shadders
Well-known member
Hi,Artoo said:shadders said:Hi,Electro said:shadders said:Hi,Electro said:TrevC said:I have never heard an Abrahamson, but if it's anything like his silly god he can keep his amplifiers.
OK, I looked them (Abrahamsen) up. Made in China stuff, looks pretty so will automatically 'sound' good in sighted testing. Unfortunately they also market foo wire, a major negative in terms of credibility IMO. I have never heard any, but then I only ever hear stuff that goes faulty.
Abrahamsen amplifiers are all made in Sweden and it is unlikely that you will ever hear an Abrahamsen amp in that case .
The technical spec is far beyond anything near the price with a 1000va transformer , 100 amps of peak current delivery and transient power measured in kilowatts.
http://www.iqspeakers.co.uk/#!abrahamsen/ckbj
Is that 100amps per channel, or from the power supply? I examined the Web site and it seems that there are 3 power transistors per positive or negative swing of the waveform. I am not sure each could withstand 33.3amps each, even as a transient.
Regards, Shadders.
There are a total of 12 output transistors .
there are 6 transistors per channel, where only 3 conduct at one time per channel. Assuming each channel is on the positive swing then each transistor will have to conduct 16.65amps each to achieve the 100amps quoted.
From the website picture, the transistors are Toshiba 2SC3421 which have a peak continuous current capability of 1amp, and not 16.65amps. Pulse capability is 2 amps maximum, and safe operating is 3 amps for a one off pulse. This equates to 5 times less than shared 100amps/6=16.65amps.
i believe that numbers quoted by people or manufacturers need to be reviewed and understood. The 100amps quoted sounds very impressive, yet the output relay has a maximum capability of 16amps.
One channel has a maximum peak output of 9 amps (based on transistors) as a single non repeatable transient.
Or 6amps as a repeated pulse on the output.
Or 3amps continuous per channel, which is 6amps continuous per amplifier (both channels).
Much less than the quoted 100amps.
Regards,
Shadders.
Interesting. If you have the time, could you please look into the Hegel H80 and see how it compares to the Abrahamsen?
Cheers!
a quick scan shows that the Hegel H80 uses two output transistors per channel, one for the positive and one for the negative voltage swing. The transistors from the picture are Toshiba 2SA2121/5949 - seem to be a complimentary pair. They have a continuous current capability of 15amps. This on paper is 5x the output capability (continuous) per channel, in comparison to the Abrahamsen. The issue is that the transformer used as per pictures (not the manufacturers website) is 250VA. Without knowing the power supply capacitance, it is difficult to determine any limitations.
This is where actual performance tests conducted by Hifi magazines are very helpful, as they will provide peak current capability as measured, and not based on those parameters which present the device/equipment in the best light, where those parameters could never be used in the real world.
Example, Abrahamsen has a continuous output current of 3amps, whereas the Hegel H80 has a continuous output current of 15amps. But this is on paper, and I expect the Hegel to be less than this, but the figures I have quoted for Abrahamsen are accurate IF the pictures on iqspeakers website are correct.
Regards,
Shadders.