Properly connecting an isotaion transformer

Vman: You can do exactly as you stated and achieve good results. The key here is how good the isolation transformers actually isolate their output from the line and whether or not the transformers & dedicated line are up to passing enough current without signal degradation.

For best results, isolation transformers should have a noise reduction of -120 dB's, very low capacitance and never be asked to deliver more than 60% ( 75% at max ) of their rated output. This would mean that a 2500 watt ( 2.5 KVA ) transformer should be run below 1500 watts of steady state draw with peaks held to below 1875 watts ( slightly over 15 amps ). These figures incorporates a "fudge factor" in terms of headroom if manufacturers are being a little "liberal" with the power ratings of these transformers. Otherwise, running an isolation transformer at or near rated capacity will actually introduce non-linear distortions into the system, defeating the purpose all-together. Sean
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Vman: Run 20 amp circuits all the way around rather than two 15's and the one 20 amp. The cost difference is next to nothing and the difference in potential performance due to lower source impedances with future upgradability ( current draw ) make it worthwhile.

As far as running two more lines, you may only need one additional line but two more transformers. That is, IF the current draw on all of the devices combined for that secondary line are less than 15 amps or so. If you need more current than this, use the two lines as you first suggested.

As i mentioned, there's nothing wrong with running one line for digital and analogue. That is, so long as they are thoroughly isolated from each other. If you're using the transformers that i think that you are, you're good to go. Sean
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I don't know what you have for speakers, listening room or listening levels, but i wouldn't run an amp that size with anything smaller than a 20 amp line and a 2.5 KVA transformer. I would really prefer to see an even larger transformer for this amp, but 2.5 KVA will work for most people with "reasonable" speakers and listening habits.

The reason that i say this is that at low impedances with insensitive speakers, this amp can pull GOBS of current with big peaks or when standing on the throttle. As a side note, this amp benefits quite noticeably from clean power, moreso than some other designs. Adding additional filter capacitance into the power supply also helps with bass impact and to further lower the noise floor. If you're not running this amp in balanced ( XLR ) mode, i would highly suggest checking into it. This amp, along with all other Sunfire products, does not use "standard" XLR pin configurations though, so verify compatability with your Pre/Pro before going that route.

As far as placing the transformers, the greater the distance from each other and the equipment, the better. Given that the field that they generate is directly related to the amount of current being passed, the one to worry about the most would be the transformer feeding the amp. Magnetic fields decay as a square, so moving the transformer twice as far apart results in four times the reduction in magnetic field strength. Having said that, i would keep them FAR away from any type of cabling if possible, as some cables make for excellent "antennas" to feed noise into the system. Sean
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Vman: If you would like and since you can't use them right away, send me your cabling and i'll burn in it for a week or so and ship it back to you. This should give you a better idea of what to expect from your system right off the bat. One catch here. You'll have to cover the shipping both ways : )

As to the transformer situation, i don't see a problem with using it to feed the whole system. You will probably end up drawing but a watt or two from each amplifier channel during normal use due to the high sensitivity of your speakers, so current draw is not a problem.

Outside of the iso transformer, what you might want to do is to use some type of device that offers further isolation between components and acts as a "power strip". This will allow you to divide the power coming out of the iso transformer in a somewhat orderly way and keep the components from "polluting" each other's AC supply AFTER the iso. Given that every device that you'll be using has some type of "switching" power supply in it, cleaning it up from the lines coming in and then isolating them from each other should yield further improvements.

I won't go into specifics in terms of brands to recommend, but some type of device that offers multiple feeds with each feed being seperate from the others AND having some type of filtering / surge suppression should do the trick. You can experiment with plugging the amp directly into the feed from the iso or through the "filtered power strip" to see what you think is best. If you don't notice a difference, you might be better off leaving it run through the "strip" for added surge protection.

As far as your installation goes, you'll probably have to angle your center channel speaker down somewhat. You might also want to think about placing some type of wide bandwidth absorption device on the ceiling near the speaker. This will minimize reflections and improve focus / imaging. I'm sure that you'll be very happy once everything is in place. I'm sure that you can't wait : ) Sean
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