I would take it that 43 Hz would be the F3 point given the +/- 3dB spec.
This means the speaker could be making 92dB at 43Hz @1 watt - meter.
Seems a stretch for a 6-1/2 driver and a box volume of around .6-.7 Cu/Ft
Klipsch RB-61 Bookshelf Speaker
Specifications
FREQUENCY RESPONSE 43Hz-23kHz +/-3dB
POWER HANDLING 100W RMS / 400W Peak
SENSITIVITY 95dB @ 2.83V / 1m
NOMINAL IMPEDANCE 8 ohms compatible
HIGH FREQ CROSSOVER 2000Hz
HIGH FREQUENCY DRIVERS 1" (2.54cm) Titanium diaphragm compression driver mated to 90x60 square Tractrix® Horn
LOW FREQUENCY DRIVERS 6.5" (16.5cm) Cerametallic™ cone woofer
ENCLOSURE TYPE Bass-reflex via front-firing port
HEIGHT 15.4" (39.1cm)
WIDTH 8.5" (21.6cm)
DEPTH 12.25" (31.1cm)
WEIGHT 22lbs (10kg)
FINISHES Cherry or Black Ash woodgrain vinyl
This means the speaker could be making 92dB at 43Hz @1 watt - meter.
Seems a stretch for a 6-1/2 driver and a box volume of around .6-.7 Cu/Ft
Klipsch RB-61 Bookshelf Speaker
Specifications
FREQUENCY RESPONSE 43Hz-23kHz +/-3dB
POWER HANDLING 100W RMS / 400W Peak
SENSITIVITY 95dB @ 2.83V / 1m
NOMINAL IMPEDANCE 8 ohms compatible
HIGH FREQ CROSSOVER 2000Hz
HIGH FREQUENCY DRIVERS 1" (2.54cm) Titanium diaphragm compression driver mated to 90x60 square Tractrix® Horn
LOW FREQUENCY DRIVERS 6.5" (16.5cm) Cerametallic™ cone woofer
ENCLOSURE TYPE Bass-reflex via front-firing port
HEIGHT 15.4" (39.1cm)
WIDTH 8.5" (21.6cm)
DEPTH 12.25" (31.1cm)
WEIGHT 22lbs (10kg)
FINISHES Cherry or Black Ash woodgrain vinyl
Let's have a closer look.
95 dB at 2.83V and 8 ohms. If memory serves me correctly that means 92 dB a 1 watt. + or - 3 dB means a swing of 6. So if they fudge a little and use a point where it's closer to the +3 when give you the sensitivity rating that means we can lose that 6dB at the low end. So no, you're not likely to get 92 dB at one watt at 43Hz, you're more likely to get around 86dB.
And that's on a good day.
95 dB at 2.83V and 8 ohms. If memory serves me correctly that means 92 dB a 1 watt. + or - 3 dB means a swing of 6. So if they fudge a little and use a point where it's closer to the +3 when give you the sensitivity rating that means we can lose that 6dB at the low end. So no, you're not likely to get 92 dB at one watt at 43Hz, you're more likely to get around 86dB.
And that's on a good day.
Let's have a closer look.
95 dB at 2.83V and 8 ohms. If memory serves me correctly that means 92 dB a 1 watt. + or - 3 dB means a swing of 6. So if they fudge a little and use a point where it's closer to the +3 when give you the sensitivity rating that means we can lose that 6dB at the low end. So no, you're not likely to get 92 dB at one watt at 43Hz, you're more likely to get around 86dB.
And that's on a good day.
..and even that is probably an in-room estimate.
Look *deeply* in to my marketing -
.. You will now believe everything we communicate to you. ...speaker in the corner, hardwood floors, no furniture
Well, I'm building a pair of ported speakers with 1.5 Cu. Ft. and 10" drivers matched to it. F3 will be 50Hz. If Klipsch can pull of that miracle, I can stop building these.
I wish speaker specifications were regulated like audio power output claims are. So why aren't they?
Well, I'm building a pair of ported speakers with 1.5 Cu. Ft. and 10" drivers matched to it. F3 will be 50Hz. If Klipsch can pull of that miracle, I can stop building these.
I wish speaker specifications were regulated like audio power output claims are. So why aren't they?
You could have said that about power amp specs in the 70's. At least regulations give you some idea of true power now.
Regarding those specifications it probably is a significant stretch driven by the guys in marketing, but I have always been of the impression that Klipsch was reputable. Certainly earlier Klipsch speakers measured by my former employer as a comparative baseline of competitor performance at a given price point (sorry for the mouthful.. ) actually met their published specs within reasonable limits of experimental accuracy.
I am not sure exactly how the company is run since Paul Klipsch died, so I can't say that they still do things the way they used to.
So much idle speculation, perhaps someone with a pair of RB-61 would be willing to test them to see?
) actually met their published specs within reasonable limits of experimental accuracy.I am not sure exactly how the company is run since Paul Klipsch died, so I can't say that they still do things the way they used to.
So much idle speculation, perhaps someone with a pair of RB-61 would be willing to test them to see?
I don't follow. 2.83 volts is 1 watt into an 8 ohm load, so why the -3 dB?
95 dB at 43 Hz! My 15 inch Summa can't do that honestly, so I guess that I'd be suspicious of those claims. But heck, this is audio, you can't believe much of what you read.
specs are for sales
In the sixties and seventies when botique audio salons were still open with "listening rooms", I noticed that Radio Shack's specs were as good as anybody's, but there stuff sounded like ****. They were close and had long hours, I bought some things anyway. One of their manuals let the secret slip- in addition to the regular good looking numbers, at the bottom there was a production tolerance- which was so wide even they probably could have met it. I think the product was earphones.
Nobody makes anybody publish the production tolerance. Some manufactures have names and know people check up on them, like Tektronix and Fluke. Other manufacturers are in the consumer audio business.
In the sixties and seventies when botique audio salons were still open with "listening rooms", I noticed that Radio Shack's specs were as good as anybody's, but there stuff sounded like ****. They were close and had long hours, I bought some things anyway. One of their manuals let the secret slip- in addition to the regular good looking numbers, at the bottom there was a production tolerance- which was so wide even they probably could have met it. I think the product was earphones.
Nobody makes anybody publish the production tolerance. Some manufactures have names and know people check up on them, like Tektronix and Fluke. Other manufacturers are in the consumer audio business.
See what happens when you get older?
Thanks for clearing that up Earl.
This is why I don't give the +/- 3db claim any thought. It's bunk. Now there are some who are making wild claims about +/- 1.5db. For an array of cone transducers? Nah. Go ahead, measure them yourself without 'smoothing' them or any other nonsense. If you can find +/- 6db I think that's excellent.
You might be on to something there. Even if they put 1 watt into 4 ohm (parallel the speakers), you'll get +3dB because of the cone area increase. If you went to 2.83v into 4 ohm, you'll get 2 watts out, giving an increase of +6dB overall.
Someone mentioned a peak in response bringing up the efficiency. That's likely true. Even Eminence does it.
Perhaps they tuned the port to give a big peak at 50Hz, then 40Hz wouldn't be too far down.
Chris
Someone mentioned a peak in response bringing up the efficiency. That's likely true. Even Eminence does it.
Perhaps they tuned the port to give a big peak at 50Hz, then 40Hz wouldn't be too far down.
Chris
If those specs are real, I'll take five of them right now. Of course if you ever heard these things, you'd probably pass on them in a couple seconds. I did anyway. An absolute assault on my auditory system. I bought a set of Klipsch years ago b/c I thought big sound was essential. Well, I do find it essential, but not by any means.
Dan
Dan
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