B&W 802d

[English210]

IT does show a dynamic headroom rating of 2db, and that's what's being used during peaks. I'll leave it to the numbers guys to translate that into (for example) available output at 3.67ohms (?)

 

[English210]

You in Florida?

Who? Me? I'm in GA

 

[flyboylr45]

Yea. I'll keep the Focals ready for you to pick up.

 

[PENG]

IT does show a dynamic headroom rating of 2db, and that's what's being used during peaks. I'll leave it to the numbers guys to translate that into (for example) available output at 3.67ohms (?)

For power calculations:

2dB above rated is 10^(2/10) 1.585X rated

3dB is 1.995X or rounded to 2X

 

[PENG]

Yea. I'll keep the Focals ready for you to pick up.

To me the 802 diamond trumps the 1028 only in bass. 1028 plus two nice subs will trump the 802 diamond but it is a highly subjective thing. I do prefer the 802 because I like the look of the Marlan head.

 

[PENG]

Let's round UP to 3m then. 100dB peak from TWO speakers = 97dB from one speaker = 45W into 8 ohms or 90W into 4 ohms.

103dB peak from 2 speakers = 100dB from one speaker = 90W into 8 ohms or 180W into 4 ohms.

104dB peak from 2 speakers = 113W/8 ohms or 226W/4 ohms.

105dB peak = 143W/8 ohms or 286W/4 ohms.

106dB = 180W/8 or 360W/4 ohms.

We are missing something here. I thought he meant 100 dB average then it would make sense for his VU meters to show averages of >100W with peaks approaching the 250W mark. Given that those VU meters are not really capable of indicating the absolute highest peaks, I would think his real peaks would be a little more than 250W, but that also depends on the impedance of the load during the highest peaks because the meters are typically calibrated for 8 ohm loads.

Now if he meant 100 dB "peaks" as he seems to be saying now, then as your math shows, at 100 dB peak he would need 90W (approx of course) into 4 ohms. So why were the meters showing peaks of 250W? That does not come close to 90W even if you mentally recalibrate the VU meters to lower or higher impedance.

At the end of the day I tend to go with the meters, and would therefore conclude that a larger amp won't hurt, though likely not required.

 

[PENG]

I looked at flyboy's video again and it does seem like his minimum was around 25W and maximum just under 250. Allowing the the missing min/max due to meter response time etc., the dynamic range of that piece of music wasn't great, like 9 dB min to max and less than 3 dB average to peak. If he listens to music that has DR of 12 to 20 dB then the predictable outcome could be:

a) If we define DR as min to peak and min is still around 25W, then the amp will be pumping out 400W during the peak swings.

b) If DR is defined as average to peak (online DR tables seem to go with that definition), and assuming the average is around 100W and that would seem low judging from that video, the amp would have to pump out 1600W during the peak swings.

Above scenarios could be realized if he plays most Diana Krall kind of jazz (CD/SACD).

The MA7000 is probably one of those that use autotransformer with impedance tap setting so the 8,4,2 ohm outputs are rated similar, but most likely could handle peaks of at least 500 to 600W without audible distortion but anything more than that it would be in more major clipping territory with THD >1% I would think.

 

[English210]

To me the 802 diamond trumps the 1028 only in bass. 1028 plus two nice subs will trump the 802 diamond but it is a highly subjective thing. I do prefer the 802 because I like the look of the Marlan head.

I haven't spent any time with the 802D2, so I'll take your word for it, but I can't fit them in the room anyway, and my wife isn't wild about the Marlin head, so it's a non-starter.

Sounds good flyboylr45, I'll try to narrow down which rich uncle is going to provide the means

 

[AcuDefTechGuy]

Macs don't increase as ohms drop (that's the way I understand it). It's 250 watts at 8, 4, or 2 ohms. Right now, I have them hooked up to the 4 ohm tap on the Ma7000.

Acudef, I have no idea what you wrote means. The only thing I gather is that the lowest the 802s will drop to is 3.67ohms.

Impedance, sensitivity, & phase angel help determine how difficult it is to power your speakers.

For example, a speaker with an impedance of < 4 ohms, phase angle of +/- 60 degrees, and sensitivity of 85dB/2.83v/m will be quite difficult to power, especially in 2.0 direct mode and at higher volume > 100dB and farther distance > 4m.

But I'm with PENG. I would go with the UV meters. If it says you are using 250W peak, then I would use a 250-300W amp.

 

[AcuDefTechGuy]

To me the 802 diamond trumps the 1028 only in bass. 1028 plus two nice subs will trump the 802 diamond but it is a highly subjective thing. I do prefer the 802 because I like the look of the Marlan head.

"The 1028 Be’s listening-window response (a five-point average of axial and +/–15-degree horizontal and vertical responses) measures +1.75/–1.84 decibels from 200 hertz to 10 kilohertz. The –3-dB point is at 48 Hz, and the –6-dB point is at 41 Hz. Impedance reaches a minimum of 3.72 ohms at 403 Hz and a phase angle of +48.30 degrees at 812 Hz."

"The 802 Diamond’s listening-window response (a five-point average of axial and +/–15-degree horizontal and vertical responses) measures +2.82/–2.79 decibels from 200 hertz to 10 kilohertz. The –3-dB point is at 31 Hz, and the –6-dB point is at 27 Hz. Impedance reaches a minimum of 3.67 ohms at 98 Hz and a phase angle of –54.11 degrees at 49 Hz."

Yep, more bass from towers.

I prefer bass from subs.

 

[English210]

"The 1028 Be’s listening-window response (a five-point average of axial and +/–15-degree horizontal and vertical responses) measures +1.75/–1.84 decibels from 200 hertz to 10 kilohertz. The –3-dB point is at 48 Hz, and the –6-dB point is at 41 Hz. Impedance reaches a minimum of 3.72 ohms at 403 Hz and a phase angle of +48.30 degrees at 812 Hz."

"The 802 Diamond’s listening-window response (a five-point average of axial and +/–15-degree horizontal and vertical responses) measures +2.82/–2.79 decibels from 200 hertz to 10 kilohertz. The –3-dB point is at 31 Hz, and the –6-dB point is at 27 Hz. Impedance reaches a minimum of 3.67 ohms at 98 Hz and a phase angle of –54.11 degrees at 49 Hz."

Yep, more bass from towers.

I prefer bass from subs.

But you prefer the 802D2's...?

 

[AcuDefTechGuy]

But you prefer the 802D2's...?

4 things.

1) I prefer the aesthetic of the 802D2 over all other speakers on the planet regardless of price.
2) I prefer the name "B&W" over "Focal". I mean "B&W" just sounds so much cooler. It sounds like "BMW". I mean C'mon now.
3) I can also use my seven samurai subs with the 802D2.
4) I'm out of control.

 

[haraldo]

4 things.

1) I prefer the aesthetic of the 802D2 over all other speakers on the planet regardless of price.
2) I prefer the name "B&W" over "Focal". I mean "B&W" just sounds so much cooler. It sounds like "BMW". I mean C'mon now.
3) I can also use my seven samurai subs with the 802D2.
4) I'm out of control.

How can you argue with such a reasoning?

 

[AcuDefTechGuy]

How can you argue with such a reasoning?

It's utterly unassailable. I mean I really know my priority here.

 

[haraldo]

It's utterly unassailable. I mean I really know my priority here.

I would pick British over French.... too

 

[AcuDefTechGuy]

I would pick British over French.... too

Oh, most definitely. That was number 5.

 

[English210]

I would pick British over French.... too

Why didn't I think of that??? THAT is unassailable logic!!

I like the 802D2s cosmetically as well, but SWMBO does not, and in truth, the room isn't big enough. I do like the 803D2, however, and British-over-French argument in hand, I may have to reconsider BMW in the driveway, B&W in the family room.

Hey, it's no crazier than some buying determining factors I've heard...

 

[flyboylr45]

BTW, they're here!!!! Santa came early for me.



http://i1291.photobucket.com/albums/b557/andybernal/20131210_182012_zps064f53fe.jpg

 

[charmerci]

Impedance, sensitivity, & phase angel help determine how difficult it is to power your speakers.

Before I make a decision on buying new stereo equipment, I pray to my phase angel for help!

 

[PENG]

Why didn't I think of that??? THAT is unassailable logic!!

I like the 802D2s cosmetically as well, but SWMBO does not, and in truth, the room isn't big enough. I do like the 803D2, however, and British-over-French argument in hand, I may have to reconsider BMW in the driveway, B&W in the family room.

Hey, it's no crazier than some buying determining factors I've heard...

So logically French210 would automatically pick the 1028?