B&K 507 vs Emotiva MMC-1/XPA-5

[kordon]

Thoughts or suggestions? I've got the separates bug.

 

[kordon]

Nobody has an opinion?

 

[cfrizz]

Go for the separates. I started out with 2 channel separates years ago, then got a receiver to get into HT, now I'm back to separates and I will never go back to a receiver.

If you have the money for separates go for it!

 

[Swerd]

I guess it depends on the price for the B&K 507 receiver. I assume you will paythe online prices for the Emotiva separates.

The B&K receivers are quite a bit better than the typical receiver. I have heard that these receivers (505 and 507) have the same preamp/processor section that is sold separately as the Ref 50 preamp/processor, and that is very capable and good. The receivers have an amp section that delivers an honest 150 watts per channel - not too shabby.

Probably the best part of the B&K models is their extremely good bass management. They allow you to select a subwoofer crossover frequency any where between 20 and 200 Hz, and allow you to choose between several crossover slopes. In my opinion, the best feature is that once you have done the basic setup, it has the ability to generate test tones (from 20 to 300 Hz if I recall) to see what your system does in your room. Once you plot readings from SPL meter, you can create digitally, as many as 5 notch filters to equalize bass response in your room. For each notch filter, you select the filter's center frequency, the width of the filter, and it's amplitude. I have seen this in operation, and it allows you to significantly smooth the bass response in your room. Download the owner's manual and read the bass set up section.

I'm not familiar with the bass management details of the Emotiva preamp, but I doubt it is as capable as the B&K.

 

[kordon]

I guess it depends on the price for the B&K 507 receiver. I assume you will paythe online prices for the Emotiva separates.

The B&K receivers are quite a bit better than the typical receiver. I have heard that these receivers (505 and 507) have the same preamp/processor section that is sold separately as the Ref 50 preamp/processor, and that is very capable and good. The receivers have an amp section that delivers an honest 150 watts per channel - not too shabby.

Probably the best part of the B&K models is their extremely good bass management. They allow you to select a subwoofer crossover frequency any where between 20 and 200 Hz, and allow you to choose between several crossover slopes. In my opinion, the best feature is that once you have done the basic setup, it has the ability to generate test tones (from 20 to 300 Hz if I recall) to see what your system does in your room. Once you plot readings from SPL meter, you can create digitally, as many as 5 notch filters to equalize bass response in your room. For each notch filter, you select the filter's center frequency, the width of the filter, and it's amplitude. I have seen this in operation, and it allows you to significantly smooth the bass response in your room. Download the and read the bass set up section.

I'm not familiar with the bass management details of the Emotiva preamp, but I doubt it is as capable as the B&K.

Actually, I already own the B&K and was thinking the Emotiva would be an upgrade. I never could figure the bass management out.

 

[Swerd]

Actually, I already own the B&K and was thinking the Emotiva would be an upgrade. I never could figure the bass management out.

In that case, definitely keep the B&K receiver. With the parametric equalizer built-in the B&K receiver, you have the equivalent of a separate digital equalizer such as the Behringer Feedback Destroyer.

You never mentioned what speakers you use. If the B&K does not have enough power for them, you might get an external 2-channel amp to drive your main speakers, and use the B&K receiver to drive your center and surround channels. I don't think the Emotiva preamp/processor will make an audible improvement, but that's my opinion.

To use the B&K bass management, you need a SPL meter. Radio Shack sells them. Run through each of the bass test tones and write down the meter readings for each tone. If I remember, it does a test tone at 20, 22, 24, etc. up to 200 Hz. Keep the SPL meter in the same location as you do this. It helps if you have a camera tripod, but you can hand hold it.

Plot the results on graph paper, SPL reading in db (vertical axis) vs. Hz (horizontal axis). You will probably see several peaks and valleys in the response curve. Ignore the valleys and concentrate on the peaks.

Pick the tallest peak and create a notch filter centered on the peak's center frequency. Make the filter as wide as necessary and set the least amplitude (db quieting) needed to flatten the peak. You may have to do this by trial and error until you get right. Use the test tones and SPL meter to see the result of your changes. Then repeat those steps with the next tallest peak. You can filter up to 5 of the worst peaks this way. Many people have only 2 or 3. I would avoid using the equalizer to boost the response of a valley, but you could always try it and see what happens.

After you do this, you may find that the bass doesn't seem as loud as it was, but with the worst peaks flattened out, you have smoother sounding bass over a broader range. Often, people who have one or two large peaks in their bass response, set their bass volume so that they are only hearing those peaks, and not any where else in the bass range. This is the so called "one note bass" that many people describe.

 

[kordon]

In that case, definitely keep the B&K receiver. With the parametric equalizer built-in the B&K receiver, you have the equivalent of a separate digital equalizer such as the Behringer Feedback Destroyer.

You never mentioned what speakers you use. If the B&K does not have enough power for them, you might get an external 2-channel amp to drive your main speakers, and use the B&K receiver to drive your center and surround channels. I don't think the Emotiva preamp/processor will make an audible improvement, but that's my opinion.

To use the B&K bass management, you need a SPL meter. Radio Shack sells them. Run through each of the bass test tones and write down the meter readings for each tone. If I remember, it does a test tone at 20, 22, 24, etc. up to 200 Hz. Keep the SPL meter in the same location as you do this. It helps if you have a camera tripod, but you can hand hold it.

Plot the results on graph paper, SPL reading in db (vertical axis) vs. Hz (horizontal axis). You will probably see several peaks and valleys in the response curve. Ignore the valleys and concentrate on the peaks.

Pick the tallest peak and create a notch filter centered on the peak's center frequency. Make the filter as wide as necessary and set the least amplitude (db quieting) needed to flatten the peak. You may have to do this by trial and error until you get right. Use the test tones and SPL meter to see the result of your changes. Then repeat those steps with the next tallest peak. You can filter up to 5 of the worst peaks this way. Many people have only 2 or 3. I would avoid using the equalizer to boost the response of a valley, but you could always try it and see what happens.

After you do this, you may find that the bass doesn't seem as loud as it was, but with the worst peaks flattened out, you have smoother sounding bass over a broader range. Often, people who have one or two large peaks in their bass response, set their bass volume so that they are only hearing those peaks, and not any where else in the bass range. This is the so called "one note bass" that many people describe.

Wow, thats great information. Thank you. My speakers are PSB silveri's. I'm not sure what I'm unhappy about in my system to be honest. Although I now need HDMI.

 

[Swerd]

Wow, thats great information. Thank you. My speakers are PSB silveri's. I'm not sure what I'm unhappy about in my system to be honest. Although I now need HDMI.

I’m not familiar with those Silveris, the other PSB speakers I’ve heard are very good. They do well with high power.

While HDMI connections between a BR disc player and a HDTV with 1080p resolution are necessary, in a receiver, they are nice but are not required. I think it would be a waste if you discarded the B&K receiver with its ability to improve bass response in order to get the latest in bells & whistles.

The bass management and equalization that the B&K receiver does is not so much to correct for speaker problems, but to correct for acoustic problems caused by the rooms we keep our speakers in. Bass tones have wavelengths long enough (100 Hz is 11.3 feet, 50 Hz is 22.6 feet, etc.) that the primary sound from speakers combines with reflections off walls, floor and ceiling within a room to create standing wave patterns. This results in areas within a room where bass tones are either too loud or too quiet. This occurs primarily below 200 Hz. It is a very common problem and can happen with any speaker. A digital parametric equalizer (such as in the B&K receiver) is an easy and very effective solution for this problem. Try it. It will only cost you about $50 for a SPL meter from Radio Shack or Amazon.

If you don’t like the results, you can always return the settings to their default values.

Others attempt to treat their rooms with acoustic absorption panels or bass traps on the walls or in the corners of their rooms. Although this can also be effective, you have to know what you are doing, it can get expensive, and it often results in a room with unacceptable appearance.

 

[kordon]

I’m not familiar with those Silveris, the other PSB speakers I’ve heard are very good. They do well with high power.

While HDMI connections between a BR disc player and a HDTV with 1080p resolution are necessary, in a receiver, they are nice but are not required. I think it would be a waste if you discarded the B&K receiver with its ability to improve bass response in order to get the latest in bells & whistles.

The bass management and equalization that the B&K receiver does is not so much to correct for speaker problems, but to correct for acoustic problems caused by the rooms we keep our speakers in. Bass tones have wavelengths long enough (100 Hz is 11.3 feet, 50 Hz is 22.6 feet, etc.) that the primary sound from speakers combines with reflections off walls, floor and ceiling within a room to create standing wave patterns. This results in areas within a room where bass tones are either too loud or too quiet. This occurs primarily below 200 Hz. It is a very common problem and can happen with any speaker. A digital parametric equalizer (such as in the B&K receiver) is an easy and very effective solution for this problem. Try it. It will only cost you about $50 for a SPL meter from

If you don’t like the results, you can always return the settings to their default values.

Others attempt to treat their rooms with acoustic absorption panels or bass traps on the walls or in the corners of their rooms. Although this can also be effective, you have to know what you are doing, it can get expensive, and it often results in a room with unacceptable appearance.

Definitely going to give this a go. Through your posts I hope to figure this out. Does this just change how bass sounds or does it improve the entire listening experience? So much emphasis on bass management, what am I missing?

 

[Swerd]

Definitely going to give this a go. Through your posts I hope to figure this out. Does this just change how bass sounds or does it improve the entire listening experience? So much emphasis on bass management, what am I missing?

Good. I hope you get it to work. Once you work through the procedure, its not as difficult as it sounds. It is harder to explain all this than it is to do it.

This changes how bass sounds. It will not have a direct effect on other frequencies. I probably overloaded you with info, but reflections off of walls, floor & ceiling have the worst effect on bass below 200 Hz. Above 200 Hz, most room reflections are a much smaller problem.

Let us know how things progress with this .