Upgrading my 20 year old B&KAvR 507... need some help

[tpeter]

Using my older BK receiver from around 2002 its still a damn powerhouse. I also have the same Speakers from 2002, they are the Polk LSi15s , LSIC and LSiFX for the rears. My sub is a 2002 SVS CS Ultra with Samson1000 amp and also just added a PB3000 for duals..

So as the post states... would it be worth it to buy a newer AVR? I wouldn't want to spend more then 2k max. I would add HDMI and all the new DTX and Dolby sound formats that i cant play when using my XBOX Series X along with UHD BluRays... right now my BK switches to Dolby Pro Logic 2 which is annoying but honestly i own like 2 UHD movies, the other 99% is streaming content from Netflix etc all which use Dolby Digital 5.1.

My speakers are 4ohm and the BK powers them with no sweat playing at references levels for hours on end... That's what worries me about a 1500-2k receiver, they just seem cheaply built compared to my current. The dang thing weighs close to 60lbs !!

Thoughts?

Some other people said... Denon 3700 with an Emotiva A3 to power my front 3 would be good.. Im seeing some reviews saying the 3700 is handling 4ohm just fine.. Could i get away with just an AVR?

attached are some pics... I just moved in so havent dont cable management etc..

 

[peng]

Using my older BK receiver from around 2002 its still a damn powerhouse. I also have the same Speakers from 2002, they are the Polk LSi15s , LSIC and LSiFX for the rears. My sub is a 2002 SVS CS Ultra with Samson1000 amp and also just added a PB3000 for duals..

So as the post states... would it be worth it to buy a newer AVR? I wouldn't want to spend more then 2k max. I would add HDMI and all the new DTX and Dolby sound formats that i cant play when using my XBOX Series X along with UHD BluRays... right now my BK switches to Dolby Pro Logic 2 which is annoying but honestly i own like 2 UHD movies, the other 99% is streaming content from Netflix etc all which use Dolby Digital 5.1.

My speakers are 4ohm and the BK powers them with no sweat playing at references levels for hours on end... That's what worries me about a 1500-2k receiver, they just seem cheaply built compared to my current. The dang thing weighs close to 60lbs !!

Thoughts?

Some other people said... Denon 3700 with an Emotiva A3 to power my front 3 would be good.. Im seeing some reviews saying the 3700 is handling 4ohm just fine.. Could i get away with just an AVR?

attached are some pics... I just moved in so havent dont cable management etc..

Would have to know you mlp distance to the LSi15 and LSiC to figure out if you can get away without an ext. amp. Also, to be able to listen to reference volume for a minute or two just for the thrill is one thing, but to watch the whole Star War movie at ref level is something else, so what is your typical spl you need, would 5 or 10 dB below reference level be your norm?

Going from your B&K 150 W 8 ohms to the little 3700 105 W 8 ohms, you would likely lose about 2 dB of SPL at the most, all else being equal. The B&K may do much better into 4 ohms but it is still officially rated for 8 ohm speakers.

 

[tpeter]

Would have to know you mlp distance to the LSi15 and LSiC to figure out if you can get away without an ext. amp. Also, to be able to listen to reference volume for a minute or two just for the thrill is one thing, but to watch the whole Star War movie at ref level is something else, so what is your typical spl you need, would 5 or 10 dB below reference level be your norm?

Going from your B&K 150 W 8 ohms to the little 3700 105 W 8 ohms, you would likely lose about 2 dB of SPL at the most, all else being equal. The B&K may do much better into 4 ohms but it is still officially rated for 8 ohm speakers.

Im about 7 feet from the speakers... i prolly listen -5 on from reference but like to go reference once and a while for showing friends...

Rating is 7 X 185 w @ 4 ohm on the BK

 

[dougi]

Your centre seems to have a sensitivity of around 88dB SPL/1w/1m. Listening distance about 2m so ~82dB SPL/1W at the LP. To get to reference level (105) at the LP for that single speaker you would then need 200W. So you may be needing all of the power of the current AVR to get that. 5dB less then that is only 63W, which most AVRs should produce with multiple channels driven.

 

[peng]

Im about 7 feet from the speakers... i prolly listen -5 on from reference but like to go reference once and a while for showing friends...

Rating is 7 X 185 w @ 4 ohm on the BK

I downloaded the manual, there is no 4 ohm rated output, where did you get the 7*185W from? Even if is rated for 4 ohm, it cannot do 185 W with 7 channel driven, no AVR can, 2, or 5 channel driven, may be..

The manual shows:

Amplifier Specifications
Power rating @ 8 ohms 150 watts
Frequency response 5 Hz - 45 kHz
THD (S + N) 0.09 %
Damping factor 150
Current (peak to peak) 28 Amps per channel
Slew rate 14 V / μS
Dynamic headroom 1.4 dB

Anyway, if you need ref level at 7 feet, you would need about 225 W to get 105 dB with one speaker. Or 450 W from 10 feet. That's based on no room gain, and again, with one speaker only. I couldn't find any measurements for the LSi15, but I would assume it has some impedance dips and phase angles may not be benign, if they are anything like the LSi25. What saved your 507 is probably the 7 ft distance.

So I would say you need to grab an external amp for the LCR. You can get one for <$800 if you go with something like the NC502MP from Buckeye amp or VTV. At that price point, I don't know of any power amp that can match the NC502MP's output power and performance specs. The gain of those amps are a little low but 1.5 V will get you almost 225 W into 4 ohms. The 3700 can output 2 V at less than 0.02% THD+N and that would drive the power amp to output 400 W into 4 ohms.

 

[tpeter]

I downloaded the manual, there is no 4 ohm rated output, where did you get the 7*185W from? Even if is rated for 4 ohm, it cannot do 185 W with 7 channel driven, no AVR can, 2, or 5 channel driven, may be..

The manual shows:

Amplifier Specifications
Power rating @ 8 ohms 150 watts
Frequency response 5 Hz - 45 kHz
THD (S + N) 0.09 %
Damping factor 150
Current (peak to peak) 28 Amps per channel
Slew rate 14 V / μS
Dynamic headroom 1.4 dB

Anyway, if you need ref level at 7 feet, you would need about 225 W to get 105 dB with one speaker. Or 450 W from 10 feet. That's based on no room gain, and again, with one speaker only. I couldn't find any measurements for the LSi15, but I would assume it has some impedance dips and phase angles may not be benign, if they are anything like the LSi25. What saved your 507 is probably the 7 ft distance.

So I would say you need to grab an external amp for the LCR. You can get one for <$800 if you go with something like the NC502MP from Buckeye amp or VTV. At that price point, I don't know of any power amp that can match the NC502MP's output power and performance specs. The gain of those amps are a little low but 1.5 V will get you almost 225 W into 4 ohms. The 3700 can output 2 V at less than 0.02% THD+N and that would drive the power amp to output 400 W into 4 ohms.

Oh everything I google all show 185x7 at 4ohm

B&K AVR507

B&K AVR507

www.highperformancestereo.com

Every site I look up has those specs ... you know a lot more than me so I may be confused

 

[tpeter]

I downloaded the manual, there is no 4 ohm rated output, where did you get the 7*185W from? Even if is rated for 4 ohm, it cannot do 185 W with 7 channel driven, no AVR can, 2, or 5 channel driven, may be..

The manual shows:

Amplifier Specifications
Power rating @ 8 ohms 150 watts
Frequency response 5 Hz - 45 kHz
THD (S + N) 0.09 %
Damping factor 150
Current (peak to peak) 28 Amps per channel
Slew rate 14 V / μS
Dynamic headroom 1.4 dB

Anyway, if you need ref level at 7 feet, you would need about 225 W to get 105 dB with one speaker. Or 450 W from 10 feet. That's based on no room gain, and again, with one speaker only. I couldn't find any measurements for the LSi15, but I would assume it has some impedance dips and phase angles may not be benign, if they are anything like the LSi25. What saved your 507 is probably the 7 ft distance.

So I would say you need to grab an external amp for the LCR. You can get one for <$800 if you go with something like the NC502MP from Buckeye amp or VTV. At that price point, I don't know of any power amp that can match the NC502MP's output power and performance specs. The gain of those amps are a little low but 1.5 V will get you almost 225 W into 4 ohms. The 3700 can output 2 V at less than 0.02% THD+N and that would drive the power amp to output 400 W into 4 ohms.

And thanks for the reply on the amp part !

 

[peng]

Oh everything I google all show 185x7 at 4ohm

B&K AVR507

B&K AVR507

www.highperformancestereo.com

Every site I look up has those specs ... you know a lot more than me so I may be confused

Resellers can say whatever they want, and they definitely want to sell. I could not find any bench test results so I can only quote official specs by B&K.

To be clear, I am not saying it cannot do 185 W into 4 ohms, even the 3700 can do that, but would be at higher distortions/clipping and would be for a short duration.

In fact, I bet the 507 can output more than 200, 250 W or even a little higher than 300 W into 4 ohms, but a) not with 7 channel driven simultaneously, b) at higher distortions, may be 1%, c) for short duration only, and that may be fine depending on your listening habit.

There is a reason why a reputable company like B&K did not provide a blanket 185 W into 4 ohms spec, let alone with 7 channel driven. If they were to do it, they would most likely specify 185 W, or higher, under their specified conditions, again, such as how many channels driven simultaneously, at what distortion level, and whether it is for a short duration, or "continuous" basis.

Sorry about confusing you, just that it is complicated, unfortunately. This is Audiosciencereview.com after all.

Take a look of the manual and service manual/schematics yourself if you are interested:

To download you have to register with the site:

https://www.hifiengine.com/manual_library/bk-components/avr507.shtml

 

[peng]

Links to the seemingly best high quality lowest $/Watt power amps:

Buckeye 6 Channel Amplifier Review

This is a review and detailed measurements of the Buckeye Hypex NC252MP based, 6-channel amplifier. It costs US $1149 as of this writing. The owner/builder is @Buckeye Amps on our forum. The looks are fine for a well-priced build: The unit is quite light courtesy of rather thin sheet...

www.audiosciencereview.com

Buckeye Amps: New US based Hypex multichannel amplifier builder, line-up announcement!

Hypex NC502MP specs: - 450w @ 2ohm (per channel, peak) - 500w @ 4ohm (per channel, peak) - 350w @ 8ohm (per channel, peak) Hypex NC252MP specs: - 180w @ 2ohm (per channel, peak) - 250w @ 4ohm (per channel, peak) - 150w @ 8ohm (per channel, peak) PRICING: XL 8ch Aluminum Case (17"x13"x6")...

www.audiosciencereview.com

VTV AMPLIFIER Stereo Hypex NC502MP NCore Amplifier 500WX2 | VTV Amplifier

 

[tpeter]

Resellers can say whatever they want, and they definitely want to sell. I could not find any bench test results so I can only quote official specs by B&K.

To be clear, I am not saying it cannot do 185 W into 4 ohms, even the 3700 can do that, but would be at higher distortions/clipping and would be for a short duration.

In fact, I bet the 507 can output more than 200, 250 W or even a little higher than 300 W into 4 ohms, but a) not with 7 channel driven simultaneously, b) at higher distortions, may be 1%, c) for short duration only, and that may be fine depending on your listening habit.

There is a reason why a reputable company like B&K did not provide a blanket 185 W into 4 ohms spec, let alone with 7 channel driven. If they were to do it, they would most likely specify 185 W, or higher, under their specified conditions, again, such as how many channels driven simultaneously, at what distortion level, and whether it is for a short duration, or "continuous" basis.

Sorry about confusing you, just that it is complicated, unfortunately. This is Audiosciencereview.com after all.

Take a look of the manual and service manual/schematics yourself if you are interested:

To download you have to register with the site:

https://www.hifiengine.com/manual_library/bk-components/avr507.shtml

Attached are the specs comparing the BKavr vs their amps at that time.. I was always under the impression it was 185wx7 . I grew up in Buffalo NY and had a friend that worked for Bk in Buffalo where the company was from. At the time I worked at circuit city and employees could get the Polk Lsi series at 75% off. I wanted a good receiver to power the 4ohms so I reached out to my buddy Mike at BK and he recommended the AVR507 because of its rating.. I remember him telling me the receiver wouldn't break a sweat.. I took his advice and a actually ended up getting it for 1500 bucks with his discount And I think retail was close to 4K at the time... he wasn't lying this thing is still a beast 20 years later with never a hicup!! It's just now I'm missing out on the newer tech!

 

[tpeter]

Links to the seemingly best high quality lowest $/Watt power amps:

Buckeye 6 Channel Amplifier Review

This is a review and detailed measurements of the Buckeye Hypex NC252MP based, 6-channel amplifier. It costs US $1149 as of this writing. The owner/builder is @Buckeye Amps on our forum. The looks are fine for a well-priced build: The unit is quite light courtesy of rather thin sheet...

www.audiosciencereview.com

Buckeye Amps: New US based Hypex multichannel amplifier builder, line-up announcement!

Hypex NC502MP specs: - 450w @ 2ohm (per channel, peak) - 500w @ 4ohm (per channel, peak) - 350w @ 8ohm (per channel, peak) Hypex NC252MP specs: - 180w @ 2ohm (per channel, peak) - 250w @ 4ohm (per channel, peak) - 150w @ 8ohm (per channel, peak) PRICING: XL 8ch Aluminum Case (17"x13"x6")...

www.audiosciencereview.com

VTV AMPLIFIER Stereo Hypex NC502MP NCore Amplifier 500WX2 | VTV Amplifier

Thanks brother

 

[tpeter]

Could I just get away with a 3 channel amp for the LCR CHannels with the 3700

 

[peng]

Could I just get away with a 3 channel amp for the LCR CHannels with the 3700

I would say yes, it may be better for you to buy a 3 channel power amp instead of a 5 channel amp. Then you can add a second one, a less expensive one for the surround speakers if you feel there is a need for it.

Thank you for posting that comparison table that looks like is right from B&K. As I said before, I personally believe the 507 likely could do better than 300 W into 4 ohms, with 2 channel driven at probably up to 1% THD, if measured on the bench such as ASR's. Such 4 ohm ratings are typically not "continuous" rating even if the marketing material use that term.

The part I was questioning was the vagueness of the kind of specs like 185 WX7 because it may mislead people to think that is with all 7 channel driven at the same time. Not a big deal, just need to be aware if you are concerned..

Two things to keep in mind when seeing specs like that:

1) You cannot compare power output ratings between amps without specifying the THD, or THD+N levels. For some amps, the outputs @0.05% THD and 1% THD can be much more significant than others. Again not a big deal in general because doubling the output power only gets you 3 dB more in sound pressure level. People perceive about twice as loud when they crank the volume up by 6 to 10 dB.
2) For AVR, whenever you see XXX WX7, unless stated clearly, it would typically mean each of the 7 channel can output XXX W when only 1 or 2 channels are driven simultaneously.

 

[billyjoebob]

Back when I had my Marantz AVR7012 and 4 ohm Epos speakers, I used separate external amps, (a 1995 B&K amp for the fronts and a smaller Adcom amp for the rears) .
All the AVR had to power was the center. The Marantz was a great AVR with great features, but powering 4 ohm speakers to a reference level was NOT one of its strong suits.

 

[Jbrunwa]

The 507 was and still is a very good receiver. We had the Reference 50 pre amp and 200.5 amp, only replaced last year in our HT for similar reason. We bought a Denon AVR-X3700H. We have more efficient speakers, sit farther way in a large room, and listen at lower volume than you, but it had plenty of power. Since we kept the 200.5 we did our best at the time to test the HT using the Denon as a preamp vs driving the speakers directly, listening to each for extended time. In preamp mode we usually had the volume control about 3-5 dB lower, listening at -20 or -18 instead of -15 for example. We perceived just a smidge more harshness in the Denon amps at peaks, but it was really close, and it may have been our imagination. We have since made other major upgrades in both speakers and amps (Buckeye 6 channel NC502MP) but the differences between the amps are still reasonably subtle or imaginary. Another factor was the generous return policy when purchasing direct from Denon. We wish that B&K was still around though. Nostalgia, I suppose.

 

[tpeter]

The 507 was and still is a very good receiver. We had the Reference 50 pre amp and 200.5 amp, only replaced last year in our HT for similar reason. We bought a Denon AVR-X3700H. We have more efficient speakers, sit farther way in a large room, and listen at lower volume than you, but it had plenty of power. Since we kept the 200.5 we did our best at the time to test the HT using the Denon as a preamp vs driving the speakers directly, listening to each for extended time. In preamp mode we usually had the volume control about 3-5 dB lower, listening at -20 or -18 instead of -15 for example. We perceived just a smidge more harshness in the Denon amps at peaks, but it was really close, and it may have been our imagination. We have since made other major upgrades in both speakers and amps (Buckeye 6 channel NC502MP) but the differences between the amps are still reasonably subtle or imaginary. Another factor was the generous return policy when purchasing direct from Denon. We wish that B&K was still around though. Nostalgia, I suppose.

Good post man, BK is sort of back they have 2 high end amps available but expensive... Since you were in the same boat as me i question if spending 1500 on a Denon 3700 " more with Tax" then another 800 plus on a amp is worth it.. Will i really be able to hear the difference ? Hell it may be worse.. I will gain by being able to add more speakers but not at that point yet, and also HDMI ports etc... along with the newer sound formats.. Again is it worth spending 2500 plus to maybe get a little more ?

 

[Jbrunwa]

Good post man, BK is sort of back they have 2 high end amps available but expensive... Since you were in the same boat as me i question if spending 1500 on a Denon 3700 " more with Tax" then another 800 plus on a amp is worth it.. Will i really be able to hear the difference ? Hell it may be worse.. I will gain by being able to add more speakers but not at that point yet, and also HDMI ports etc... along with the newer sound formats.. Again is it worth spending 2500 plus to maybe get a little more ?

I personally wouldn’t buy external amps if I wanted the best value for my dollar, for me it was a diminishing returns luxury. There probably wouldn’t much reason to buy amps from the start, based on the analysis others provided. Besides HDMI and new sound formats, room correction like Audyssey has advanced. An in-home trial of an AVR with return privilege is IMO the best way to find out if a new AVR is worth it.

 

[Astrozombie]

Why not just shoot for the 135W~ Denon from the getgo? IF you're buying new how much more does it cost?

 

[tpeter]

I personally wouldn’t buy external amps if I wanted the best value for my dollar, for me it was a diminishing returns luxury. There probably wouldn’t much reason to buy amps from the start, based on the analysis others provided. Besides HDMI and new sound formats, room correction like Audyssey has advanced. An in-home trial of an AVR with return privilege is IMO the best way to find out if a new AVR is worth it.

Yeah ive thought about ordering one off amazon, their return policy makes its sweet to...

 

[tpeter]

Why not just shoot for the 135W~ Denon from the getgo? IF you're buying new how much more does it cost?

is that the 4700 thats 135 i think right?