Adding a power amp to AVR

[ljg2016]

Hello, I'm new!

I have watched a lot of the audiophile videos and read a very long thread from 2005 to 2011 on the Behringer A500. The outcome of all of this is that I would like to try adding a power amp to my AVR to improve sound quality, particularly when listening to music in stereo mode.

I have ordered a Behringer A500 from Amazon, as they just have got some in stock at a very reasonable price (£124), with 3 years warranty, and they have a good returns policy if it doesn't work out.

But I am also considering other power amps, such as the Crown XLS 1002 /1502 that I can get for about £300 to £350.

My existing set up is Kef iq10 / iq60C / iq50 for 5 speakers and a MS-309 sub.
I have three AVR's in the house (different rooms) and find that the Sony 3500ES sounds best in the main room, so I'm using that, it has a full set of pre-outs.

The room is fairly medium sized for the UK, which is probably small for the US, and the main seating position is about 4 meters from the front speakers. I do like to crank up the volume sometimes for music and action films, but nothing too crazy.

I am happy with a 5.1 set up, and I'm not interested in adding more speakers. The lack of new technology support in the amp is a bit annoying, but I can use dual HDMI out from sources as a workaround, so I think all I am missing is DTS:X but I have no content that has that as a soundtrack, at present.

So, my questions are, will the Behringer A500 be enough for this set-up, and would I just be wasting cash if I go for the Crown instead? Also, will there be any risk to the speakers by having them run by such a powerful amp. And lastly, would I be better off just buying a more expensive AVR?

Thanks for reading!

lisa

 

[Swerd]

To summarize:

Your KEF speakers IQ50 and IQ10 speakers seem to have modest power requirements. KEF recommends 15-130 watts for the IQ50 and 10-100 watts for the IQ10. I didn't look up the IQ60 center channel speaker but it's safe to assume it is similar. You are using a separate subwoofer which I assume has a built-in amplifier.

Your Sony 3500ES AVR can deliver 100 watts/channel (at 8 ohm load, 20-20kHz, at 0.09% THD). It is important to note that this measurement was done while driving two channels and not more. When driving 5 channels it will deliver less power, but it is unknown how much less.

The Behringer A500 can deliver 125 watts/channel while driving two channels with 8 ohm speakers. In the USA it sells for $200.

The Crown XLS1002 can deliver 215 watts/channel while driving two channels with 8 ohm speakers, and sells in the US for $300. Under similar conditions, the Crown XLS1502 provides 300 watts/channel and sells for $390.

Your choices are to use the Sony alone at no cost, the Behringer A500 at $200, the Crown XLS1002 for $300, or the Crown XLS1502 for $390.

I would recommend you try the Sony AVR alone long enough for you to assure yourself that is or isn't adequate for you. It may be good enough.

If you must buy an external 2-channel amplifier, I'd reccomend the Behringer A500. While its 125 watts/channel may not make an audible difference over the power available from your Sony, it will add an external power supply, and relieve the Sony from driving the KEF IQ50s.

I don't see any added benefit from spending the extra for either of the two Crown amps.

 

[TLS Guy]

Hello, I'm new!

I have watched a lot of the audiophile videos and read a very long thread from 2005 to 2011 on the Behringer A500. The outcome of all of this is that I would like to try adding a power amp to my AVR to improve sound quality, particularly when listening to music in stereo mode.

I have ordered a Behringer A500 from Amazon, as they just have got some in stock at a very reasonable price (£124), with 3 years warranty, and they have a good returns policy if it doesn't work out.

But I am also considering other power amps, such as the Crown XLS 1002 /1502 that I can get for about £300 to £350.

My existing set up is Kef iq10 / iq60C / iq50 for 5 speakers and a MS-309 sub.
I have three AVR's in the house (different rooms) and find that the Sony 3500ES sounds best in the main room, so I'm using that, it has a full set of pre-outs.

The room is fairly medium sized for the UK, which is probably small for the US, and the main seating position is about 4 meters from the front speakers. I do like to crank up the volume sometimes for music and action films, but nothing too crazy.

I am happy with a 5.1 set up, and I'm not interested in adding more speakers. The lack of new technology support in the amp is a bit annoying, but I can use dual HDMI out from sources as a workaround, so I think all I am missing is DTS:X but I have no content that has that as a soundtrack, at present.

So, my questions are, will the Behringer A500 be enough for this set-up, and would I just be wasting cash if I go for the Crown instead? Also, will there be any risk to the speakers by having them run by such a powerful amp. And lastly, would I be better off just buying a more expensive AVR?

Thanks for reading!

lisa

To be honest with you, I do not think that you will notice any difference with the addition of a power amp to those speakers.

Your receiver seems to be able to provide the power those speakers need.

Those speakers are relatively small. If you really did crank it with one of those amps I think you could well damage them. Those amps certainly have enough power to fry those speakers and your Sony Receiver likely could also.

If you really think you do need higher spl. then you need larger and more sensitive speakers.

I doubt the speakers will play louder with the larger amp. Those small voice coils will heat as you increase power, the resistance will go up and power output will not go up commensurately. This is called dynamic thermal compression. Next step in the process is fried voice coils.

The other thing to remember is that you have to double the power to get a minimal 3db increase in spl. Those speakers will not take 200 watts. To double your spl you need 1000 watts per channel and speakers to handle that.

The other issue is what music you listen to. Pop music has more continuous power and the speakers don't get a break which makes them more prone to burn out on this program.

Classical music on the other hand has much greater dynamic range and the voice coils get a break to cool off. Classical music does however in my view require greater power reserve from speakers and amps.

 

[ljg2016]

Thank you both for your responses and for taking the time to look at the sepcifications of my equipment. Much appreciated

I think my research had led me to a similar conclusion, but it's really nice to have it confirmed by someone who almost certainly would no more about all of this stuff than me!

I am not looking for more volume, but more quality, particularly in music in stereo mode. I find that when a music track gets a bit busy and loud, such as a favourite Gomez track I have, all the sounds seem to clash together and makes me feel anxious, whereas before I moved house (smaller room in the old house) it sounded much more mellow and I could pick out the individual voices and instruments, I am trying to get that nice relaxing clear sound back. I know in theory the Sony amp should be enough, but in reality, it is just not sounding as good as it has before.

It could be that these speakers are not good enough for the larger room in the new house, which will be a real pain, as they obviously match the centre and surrounds, and changing them sounds expensive!

I guess, I will give the Behringer an audition, be very careful on levels, so as not to cause any speaker damage, and if it sounds no better than just the Sony AVR on it's own then I'll send it back and maybe think about a speaker upgrade instead.

Thanks again for your contributions.

 

[lovinthehd]

I also doubt the amp will improve anything but sometimes you have to find out for yourself. Sounds like you may simply be asking more of them in that new larger room, or don't have them well positioned or the room has other acoustic issues (room and speakers are the larger influence on sound quality, not the electronics). Maybe post up details/pics of your setup for ideas.

 

[ljg2016]

Okay, thank you. I attach some photos of the room, the measurements from longest wall to longest wall is approx 18 feet x 13 feet, if you have any suggestions on placement or acoustics improvements that would be great! The sub woofer is behind the sofa between the surrounds, so out of shot.

 

[TLS Guy]

View attachment 18909 View attachment 18910 View attachment 18911 View attachment 18912

Okay, thank you. I attach some photos of the room, the measurements from longest wall to longest wall is approx 18 feet x 13 feet, if you have any suggestions on placement or acoustics improvements that would be great! The sub woofer is behind the sofa between the surrounds, so out of shot.

Those photographs are helpful and tell me what you problem is. You do not have nearly enough soft furnishings, especially the floor.

You have the speakers right on hardwood floors. You will have a very nasty first reflection. That will muddy the sound right away and obscure detail. The speakers need to be on a soft rug extending at least 6 ft beyond the front of the speakers. Some soft wall furnishings would also help a lot. More soft chairs would also help.

Also you need to experiment with sub location as the room from the pictures looks to be relatively square, with no long very dominant dimension.

To me that looks like a difficult room. It definitely needs some deadening, especially the floor.

 

[ljg2016]

Okay, thanks, that's really helpful. It's a new build house, we have not been here long, and I am yet to decorate that room, so adding more rugs and soft fabrics is definitely do-able.

I don't have an issue with bass sounds actually, I like that when watching films the explosions make the sofa vibrate!

I have heard of sound absorption materials, I think it might be possible to add some soft/foamy panels to the long bare wall, in place of art, not my first choice, but I'll look into it. I'll experiment first by draping some rugs / blankets around and see what effect that has on the sound.

Thanks for all the help so far.

I know you can't be absolutely sure, but in your opinion do you think those floorstanders should be adequate to fill that room with sound, if I can get the acoustics right?

 

[AcuDefTechGuy]

I wouldn't mess with using any external amps for your system because I don't think it will make any difference.

 

[TLS Guy]

Okay, thanks, that's really helpful. It's a new build house, we have not been here long, and I am yet to decorate that room, so adding more rugs and soft fabrics is definitely do-able.

I don't have an issue with bass sounds actually, I like that when watching films the explosions make the sofa vibrate!

I have heard of sound absorption materials, I think it might be possible to add some soft/foamy panels to the long bare wall, in place of art, not my first choice, but I'll look into it. I'll experiment first by draping some rugs / blankets around and see what effect that has on the sound.

Thanks for all the help so far.

I know you can't be absolutely sure, but in your opinion do you think those floorstanders should be adequate to fill that room with sound, if I can get the acoustics right?

I think those speakers should fill the room at sane volume levels. Getting good quality and high spl is an exponential expense curve, as you tend to get one without the other unless you go all out.

One caveat though. Those speakers use coaxial drivers. As Dennis Murphy sated here in a recent post, those drivers are difficult to use. He has not had success.

I think the major problem is dispersion. The woofer cones acts as a wave guide limiting dispersion. Now I know this may seems counter intuitive, but the more live the room, the better dispersion you need in my view, as long as the off axis sound mirrors the on axis sound. So the choice of speaker may be problematic in that room. You will have to see how deadening it a little helps. Do not over deaden the room, reflected sound is essential to realistic reproduction. Some ambient rooms can sound very good indeed, but often they don't.

I do use coaxial drivers in my center speaker and did a lot of design work on it. It uses a SEAS driver made under license from KEF for the use of some of their research. In a center speaker limited controlled dispersion is an advantage, as you can scheme it to cover the listening windows, and minimize interference with the left and right speakers. So I have had great success using a coaxial drivers for center speakers. I have to say I would be reluctant to use coaxial drivers as mains, but can't say I would rule it out.

 

[mtrycrafts]

...

I am not looking for more volume, but more quality, particularly in music in stereo mode. ...

This is good info. As others mentioned, more power or a different amp will not change what you hear in that room.
Speakers and room acoustics is where it's at.

 

[Swerd]

Yes, your photos are helpful. They certainly confirm what we all, including yourself, believe about more amplifier power – that is unlikely to address the sound problem you described:

I am not looking for more volume, but more quality, particularly in music in stereo mode. I find that when a music track gets a bit busy and loud, such as a favourite Gomez track I have, all the sounds seem to clash together and makes me feel anxious, whereas before I moved house (smaller room in the old house) it sounded much more mellow and I could pick out the individual voices and instruments, I am trying to get that nice relaxing clear sound back. I know in theory the Sony amp should be enough, but in reality, it is just not sounding as good as it has before.

In addition to TLSGuy's suggestions, I have a simple experiment for you to try, at least temporarily. Move the KEF IQ50 towers a bit further away (6-12 inches or more) from the wall behind them. Also move your area rug a bit closer to the speakers. Both of those simple actions will reduce the reflected sounds from the wall and floor relative to the sound coming directly from the speakers. Listen to some music, such as that Gomez piece, and see if that improves the sound.

I understand that it may be impractical to leave the speakers in that location, but it would be helpful for you to know that some simple, and hopefully low cost, alterations can improve what you hear.

 

[ljg2016]

Well, thanks again for everyone's help, I have spent a fun evening moving everything around, and have definitely heard some improvement to the sound. The 'sweetspot' seems to be as shown in the photo. Not the most practical location, but will have to find a way to make it work, a bigger rug might be a good start!

I'm still curious to see what (if any) difference the Behringer will make, so I'll update when it arrives and I've had time to experiment.

Thank you!

lisa

 

[mtrycrafts]

Well, thanks again for everyone's help, I have spent a fun evening moving everything around, and have definitely heard some improvement to the sound. The 'sweetspot' seems to be as shown in the photo. Not the most practical location, but will have to find a way to make it work, a bigger rug might be a good start!

I'm still curious to see what (if any) difference the Behringer will make, so I'll update when it arrives and I've had time to experiment.

Thank you!

lisa

Just be careful comparing the two amps in a sighted manner, and no level matching, as the subconscious bias will be influencing the brain, a lot. And no, you cannot will it one way or the other.
At least it will be a relatively inexpensive experiment.
Have fun experimenting.
ps
you may also want to experiment with slightly turning the speakers towards the listening position, called toe in.

 

[ljg2016]

UPDATE!

Just thought I would re-visit and let you know that all your help was not in vain, and I finally have things sorted out and sounding wonderful

The biggest improvement was the rug, and the speaker placement. That really got rid of the harsh sounding treble, and made everything sound much warmer and mellow.

I also decided to get a new CD player, a Marantz CD5005, as I wondered if my 15 year old Denon player might not be performing at its best. This was a small improvement in sound quality, it has three sound modes, including a pure direct mode which I can hear a difference between.

The Behringer A500 power amp is also staying. It is not a massive improvement, but it certainly does sound better with music in stereo mode that just using the Sony AVR. The Sony sounds a little 'muddy' the Behringer sounds crisper, and I can hear the different instruments and voices clearer. It has introduced a small buzz and the odd popping sound, so I am going to look into getting a mains conditioner device for the room.

I also got a new blu ray player whilst I was on a spending spree, purely because the Xbox One is horrible as a blu ray / dvd player, and I wanted one with dual HDMI outs so I can put video straight to the TV for 3D discs, and audio direct to the AVR to get the HD audio formats.

I also replaced the kef speaker jumpers with some I made myself out of some left over speaker cable, this probably made no difference at all!

So thanks again to everyone that helped me out with this, great forum, and I really appreciate it!

Here is a pic of the new set-up, complete with the 70's rug..