Discussion of AC mains isolation transformers

[Speed Racer]

a) Build or use a power strip that has nothing but high-quality outlets and heavy gauge copper wire between them. Plugging ALL your components (or at least those that are contributing to any particular leakage loop) directly into this strip. This reduces the impedance between the components, thus reducing the effect of their leakage currents;

Alex (or any one else),

 

Do you know where I can buy a power strip like what your describe?

 

Thanks!

[Speed Racer]

I like the Tripp Lite aluminum housing ones with just a switch and breaker. These are the PS series, there are many versions to choose from such as the PS3612.

These work well, are inexpensive and readily available.

John S.

 

Thanks, John!

 

I think I will buy the Tripp Lite PS2408RA or PS3612RA. These have right angle receptacles which make life easier with wall warts. I don't think I will need more 8 plugs so I am leaning toward the PS2408RA.

[Speed Racer]

Alex,

 

If I have your ISO Regen (powered by an LPS-1) between my MacBook and my DAC, I don't want to put the computer or ISO Regen on the same power strip as the DAC, preamp, amps, etc., correct? Do I want them on a different circuit too?

 

Thanks!

[Speed Racer]

Alex or John,

 

Comments?

 

Alex,

If I have your ISO Regen (powered by an LPS-1) between my MacBook and my DAC, I don't want to put the computer or ISO Regen on the same power strip as the DAC, preamp, amps, etc., correct? Do I want them on a different circuit too?

Thanks!

[Speed Racer]

When I built my studio I went all Decora-style, and after researching the heck out of outlets (a bit before the total audiophile private-labeling and custom craze), in the end I went with Leviton's version of the hospital IG, the 16362-IGW.

They are available at Amazon for about half the price of the Hubbell: https://www.amazon.com/Leviton-16362-IGW-125-Volt-Receptacle-Straight/dp/B003ATKI78]

Alex and John,

 

Okay. I bought some of these receptacles and the Tripp Lite power strip. Do you have an opinion on power cables? Is the manufacturer supplied cable good enough or should I be looking for something more appropriate? I know that the stock power cables leak RFI and I know you can buy cables that have shielding to prevent that.

 

I am not trying to start a debate on cable quality. I am just trying to get an opinion.

 

Thanks!

[Speed Racer]

I bought a 1.8KVA Topaz 91018-11 Line Noise Suppressing Utra-Isolator (.005pF) transformer and received it today. I plugged it in to a wall outlet and then plugged a TrippLite power strip with all my audio equipment (not the computer) into it.

 

The first bit of good news is that the transformer is virtually silent. If I stick my head right next to it I can here a slight hum but it is well below the ambient noise of the room with no music playing. I have no idea how clean or dirty my AC power is on the outlet I had the audio equipment plugged into. I can say that I think the noise floor is lower. In other words, the background sounds quieter. It's like the music is coming from a noiseless place. The details and clarity in the timbre of voices and instruments has improved. Finally, the separation of instruments and voices is even better than before.

 

Listening to Steely Dan's "Hey Nineteen" is amazing. The soundstage is fantastic. It is not too wide and the I can clearly discern the location of the various instruments better than before. Wow. I just listened to CCR's "Susie Q". Wow...just wow!! The clarity, separation, and detail are incredible!

 

Using the Topaz transformer and TrippLite power strip is certainly a step up in sound quality. I am impressed! Now I just need to get the ISO Regen to complete the setup and I should be done.

[Speed Racer]

29 minutes ago, Jud said:

 

Proud purchaser of a Topaz 91002-32 a few days ago that's on its way to the electrical sub on our new home, so your story is, shall we say, music to my ears.

 

I think you are going to be very very happy. The Topaz/TrippLite power strip setup has made the single most significant change in sound quality I have experienced. I suspect my AC power situation was not very good.

 

I kind of wish I bought a 2.5KVA unit like you did now.

[Speed Racer]

3 minutes ago, One and a half said:

 

Which TrippLite power strip is installed? There are many to choose from nowadays. If you want further improvement, then by all means use a plain jane powerstrip (without suppression devices), if already done, then this post is of benefit to others.

 

I am using a TrippLite PS2408RA. This is the type John Swenson recommended.

[Speed Racer]

All I have to say is:

 

Thank you, John Swenson!!!

 

 

 

[Speed Racer]

leowood,

 

I am not really sure what all that means. All I know is using the Topaz isolation transformer with a standard TrippLite power strip has clearly improved the sound quality I get from my audio setup. 

[Speed Racer]

I bought a "Kill A Watt" to see how much power I am using through my 1.8kVA Topaz Ultra-Iso Transformer.

 

Between my Yggdrasil, Mjolnir 2, and Swan powered monitors, I am using 95VA. That's a bit more than 5% of the capacity of the transformer. The power factor is .88. I wonder how many VA the Schiit Vidar amps will use at normal listening levels. 

[Speed Racer]

I hope my Topaz is wired correctly.

 

It is wire this way:

 

Input side:

 

Black: Hot

White: Neutral

Green: GND

 

Jumpers:

 

H1 & H3

H2 & H4

 

Black wire on lower H1 terminal

White wire on lower H4 terminal

Green wire on lower GND terminal

Green wire on upper GND terminal goes to Topaz chassis

 

Output side:

 

Black: Hot

White: Neutral

Green: GND

 

Jumpers:

 

X1 & X3

X2 & X4

 

Black wire on upper X1 terminal

White wire on Upper X4 terminal

Green wire on Upper GND terminal

Green wire on lower GND terminal goes to Topaz chassis

 

It's wire the way the cover plate on the input says it should be wired for 120v in and 120v out. It says nothing about how to wire the ground.

[Speed Racer]

I think balanced power was discussed earlier but I don't think I understood it. Is there an advantage to that for audio? I read somewhere that I could wire my Topaz transformer for balanced power. Here is what I found for that:

 

After much internet searching, and thanks to the links above, here is how I've wired the transformer:

The primary and secondary are both in series.

Input:
Neutral (white) to H1
Hot (black) to H4
Ground to chassis

Output:
Hot 1 (white) to X1
Hot 2 (black) to X4
X2/X3 center tap connected to chassis ground and outlet ground.
 

I assume no jumpers are used. Is that the case?

 

Thoughts?

[Speed Racer]

Then I found this for doing balanced power:

 

=================================================

To be balanced mode, it should be wired as follows: 

 

INPUT: H1(HOT), H2H3(JUMPERED), H4(Neutral) (DO NOT tie any of the primary side wiring to chassis except the green safety ground wire!!) 

 

OUTPUT: X1(HOT), X2X3(JUMPERED and TIE just these 2 to chassis), X4(Neutral) (DO NOT tie either X1 or X4 to chassis) 

 

S1 (shield), S2 (shield) and both input and output safety grounds should be tied to chassis as well.

=================================================

 

I have no idea if this is correct or if there is any advantage to this.......

[Speed Racer]

I just picked up a Topaz Ultra-Isolator 91002-3 which is a .0005pF 2.5kVA transformer for cheap! I also have a 1.8kVA   .005pF model. I should have purchased the 2.5kVA model the first time around but I will keep both.

[Speed Racer]

The Topaz will buzz when there is DC offset in the AC mains. In other words, when it is doing its job. I would guess you have a dimmer switch or some other new device(s) being used that is causing this.

[Speed Racer]

I am not a big fan of uber expensive power line conditioners. The 2.5kVa Topaz 91002-31 isolation transformer that I am using right now was inexpensive and works fabulously! I think I paid $150 including shipping for it.

 

Read this thread from the beginning....

[Speed Racer]

No, the DC won't pass through the Topaz isolation transformer. Unless, of course, the Topaz is making a lot of noise because of the excessive DC. The DC blockers use big honking capacitors which don't pass DC either. But, make sure the DC blocker has as high an AMP rating as the Topaz.

[Speed Racer]

DC blockers and transformers do not pass DC offset, but they block it in different ways. DC blockers typically use big capacitors that don't pass DC offset. I don't know the physics behind it nor do I really care to know. AC transformers don't pass DC offset either. Again, I don't know the physics behind it nor do I really care to know.

 

I am sure you can find out all you want about this using Google.

[Speed Racer]

I am glad I have a Topaz isolation transformer and no DC blocker!!

[Speed Racer]

22 minutes ago, Abtr said:

The Topaz only has unbalanced output..

 

It is simple wire the 91002-31T, or any of the 120v/240v Topaz units, for balanced power. I get the 146dB CMNR plus the benefit of CMNR provided by the balanced configuration. I have read that is worth an addition 20dB of CMNR.

 

As I wrote previously, the Topaz runs cooler and quieter when configured to provide balanced power.

[Speed Racer]

It only takes about 10 minutes to make the wiring change. Easy enough to test....

[Speed Racer]

1 hour ago, mikicasellas said:

 

 

I just purchased a Topaz 91002-32 Line Noise suppressing Ultra-Isolator for $200, USED - GOOD CONDITION, but i looked and looked and looked until  i found some other places where they got theses gems by one unit or so, this unit sells for $1,250 in http://www.surplussales.com/item/_tp/91002-32d.html,

 

 

So you can find a really good unit for much less

 

That is about what I paid from my 91002-32. You got a very good deal on a nice unit!

[Speed Racer]

26 minutes ago, spacexpert said:

Could anyone please advise whether or not I have a dud IT?

 

I recently purchased a TOPAZ 91097-31.

 

I sent it to an electrician and they attempted to wire it for 220V input / output,  but admitted to being unfamiliar with the device.

The input side tested fine, but there was nothing on any of the output terminals X1 X2 X3 X4.

 

Looking inside I can see no jumpers installed on either the input or output side.

 

Does it sound like the missing jumpers is all I need to remedy?  Or should there be power on the output side regardless?

 

Thanks.   

 

According to my transformer's wiring diagram cover for 220V input and output, H2 and H3 are jumped together as are X2 and X3. Input terminals are H1 and H4 while output terminals are X1 and X4.

 

An electrician unfamiliar with the device should not touch the device UNTIL he becomes familiar with it...and not familiar by guessing!

[Speed Racer]

17 minutes ago, spacexpert said:

 

Cheers Speed Racer.   I have taken it to two electricians, and both tentatively poked and prodded at it like it was an electron bomb and then didn't seem to want anything to do with it.

 

Regardless I am hoping the missing jumper links are the reason it won't come to life on the output side. 

 

I guess I'll make some jumpers (cracks knuckles)  This should all go swimmingly.    

 

 

Both my -31 Topaz units came with 4 of these jumpers: