In Reply to: Atmasphere MA-2 impedance question posted by earlinarizona@cox.net on June 1, 2012 at 18:33:39:
At 60 ohms the MA-2 does loose some power but its not a lot. Above about 5 ohms, the amp is on a linear curve where power is decreasing very slightly as impedance is increased, such that at 16 ohms the amp makes the same power it does into 4 (we are only talking a couple of watts here). The limitation is the voltage in the power supplies of the amp, but essentially what happens is into the higher impedances the output section also gets more efficient- more power dissipated in the load and less into the power tubes. So on a Sound Lab the MA-2s (and MA-1s) tend to run with less heat, with no trouble making bass power, something that is a problem with many amps, especially transistor amps (although transformer-coupled tube amps can be challenged by the impedance curve as well).
The result is that the MA-2 can make the same volume on the speaker as transistor amps rated at 600-800 watts.
The Sound Lab mods that have been a topic on this forum seem to really help the amp out, regardless of the amplifier technology. Customers that have MA-2s and Sound Labs that have done just the resistor mod alone report that they essentially have unlimited power- its not possible to clip the MA-2s. That means that the actual panels themselves must be fairly efficient- well into the 90s by equivalent 1 watt/1 meter measurement.
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Follow Ups
- RE: Atmasphere MA-2 impedance question - Ralph 09:47:52 06/04/12 (54)
- RE: Atmasphere MA-2 impedance question - roio 12:55:58 09/05/14 (0)
- OK now I am totally confused... - Penguin 19:58:25 06/04/12 (52)
- RE: OK now I am totally confused... - KIS 05:32:31 06/07/12 (20)
- do you have your speakers wired for bi-amping? - Penguin 21:31:38 06/07/12 (19)
- RE: do you have your speakers wired for bi-amping? - KIS 23:19:34 06/07/12 (18)
- I think it is pretty obvious :) - Penguin 07:02:04 06/08/12 (17)
- RE: I think it is pretty obvious :) - tyu 08:12:04 06/08/12 (16)
- I think one of my backplates is wired wrong.... - Penguin 11:57:39 06/10/12 (14)
- RE: I think one of my backplates is wired wrong.... - Lew 13:59:02 06/10/12 (13)
- ok, ok, ok.... - Penguin 20:15:09 06/10/12 (12)
- What does it sound like? Do you have a damaged panel? nt - Ralph 08:12:57 06/11/12 (9)
- I will check tonight - Penguin 09:46:06 06/11/12 (8)
- It is official it is the panel - Penguin 13:57:43 06/11/12 (7)
- RE: It is official it is the panel - Lew 12:02:17 06/12/12 (5)
- One interesting thing.... - Penguin 12:27:44 06/12/12 (3)
- RE: One interesting thing.... - Lew 14:13:12 06/12/12 (1)
- RE: One interesting thing.... - Penguin 21:54:48 06/12/12 (0)
- RE: One interesting thing.... - tyu 13:25:45 06/12/12 (0)
- I always wanted a good excuse to have them re-mylared - Penguin 12:10:39 06/12/12 (0)
- the day is Monday :) - Penguin 12:00:37 06/12/12 (0)
- RE: ok, ok, ok.... - Lew 07:36:29 06/11/12 (1)
- RE: ok, ok, ok.... - Penguin 09:44:41 06/11/12 (0)
- ok... - Penguin 10:21:53 06/08/12 (0)
- RE: OK now I am totally confused... - Lew 07:01:19 06/05/12 (29)
- RE: OK now I am totally confused... - tyu 09:37:42 06/05/12 (0)
- RE: OK now I am totally confused... - Ralph 08:56:55 06/05/12 (27)
- I tried it with a 24uF cap and sounded horrible - Penguin 18:12:52 06/06/12 (15)
- RE: I tried it with a 24uF cap and sounded horrible - Lew 15:01:14 06/07/12 (2)
- I did not try it with the MA1 - Penguin 20:01:49 06/07/12 (1)
- taking just the resistor did not work - Penguin 21:24:44 06/07/12 (0)
- RE: I tried it with a 24uF cap and sounded horrible - Ralph 07:46:55 06/07/12 (11)
- Very distorted on bass and transients like an amp clipping - Penguin 08:44:19 06/07/12 (10)
- RE: Very distorted on bass and transients like an amp clipping - Ralph 10:16:31 06/07/12 (9)
- Not the removal of cap:) - Penguin 12:42:00 06/07/12 (8)
- RE: Not the removal of cap:) - Ralph 14:41:52 06/07/12 (7)
- exactly.... - Penguin 20:12:26 06/07/12 (6)
- RE: exactly.... - Ralph 08:48:45 06/08/12 (5)
- hmmm - Penguin 10:32:03 06/08/12 (4)
- Another way to think of it - Lew 22:54:30 06/08/12 (2)
- or just simply - Penguin 08:19:51 06/09/12 (1)
- RE: or just simply - tyu 08:53:15 06/09/12 (0)
- RE: hmmm - Ralph 11:45:56 06/08/12 (0)
- RE: OK now I am totally confused... - Lew 12:35:34 06/05/12 (10)
- I was using a different chart - Ralph 13:49:13 06/05/12 (9)
- RE: I was using a different chart - Lew 19:18:09 06/05/12 (8)
- RE: I was using a different chart - Ralph 09:07:15 06/06/12 (7)
- RE: I was using a different chart - Lew 06:56:24 06/07/12 (6)
- RE: I was using a different chart - Ralph 07:51:46 06/07/12 (2)
- RE: I was using a different chart - Lew 14:55:45 06/07/12 (1)
- RE: I was using a different chart - Ralph 08:41:04 06/08/12 (0)
- RE: I was using a different chart - KIS 07:31:47 06/07/12 (2)
- RE: I was using a different chart - Lew 14:51:35 06/07/12 (1)
- RE: I was using a different chart - Ralph 09:22:17 06/08/12 (0)
- RE: OK now I am totally confused... - tyu 04:31:00 06/05/12 (0)