| Nonox |
Hello, I have a pair of B&W 800 Matrix witch ask a lot of current.
I would like to know if the Nakamichi PA-7E poweramp coud drive well the b&w's.
this amp has been disigned by Nelson Pass and was made during end of the 80's.
The power is always mentioned in 8 Ohms (200W) but never in 4 Ohms.
Does this means that it doesn't handle well 4 Ohms speakers or just that they didn't mentioned the power in 4 Ohms?
Thank you
Bruno |
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| Netlist |
The recommended power output for the amplifier is between 150w min. and 800w max. into 8 ohm but I found out that the 800 matrix is not at all demanding on amplifiers.
They take about anything, and are very rewarding once you start using better gear.
I'm currently driving them with a pair of AlephX's and I'm very pleased.
/Hugo |
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| sourceoneaudio |
Nakamichi PA-7 amps will run into a 4ohm load. I have a factory piece literature stating that the output is 500 per channel into 4ohms. Here are the factory specs for you to look over.
Dimensions: 17-1/8 (W) X 7-7/8 (H) X 16-9/96 (D) inches Approximate weight: 59 lbs., 8 oz
Continuous Average Power Output (NEW IHF): 200W x 2 (8 ohms, both channels driven, 20-20,000 Hz, 0.1% THD) Dynamic Power per Channel: 300 W (8 ohms) Dynamic Head Room (NEW IHF): 1.7 dB (8 ohms) Power Bandwidth (Half Rated Power, 0.1% Damping Factor: (NEW IHF) 20 Hz/1 kHz/20 kHz: Greater than 60/60/60
Input Sensitivity/Impedance (NEW IHF): 2.0 V/ 75k ohms (rated power) 140 mV (1W output)
Frequency Response: (1 W, NEW IHF): 20-20,000 Hz + 0, -0.5 dB, 7-150,000 Hz +0, -3 dB
Signal to Noise Ratio (Input Shorted, Rated Power, IHF A-WTD) : Better than 120 dB Residual Noise Level (IHF A-WTD): Less than 25 u V/
Total Harmonic Distortion: Less than 0.1%
Intermodulation Distortion: Less than 0.1%
Stereo Separation (Input Shorted): 110/100/80 dB
Output Complement: 16 Transistors Per Channel
Output Current Capability: 18 A continuous, 50 A peak (per channel)
Power Supply: 700 W toroidal transformer, 132, 000 u F total filter capacitance
Power Source: 120, 220, 240 or 110-120/220-240 V AC; 50/60 Hz,
Power Consumption: 700 W max.
Hope this helps, J/S-S1A |
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| twolf5 |
FWIW, I happened to visit Nakamichi America in Torrance, CA in the late 80's (dropping off my OMS 7 for repair) and saw an all Nakamichi 7 series (PA 7, CA 7, OMS 7, ST 7) system in the main lobby with B&W 800 Matrix speakers. It was an enviable system then but it was not turned on! I quickly left to find the repair entrance, but I do believe at one point, the PA 7 brochure featured an outline of the B&W 800 Matrix speaker. Not an official endorsement, of course, but more than coincidence I am sure.
twolf5 |
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| Nelson Pass |
The Nakamichi build was pretty beefy in the output
stage and power supply, so I wouldn't have any
doubts about the 4 ohm performance.
:cool: |
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| rolfez |
My Vienna Beethoven speakers are rated 4 ohms and even dips to 2.5 ohms in the upper bass I think. My PA5EII is very happy driving these and will even melt voice-coils on woofers on occasion so don't worry about the PA7 running on 4 ohms.
Regards
Rolf |
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| Stefanoo |
am i wrong by saying that B&W800 are 8ohm?
They are great!
I believe that they shouldn't be as demaning in current as you think they are (differently from the 805 indeed).
They only ask you for a very good and neutral amplification system...that's all!
You ' ll find them to sound Veeeeery different upon the type of amp they are plugged on.
enjoy your speakers. |
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