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Isolation transformers - where do I start?

Trying to get into power isolation. This idea seems to have merit because there seems to be less irritating high frequency distortion late at night than in the daytime.
So where do I start?
1)1 big 2kVa isolation transformer? Plug everything into it?

2) PS Audio "ultimate outlet". Plug everything into it?Reduces common mode noise by 40dB.

3) Sola constant voltage transformer 60 VA for the CDP and preamp (which draw 30 va each- I play music very soft - 1/2 watt output on the power amp - so probably much less than that).
- "Highly regulated sine wave outputs with harmonic distortion less than 3%"
- "Output voltage regulated +/- 1% with input voltage fluctuations of +10%/-20%."

4) Power conditioning shielded C-V transformer 140VA for CDP and PRE:
- reduces common mode noise by -120 dB / Normal mode noise -60 dB / <2pf capacitance between input and output wiring.
- Output regulation +/-3% with inout fluctuations +10%/-20%.

5) Get 2kVA for system and also smaller 60 VA for CDP only.

Is a power conditioning transformer ($250 for .14 kVA)better than just an isolation model ($250 for 2 kVA). I realize small capacity so only for CDP or preamp.

Any suggestions would be appreciated.
cdc

Showing 3 responses by cdc

cdc OP
1,929 posts
 
Thanks for the replies. The Equipower is impressive but their T1000 is $989 and the 1.5Q (15 amp) is $2,189. I would like to start cheaper as $1,000+ is beyond my budget.

Hopefully the basic ISO transformer gets pretty close. I will have to check on the weights and type of core before I buy.

I'm still not sure whether I should go with a big ISO transformer for my entire system ($250 for 2kVA) or a .14 kVA power conditioning "constant-voltage-transformer" for just the source and/or preamp. Maybe I'll just buy both and return what does not work as well.

Thanks Sean for the in depth reply and warning about the Sola.
cdc OP
1,929 posts
 
Thanks Buckingham, I will look into the Hubbel. I couldn't find Virtual Dynamics Company or Hubbel searching here at Audiogon. Do you have a link?
cdc OP
1,929 posts
 
Doing more research, not all isolation transformers are the same.
1) "Multi-shielded IT with interwinding capacitance .005 pF max and common mode noise attentuation 126dB. 120 volt / 4.17 amp. $360.00"
2) "Low leakage (hospital type): leakage current primary to secondary rated less than 50 micro-amps and is measured at less than 10 micro-amps. Power: 250 VA $133.00"
3) "Isolation transformer with static shield 150 VA $36.80."
4) "VA 150 capacity / 7.0 pounds / $45.34. The case and core and electrostatic shield are internally connected to a third conductor of NEMA standard cord and receptacle for safety"

So far #1 and #2 hospital grade looks best. Any thoughts?
I checked on ebay but not really sure what I would be getting / not returnable / get what you pay for / etc.
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