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Title: Arc Prediction & high-bandwidth amp - a disaster waiting to happen? Post by: manisandher on August 25, 2011, 09:29:58 pm Continuing with my 'super-fast amplifier' saga, something has occurred to me.
Some of the highest bandwidth amps around are from Spectral. Now, Spectral are totally adamant that you need to use a Spectral preamp and Spectral/MIT interconnects with their power amps. The warranty is void if you do not do this. The reasoning here is that the power amp has a bandwidth of DC-3MHz. It will amplify any ultra-high-frequency signal/noise that enters it. The Spectral preamp and the Spectral/MIT cables ensure that all ultra-high-frequency signals are filtering out before reaching the power amp. You may ask why Spectral don't just lower the bandwidth of their amps then. Well, this would reduce their speed/slew-rate. So by having a high bandwidth, but filtering the signal, they manage to have ultra-fast amps that don't expend all their energy on amplifying HF signals and blow up as a result. Apparently, Spectral amps really do blow up if not used with the 'correct' preamps and cables. Now... Arc Prediction actually creates ultra-high-frequency signals/noise. The NOS1 will pass these on perfectly to the power amp (if no preamp/vol-pot is used, as recommended by its Maker). Wouldn't this be a really bad idea with an ultra-high-bandwidth power amp??? Thoughts please... Mani. Title: Re: Arc Prediction & high-bandwidth amp - a disaster waiting to happen? Post by: PeterSt on August 25, 2011, 11:11:52 pm Any other simple questions ?
This ultra whatever high frequency energy is already 40dB down towards 96KHz. More can't be seen/measured. I would be bothered more about 96KHz "HiRes" which is 3dB down in that regions ... If they advise those cables, well, take them. But I wouldn't be so sure it works out for the better. Hard to tell ... Peter Title: Re: Arc Prediction & high-bandwidth amp - a disaster waiting to happen? Post by: BertD on August 26, 2011, 09:57:22 am Some of the highest bandwidth amps around are from Spectral. Now, Spectral are totally adamant that you need to use a Spectral preamp and Spectral/MIT interconnects with their power amps. The warranty is void if you do not do this. In other words the amp is not stable where the least thingy at the input makes it fry itself? So filters are needed to protect the amp so why not put it inside the amp (as most manufacturers do) giving people free choice to use anything they want around it? Do these amps have a CE certficate? :unsure: I am not a technical expert but isn't filtering (no matter where applied) always reducing the Slew Rate seen at the speaker terminals? Bert Title: Re: Arc Prediction & high-bandwidth amp - a disaster waiting to happen? Post by: manisandher on August 26, 2011, 10:26:38 am Hey Bert, I don't really know. Maybe there's a lot more to all this than meets the eye. In case you didn't know, the chief designer at Spectral is Keith Johnson, who is very well respected... oh and happened to be one of the designers of my PM2 ADC/DAC.
Mani. Title: Re: Arc Prediction & high-bandwidth amp - a disaster waiting to happen? Post by: BertD on August 26, 2011, 01:49:22 pm Hey Bert, I don't really know. Maybe there's a lot more to all this than meets the eye. Probably but still, if only a few cables different than their own can make the amp fry then there is seriously something wrong with the basic design of the amplifier. Filters as used in those MIT or their own interconnects should then be used inside the amplifier if you ask me... But perhaps then technical figures look a lot worse to impress? I do not want to be negative but do correct me if I am wrong... Bert |