but I hope you understand. :)
 

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