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Has anyone had experience with Biema pro amps for (sub)woofer use?
http://www.biema.com/html/product/amplifiers/q.htm
Am looking for a moderate cost amplification to power the woofer section (2 x 12") in the NaO.
Someone at Madisound forums suggested the QSC RMX 850 as good value at USD$300, but here in Australia it costs USD$900.
:-(
Am considering the Q250 or Q400 (for Aussies, the Altronics product code is A4164 or A4170)
http://www.biema.com/html/product/amplifiers/q.htm
Am looking for a moderate cost amplification to power the woofer section (2 x 12") in the NaO.
Someone at Madisound forums suggested the QSC RMX 850 as good value at USD$300, but here in Australia it costs USD$900.
:-(
Am considering the Q250 or Q400 (for Aussies, the Altronics product code is A4164 or A4170)
I'm in fact looking into an Altronics amp which puts out 2x450w into 4 ohms, which is on special now for $450 and seems a bargain at that. The distortion seems low, however they didn't really specify it properly so it could be anything.
To me this looks like the best value sub amp in Australia. I was looking at the Behringer EP 2500 which has a bit more power and can be bridged, but it's only about 1.5 db more output for nearly double the cost. The response looks acceptable, which is another thing you have to watch with low cost PA amps.
I'm doing a search at the moment, but if you find anything out, or get some feedback, I'd be interested to hear your thoughts.
To me this looks like the best value sub amp in Australia. I was looking at the Behringer EP 2500 which has a bit more power and can be bridged, but it's only about 1.5 db more output for nearly double the cost. The response looks acceptable, which is another thing you have to watch with low cost PA amps.
I'm doing a search at the moment, but if you find anything out, or get some feedback, I'd be interested to hear your thoughts.
A late reply, but I managed to have a look under the hood for these Q400 power amplifiers.
Separate power supply ie. TWO toroid transformers power supplies with 3x 8,200uF caps and 10 output devices per side attached to a tunnel heatsink...In total this thing weighs a massive 20kg beasts, and there's no fancy casework to add to that weight.
Will try to take photos next time I check it out.
Definitely adequate for subwoofer use, if only I could figure out how good they would be for full range work.
Separate power supply ie. TWO toroid transformers power supplies with 3x 8,200uF caps and 10 output devices per side attached to a tunnel heatsink...In total this thing weighs a massive 20kg beasts, and there's no fancy casework to add to that weight.
Will try to take photos next time I check it out.
Definitely adequate for subwoofer use, if only I could figure out how good they would be for full range work.
I’m extremely interest in a cheap amp too but I need about 1000-1500wrms per channel for my subs, usually the weight tells you how much grunt the amp has some stereos state 3000watts and only weight 5-15kg and I know that’s a lie.
yes please take some photos
yes please take some photos
Hayden, what impedance are you looking for?
I bought the Behringer EP2500 which has 650w into 4 ohms and is stable down to 2 with 1200w into a 2 ohm load, or 2.4 kw bridged into 4 ohms. It costs around $600 and you I doubt you could beat it.
The cheaper Biema amps supply no schematics, so if they fail, they can't be repaired. This came from a pro retailer who also did repairs. I'd say the cheap Biemas are for intermittent subwoofer use, not for continuous high power use. I hear the fan is quiet, and this would suggest they built in less robustness - most pro amps run loud in the home with the fans when it isn't needed.
If you need that much power, then perhaps two EP2500s. A pair of EP1500 would actually do it, 1.4kw bridged mono into 4 ohms. You could probably pick up a pair for ~ $1000.
If for home use, then the fan is a pest and you would want it in another room, if you use it for movies.
I wouldn't read too much into the weight. There are a lot of design issues there. It doesn't tell you how much grunt it has. There are heavy amps with only a few hundred watts, and there are lighter amps with a lot more. You have to look at the design of the amp, what method of cooling they use, the casing, and so on. Of course, if it is cheap and light and claims ultra high power, you would be skeptical. If its a Crown, light and powerful, then it will be expensive. An amp can be made lighter by using light gauge sheet metal on the case, by using class D or other similar technology, and by minimising heatsink size by multiple fans.
I bought the Behringer EP2500 which has 650w into 4 ohms and is stable down to 2 with 1200w into a 2 ohm load, or 2.4 kw bridged into 4 ohms. It costs around $600 and you I doubt you could beat it.
The cheaper Biema amps supply no schematics, so if they fail, they can't be repaired. This came from a pro retailer who also did repairs. I'd say the cheap Biemas are for intermittent subwoofer use, not for continuous high power use. I hear the fan is quiet, and this would suggest they built in less robustness - most pro amps run loud in the home with the fans when it isn't needed.
If you need that much power, then perhaps two EP2500s. A pair of EP1500 would actually do it, 1.4kw bridged mono into 4 ohms. You could probably pick up a pair for ~ $1000.
If for home use, then the fan is a pest and you would want it in another room, if you use it for movies.
I wouldn't read too much into the weight. There are a lot of design issues there. It doesn't tell you how much grunt it has. There are heavy amps with only a few hundred watts, and there are lighter amps with a lot more. You have to look at the design of the amp, what method of cooling they use, the casing, and so on. Of course, if it is cheap and light and claims ultra high power, you would be skeptical. If its a Crown, light and powerful, then it will be expensive. An amp can be made lighter by using light gauge sheet metal on the case, by using class D or other similar technology, and by minimising heatsink size by multiple fans.
Hi Paul,
Got any internal pics of the EP2500?
As far as power specs go, it's a winner, with thanks to it's Class H topology manages 500/750/1200W into 8/4/2 ohms. It's also bridgeable for a monster 2.4kW into 4 ohms.
Ref: http://www.partsexpress.com/pdf/248-747s.pdf
The Biema Q400 is rated to 400W/600W into 8/4ohms, at 0.1% THD, 1Khz. Bridged it can do 1.2kW into 8 ohms. No ratings for 2ohms, so probably not recommended for 2ohms (not a big problem, but real downside it that it's not bridgeable for 4 ohm operation)
I would think the Biema is a class A/B topology, though I can't be certain (I'm no power amp expert). It would explain why it uses two very large transformers and dual mono power supplies.
Got any internal pics of the EP2500?
As far as power specs go, it's a winner, with thanks to it's Class H topology manages 500/750/1200W into 8/4/2 ohms. It's also bridgeable for a monster 2.4kW into 4 ohms.
Ref: http://www.partsexpress.com/pdf/248-747s.pdf
The Biema Q400 is rated to 400W/600W into 8/4ohms, at 0.1% THD, 1Khz. Bridged it can do 1.2kW into 8 ohms. No ratings for 2ohms, so probably not recommended for 2ohms (not a big problem, but real downside it that it's not bridgeable for 4 ohm operation)
I would think the Biema is a class A/B topology, though I can't be certain (I'm no power amp expert). It would explain why it uses two very large transformers and dual mono power supplies.
tktran,
I haven't dared to open it up! I'm not thrilled about getting near those PS caps! If you don't use speakon connectors on the rear, there is a screw on cover to avoid contact with any bare wire, since this thing has so much juice! I must say I'd be curious to see it now you mention that. I will at some point need to clean the air filters, but I find it stays cool most of the time, unless I feel the urge to turn up the volume on loud rock music.
I have seen a review online on someone's personal website, where he did open it up and run it through some tests, where he confirmed that the power ratings were accurate, and that the quality of its construction was sound.
The first PA supplier I spoke to regarding this amp said that it was more reliable than the entry level crown amps. He gave numbers of units failing as backup. Whether this is a reflection on the amp, or how users tend to use them is another thing. I'd expect those who choose crown are more likely to be those who will push their equipment harder and insist on reliability. The entry level crown amps were quite a bit more expensive, they have two fans of the same size and run noticeably louder. The only advantages to the crown I could see was that the passive attenuators seemed better quality (firmer), and the fact that it was a crown with a 3 year warranty instead of one.
For most diy subs out there, I'd say the Biema is a great choice as the fans are quiet and they are very cheap. I also think that sub plate amps are rarely well designed in terms of having the right response - no rumble filter option, boost where you don't want it, etc. This is a great alternative
I haven't dared to open it up! I'm not thrilled about getting near those PS caps! If you don't use speakon connectors on the rear, there is a screw on cover to avoid contact with any bare wire, since this thing has so much juice! I must say I'd be curious to see it now you mention that. I will at some point need to clean the air filters, but I find it stays cool most of the time, unless I feel the urge to turn up the volume on loud rock music.
I have seen a review online on someone's personal website, where he did open it up and run it through some tests, where he confirmed that the power ratings were accurate, and that the quality of its construction was sound.
The first PA supplier I spoke to regarding this amp said that it was more reliable than the entry level crown amps. He gave numbers of units failing as backup. Whether this is a reflection on the amp, or how users tend to use them is another thing. I'd expect those who choose crown are more likely to be those who will push their equipment harder and insist on reliability. The entry level crown amps were quite a bit more expensive, they have two fans of the same size and run noticeably louder. The only advantages to the crown I could see was that the passive attenuators seemed better quality (firmer), and the fact that it was a crown with a 3 year warranty instead of one.
For most diy subs out there, I'd say the Biema is a great choice as the fans are quiet and they are very cheap. I also think that sub plate amps are rarely well designed in terms of having the right response - no rumble filter option, boost where you don't want it, etc. This is a great alternative
How good is the EP2500 will it live up to a constant 1200wX2wrms without a lot of distortion and overheating? I don’t want it to damage my subs.
Into what impedance?
It is no different to any other amp. Pushed beyond its limits it will clip and you will get distortion.
Whether you will get the power you want depends on how you configure it. Bridged to drive a 4 ohm load you will get 2.4kw which is twice as much as you are looking for, however you would need two amps and this is probably overkill.
If you can find an amp that is better value for money for driving a high power sub, then I'd like to know what it is.
I have mostly answered your question in my previous posts, but I will add that I haven't pushed it to the extent that you might in a DJ situation where it might have to run all night. I'd expect that it would be up to the task, however I'm not experienced in this kind of context.
It does have thermal overload protection which should kick in before failure. You could test it out and if this becomes a problem with just one, you could use two. Then it would be running more comfortably with more headroom.
It is no different to any other amp. Pushed beyond its limits it will clip and you will get distortion.
Whether you will get the power you want depends on how you configure it. Bridged to drive a 4 ohm load you will get 2.4kw which is twice as much as you are looking for, however you would need two amps and this is probably overkill.
If you can find an amp that is better value for money for driving a high power sub, then I'd like to know what it is.
I have mostly answered your question in my previous posts, but I will add that I haven't pushed it to the extent that you might in a DJ situation where it might have to run all night. I'd expect that it would be up to the task, however I'm not experienced in this kind of context.
It does have thermal overload protection which should kick in before failure. You could test it out and if this becomes a problem with just one, you could use two. Then it would be running more comfortably with more headroom.
Well i noticed that some people were asking questions on what the biemaQ250 amplifier could handle,
im currently running 2 speakers off it in parallel and i don't need to even turn the amp up full to get enough out of the speakers, and im running 2x 18" 800RMs speakers, and they get plenty loud,
As for clipping the only time it happens to me, is when there is too much bass pumping through the channel, and that is easy fixed in a min by either turning the amp down a tad or turning the input down,
and i would post some photos of inside the amp, but i forgot to take pictures when i had it open, and the fans a really good, and they are only standard computer tower fans, i can run my system for a few hours and no distortion, no clipping, just great music blaring out non stop,
im currently running 2 speakers off it in parallel and i don't need to even turn the amp up full to get enough out of the speakers, and im running 2x 18" 800RMs speakers, and they get plenty loud,
As for clipping the only time it happens to me, is when there is too much bass pumping through the channel, and that is easy fixed in a min by either turning the amp down a tad or turning the input down,
and i would post some photos of inside the amp, but i forgot to take pictures when i had it open, and the fans a really good, and they are only standard computer tower fans, i can run my system for a few hours and no distortion, no clipping, just great music blaring out non stop,
Biema Q400 vs. EP2500
Hmmm
Behringer EP2500 vs Biema Q400
I have expiriece with both amplifaers like servicer and advanced user ,
Biema Q400 is the same amplifaer like Biema J46 but in other package (other front mask)
Biema Q400 is usual chinese amplifaer (product), if you read specifications it is hard, high power amplifaer, if you open it to see inside you will see a big transformer , hard power stage with a lot of high power transistors, big heatsinks and low,low quality fans, cheap PCB, and no so bad soldering and cablig. (chinese blue LEDs are usual for product like this)
Package (box), switch and connectors are not bad for cheap product like this.
Power and quality of sound
First time when you connect amplifaer, you think that you have very good product, but it's not true, this can't suply a lot of power (like specificaions say 600W per chanel in 4ohms) and the distorsion is large at 300W/4ohms !!! , mesured power at sine of 1Khz is 410W, if you compare with brand amplifaer it sound quiet and most bad tham "brand amp" specifid at 400W/4ohm.
EP2500
It's not bad solution, but stories like real 1.2KW/2ohm are not believable and not true.
I use this amp like start solutin , cheap, middle power amp, with good optimum price/performance, but not for bass section becouse it have low dump factor.
It's build from cheap materials, maximum optimized to produce it for lower costs , that is not same with bime Q400.
One think is very interesting that it's not so good like amp, but it's perfect like cheap product, the procent of burned EP2500 is minimal.
Storues like , use EP2500 in bridge on 4ohms load to get 2.4KW power are ilusion , becouse is not posible to get this power from too cheap amp.
For the end
I don't know the prices of both product on your market, but if the price are same, for bass section i will use biema, and for high/mid Ep2500
Both amps are not champions, and we can analyse it like cheap chinese solution .
Hmmm
Behringer EP2500 vs Biema Q400
I have expiriece with both amplifaers like servicer and advanced user ,
Biema Q400 is the same amplifaer like Biema J46 but in other package (other front mask)
Biema Q400 is usual chinese amplifaer (product), if you read specifications it is hard, high power amplifaer, if you open it to see inside you will see a big transformer , hard power stage with a lot of high power transistors, big heatsinks and low,low quality fans, cheap PCB, and no so bad soldering and cablig. (chinese blue LEDs are usual for product like this)
Package (box), switch and connectors are not bad for cheap product like this.
Power and quality of sound
First time when you connect amplifaer, you think that you have very good product, but it's not true, this can't suply a lot of power (like specificaions say 600W per chanel in 4ohms) and the distorsion is large at 300W/4ohms !!! , mesured power at sine of 1Khz is 410W, if you compare with brand amplifaer it sound quiet and most bad tham "brand amp" specifid at 400W/4ohm.
EP2500
It's not bad solution, but stories like real 1.2KW/2ohm are not believable and not true.
I use this amp like start solutin , cheap, middle power amp, with good optimum price/performance, but not for bass section becouse it have low dump factor.
It's build from cheap materials, maximum optimized to produce it for lower costs , that is not same with bime Q400.
One think is very interesting that it's not so good like amp, but it's perfect like cheap product, the procent of burned EP2500 is minimal.
Storues like , use EP2500 in bridge on 4ohms load to get 2.4KW power are ilusion , becouse is not posible to get this power from too cheap amp.
For the end
I don't know the prices of both product on your market, but if the price are same, for bass section i will use biema, and for high/mid Ep2500
Both amps are not champions, and we can analyse it like cheap chinese solution .
You certainly can use a P A Amp for your Bass Speakers .but unfortunately They can be a Little Noisy due to the Cooling Fans on them .I personally will try to get a Smcron Power Line 3 or Powerline 4 or maybe a Luxman M3 Or M5 or The Pioneer M3 or the Pioneer M4 or look for a Good Rotel 150 Watts per Channel Into 8 Ohms even a good old Yamaha should do the job for you. As audio Amps run on Class a ,&B and PA Amps are mainly in Class B and can be a bit Noisy due to the cooling Fans
It is just a suggestion .and hope that this will help your decision as my speakers are very effienct as I got a pair of Klipsch laScalas and they are around 1
06 DB efgient
It is just a suggestion .and hope that this will help your decision as my speakers are very effienct as I got a pair of Klipsch laScalas and they are around 1
06 DB efgient