what receiver will power these speakers

jamelfizzle -- Tue, 12/28/2010 - 10:37

i need to know a good receiver or what is needed to power these speakers...

BP-8080ST :Specifications

Dimensions (cabinet only, no stablizer feet) :48-14" H x 7" x 16-5/16" D | 122.5cm H x 17.8cm W x 41.3cm D
Dimensions (with stabilizer feet) :48-1/4" H x 12-1/8" x 16-5/16" D | 122.5cm H x 30.8cm W x 41.3cm D
Driver complement :3 each 5-1/4" (13cm) BDSS midrange drivers, 2 each 1" (25mm) aluminum dome tweeters, 1 each 12" (30cm) active subwoofer driver pressure coupled to 2 each 12-1/2" (32cm) Low-bass radiators
Frequency response :18Hz - 30kHz
Sensitivity :92 dB
Nominal impedance :8 Ohms
Recommended amplifier power :20 - 400 Watts
A/V Receiver Crossover Setting :Large, full bandwidth
Internal amplifier power :455 watts
Auto On / Off : :Signal Sensing
Power Requirements :110 volts A/C (product not available outside of USA, Canada and Latin America)
Inputs :One pair of 5 way binding posts; One LFE input (optional)
Accessories : :Stabilizer feet; carpet spikes, hard floor glides
Weight :66 lbs. 30kg

OR...

BP7000SC :Specifications

Dimensions | Metric :8-15/16" W x 16-5/8" D x 52-1/2" H | 22.7 x 42.2 x 133.4 cm
Driver Complement :Two 1" pure aluminum dome tweeters; Four 6-1/2" high definition upper bass/midrange drivers; One 14" long-throw subwoofer pressure coupled to two 14" Low Bass radiators.
Frequency Response :11 Hz - 30 kHz
Impedance :Compatible with 8 Ohms outputs
Sensitivity :92 dB
Recommended Associated Amplifier Power :20 - 1000 watts
Internal Amplifier Power :1800 watts
A/V Receiver Crossover Setting :Large; Full Bandwidth
Auto On / Off :Signal Sensing (US) | Signal Sensing and Switched (International)
Power Requirements :110 volts Alternating Current (US) | 220 volts Alternating Current (International)
Inputs :Two pairs of 5 way binding posts: Biwireable; One LFE input (optional)
Fuse :8 amp 250 volt Slo Blo (US) | 4 amp 250 volt Slo Blo (International)
Accessories :Stabilizer Bars; Feet; Isolation Spikes
Available Finishes :Piano-Gloss Black
Packaging :One to a carton
Weight | Metric :150 lbs | 68.0 kg
Warranty :5 Years; 3 Years for Amplifiers

Steven Stone -- Tue, 12/28/2010 - 10:42

92 dB is pretty efficient, so sensitivity shouldn't be an issue.

Unfortunately the impedance doesn't tell me much. The high/low impedance points and nominal load would be far more useful in determining if the speaker is an easy to drive load or not.

Also, obviously, the size of your room and how loud is loud for you makes a big difference as to what sort of power capacity you need.

Steven Stone
Contributor to The Absolute Sound, EnjoytheMusic.com, Vintage Guitar Magazine, and other fine publications

jamelfizzle -- Tue, 12/28/2010 - 10:47

ok. here are the links to the 2 speakers. i would be very happy and relieved if you could even pick out the receiver/amp that i need to buy...

BP7000SC-http://www.definitivetech.com/Products/products.aspx?path=Floor-Standing%20Speakers&productid=BP7000SC

BP8080ST-http://www.definitivetech.com/Products/products.aspx?path=Floor-Standing%20Speakers&productid=BP-8080ST

Steven Stone -- Tue, 12/28/2010 - 11:34

I can't do that.

But I can recommend downloading hard copies of the specs and bringing them to a a local shop that has receivers and seeing what they suggest.

I would look at offerings from Rotel, NAD, and Creek as possible candidates.

Mullard EL34 -- Mon, 01/03/2011 - 08:35

One of the reviews for the BP7000SC posted on the Definitive Audio Web site (http://www.definitivetech.com/documents/articles/BP7000SC_HT1003.pdf) has additional test measurement results:

HT Labs Measures: Definitive Technology BP7000SC SuperTower
Speaker System
This graph shows the quasi-anechoic (employing close-miking of all woofers)
frequency response of the BP7000SC L/R (purple trace), C/L/R3000 center
channel (green trace), and BPVX/P surround (red trace). All passive loudspeakers
were measured at a distance of 1 meter with a 2.83-volt input
and scaled for display purposes.
The BP7000SC’s listening-window response (a five-point average of
axial and +/–15-degree horizontal and vertical responses) measures
+2.50/–3.64 decibels from 200 hertz to 10 kilohertz. The –3dB point is at
22 Hz, and the –6dB point is at 21 Hz. Impedance reaches a minimum of
2.92 ohms at 424 Hz and a phase angle of –37.82 degrees at 154 Hz.
Sensitivity averages 91 dB from 500 Hz to 2 kHz.
The C/L/R3000’s listening-window response measures +2.39/–1.43 dB
from 200 Hz to 10 kHz. An average of axial and +/–15-degree horizontal
responses measures +2.73/–1.65 dB from 200 Hz to 10 kHz. The –3dB
point is at 37 Hz, and the –6dB point is at 33 Hz. Impedance reaches a
minimum of 2.16 ohms at 310 Hz and a phase angle of –33.93 degrees at
170 Hz. Sensitivity averages 93.5 dB from 500 Hz to 2 kHz.
The BPVX/P’s three-face averaged response measures +3.42/–3.02 dB
from 200 Hz to 10 kHz. The –3dB point is at 38 Hz, and the –6dB point
is at 35 Hz. Impedance reaches a minimum of 2.73 ohms at 457 Hz
and a phase angle of –47.74 degrees at 224 Hz. Sensitivity averages
91 dB from 500 Hz to 2 kHz.—AJ

So, while the speaker has a moderately high sensitivity, the measured minimum impedance values indicate that you'll need a power-amplifier with a fairly stout current-delivery capacity to effectively drive these speakers. Steven's recommendations about consulting an audio dealer who carries Rotel, NAD, and/or Creek seems like an excellent approach to locating a rational high-end receiver to match-up with the speakers.