Discussion of AC mains isolation transformers

[Superdad]

1 hour ago, mikicasellas said:

I have contact with Walter Liederman from Underwood Hifi, I read only good things about this Equi=Core 1800 balanced power transformer.

 

Well here is a pic of the inside of that model:

 

Might be nice to know more about who winds their transformers and the specifications of it.

[One and a half]

2 hours ago, mikicasellas said:

 

 

I have contact with Walter Liederman from Underwood Hifi, I read only good things about this Equi=Core 1800 balanced power transformer.

 

So, is there any risk to do business with this brand ?

 

Thanks 

 

I would read post #1623 first.

[One and a half]

8 hours ago, Superdad said:

 

Well here is a pic of the inside of that model:

 

Might be nice to know more about who winds their transformers and the specifications of it.

Could be any number, the transformer in my Equi-Tech is made by Electronetics out Everett WA.

[Superdad]

9 hours ago, One and a half said:

Could be any number, the transformer in my Equi-Tech is made by Electronetics out Everett WA.

 

Pretty sad how they just run the secondary of the trans into the outlet on the right and then daisy-chain the rest of the outlets--using rather rather thin wire (looks like 18AWG/300V).  

And except for the ground screws they use the push-in holes for ALL the wires!  Here's the pathetic contact area of back-wire stab-in terminal (this from an industrial-grade outlet:

 

Yuck!

[Ralf11]

We need a whole thread to rant on stab-in terminals...

[mikicasellas]

On 4/26/2019 at 5:18 PM, ray-dude said:

Have you tried tightening the bolts on the unit?  I've been reminded a couple times recently that the mechanical nature of the transformers is a big part of buzzing

 

Ray-Dude:

 

I took my Topaz for service, they checked it, clean it and tighten the bolts, it really does not make any HUUM and the noise dropped

 

Thanks for the advice !!

 

Regards

[Ralf11]

where did you get your Topaz serviced?

[elpampeano]

I can get a Topaz 2.5 kv for a mere 75 dollars ! I make my own power strip with 4mm cable inside, and from the transformer, 4 x 2.5mm in starquad with outer ground wire. The sound ? Incredible, a giant foward step on transparency and 3d image.

[Bdht]

Will there still be leakage loops with this cable?

https://www.amazon.com/ATZEBE-Fiber-Optic-Optical-Supports/dp/B07KG7C25W/ref=mp_s_a_1_4?keywords=fiber+hdmi&qid=1558897583&s=gateway&sr=8-4

 

With this one that injects power at the output there wouldnt be, correct?

https://www.amazon.com/Kanex-Pro-Active-Optical-Cable/dp/B071YQDXS2?th=1&psc=1

[Bdht]

Im planning on adding Topaz ultra isolators to my AVR and projector, and as well breaking leakage loops via HDMI to ethernet convertors.

Current setup:
Outlet 1:
HTPC
AVR
Subwoofer 1
2 channel amplifier for 2 height channels

Outlet 2:
Projector
Subwoofer 2

The AVR, subwoofer 1, and 2ch amplifier on a 91001-42 topaz ultra isolator.

The projector on a 91095-32. Perhaps use a Jensen isomax isolator for subwoofer 2.

For the hdmi connections, I'm considering using the monoprice blackbird 4k hdbaset(or other 18gbps hdmi>ethernet device) when using an ethernet cable without the shield connected this should break leakage loops. I would also power the receiver and transmitter with an hdmi connection to the AVR with a linear power supply and connected to the topaz.

[Bdht]

Forgot to add my question

Trying to figure out what exactly to try for hdmi.  I cant find a full fiber cable, theyre all hybrids, fiber for the data and copper for 5v ground edid etc. 

 

So I was considering the hdmi to ethernet convertors.  They mention power over cable(POC) to power the receiver, although I believe it can be powered by its own supply as well.  Not sure if that will still have a leakage loop?

https://www.monoprice.com/product?p_id=30446&gclid=EAIaIQobChMI2ayg-Pa54gIVFo_ICh1dcgd2EAQYASABEgK97fD_BwE

 

Earlier its said that for ethernet the shield needs to be unconnected.  Do you have to make your own cables or is there one you can buy?

 

Anyone have any suggestions for breaking leakage loops over hdmi?  As I said in the previous post I want to have the AVR and projector on separate ultra isolators and the htpc not on one.

[One and a half]

19 hours ago, Bdht said:

Im planning on adding Topaz ultra isolators to my AVR and projector, and as well breaking leakage loops via HDMI to ethernet convertors.

Current setup:
Outlet 1:
HTPC
AVR
Subwoofer 1
2 channel amplifier for 2 height channels

Outlet 2:
Projector
Subwoofer 2

The AVR, subwoofer 1, and 2ch amplifier on a 91001-42 topaz ultra isolator.

The projector on a 91095-32. Perhaps use a Jensen isomax isolator for subwoofer 2.

For the hdmi connections, I'm considering using the monoprice blackbird 4k hdbaset(or other 18gbps hdmi>ethernet device) when using an ethernet cable without the shield connected this should break leakage loops. I would also power the receiver and transmitter with an hdmi connection to the AVR with a linear power supply and connected to the topaz.

 

Just a word of definition needed as a guide for your posts on isolation.

 

A Topaz Ultra isolator (transformer) tries really hard to block leakage currents. The lower the pf between the windings, the greater the impedance for these frequencies, but it is not a true isolation device as far as noise is concerned. True isolation is a light fibre for example, but not going to work for mains power.

 

What the Topaz will do, is to stop nasty voltage transients and severely cripple common mode noise from entering the clean area.

 

You're on the right track with the HDMI fibre cables and isolating signals from equipment with that method or similar. All AC devices should be plugged into the one Topaz/power strip at the one place. Once there are other transformers for individual equipment, such as sources and power amps for example are on the network, the grounds tend to lift reference from one equipment to the other. Once that happens, you end up with an uncontrollable noise generator as the reference has shifted to another spot. 

 

Don't forget Jensen isolators on the Cable/FM/TV antenna infeed. 

[One and a half]

On 4/30/2019 at 5:22 AM, Superdad said:

 

Pretty sad how they just run the secondary of the trans into the outlet on the right and then daisy-chain the rest of the outlets--using rather rather thin wire (looks like 18AWG/300V).  

And except for the ground screws they use the push-in holes for ALL the wires!  Here's the pathetic contact area of back-wire stab-in terminal (this from an industrial-grade outlet:

 

Yuck!

Agreed about the push in on the outlets.

However Push in technology when applied correctly works very well as described in this Phoenix video. 

[Bdht]

1 hour ago, One and a half said:

 

Just a word of definition needed as a guide for your posts on isolation.

 

A Topaz Ultra isolator (transformer) tries really hard to block leakage currents. The lower the pf between the windings, the greater the impedance for these frequencies, but it is not a true isolation device as far as noise is concerned. True isolation is a light fibre for example, but not going to work for mains power.

 

What the Topaz will do, is to stop nasty voltage transients and severely cripple common mode noise from entering the clean area.

 

You're on the right track with the HDMI fibre cables and isolating signals from equipment with that method or similar. All AC devices should be plugged into the one Topaz/power strip at the one place. Once there are other transformers for individual equipment, such as sources and power amps for example are on the network, the grounds tend to lift reference from one equipment to the other. Once that happens, you end up with an uncontrollable noise generator as the reference has shifted to another spot. 

 

Don't forget Jensen isolators on the Cable/FM/TV antenna infeed. 

Yup, I know the topaz is for the cmrr/tmrr, and I was under the impression that the leakage loops were broken with galvanic isolation on the signal cables like optical, usb high speed, or ethernet for digital, with jensen isomax transformers for analog signals, or with a power supply like the ultracap lps. And that when using the topaz needed to have all electrically connected equipment on the topaz. If something was off the topaz, without galvanic isolation on the signal cables, there would be a very high impedance connection/loop, increasing noise from leakage currents.

If I turn off an iso regens isolation, with a dac/headamp on a topaz and an htpc not, noise increases substantially, with the iso regens isolation, however, and using the topaz results in a perfectly clean signal. With the iso regens isolation, I wonder if the benefit I'm hearing is due to the full isolation, ground especially, or just the data lines. Due to the noticeable effect of the iso regens isolation I'd really like to try that over hdmi.

"Once there are other transformers for individual equipment, such as sources and power amps for example are on the network, the grounds tend to lift reference from one equipment to the other. Once that happens, you end up with an uncontrollable noise generator as the reference has shifted to another spot."

Could the iso regens isolation be tied to this when using a topaz?

I can't have the projector on the same topaz as the AVR, however, and I want the HTPC isolated from both units just like with the pc and the dac/headamp using the iso regen, and want the cmrr of the topaz for both the avr and projector.

With the hdmi>ethernet devices, everything I'm seeing has power over ethernet, where dc power is added after the ethernet transformers, this would create a leakage loop, correct? Maybe you can disable the power over ethernet feature by breaking traces

I can probably connect the htpc to the projector over hdmi, and the htpc to the avr with displayport to hdmi, instead of using the AVRs video pass-through. 

 

For the jensen iso max, one of the subwoofers cant be on the avrs topaz so I thought about using one to isolate that, but i dont have cable or an antenna though.

The AVR also doesn't have a grounded chassis, it has a 2 prong iec inlet, I don't know if that's something to consider. I still have the transformers wired with the floating secondary. When I originally wired my first topaz I brought it to a friend who's an electrician and he said everything checked out so that way it stayed and it sounds perfect, ultra clean and ultra detailed. So if it's safe and it sounds great I'm hesitant to change anything, your advise is definitely taken into account though.

[jamesg11]

Re tv aerial etc, which Jensen product?

[One and a half]

40 minutes ago, jamesg11 said:

Re tv aerial etc, which Jensen product?

This one, they work, I have two of them for each radio, installed since, woah, 2006. Cured ground loop hum.

 

 

[One and a half]

5 hours ago, Bdht said:

Yup, I know the topaz is for the cmrr/tmrr, and I was under the impression that the leakage loops were broken with galvanic isolation on the signal cables like optical, usb high speed, or ethernet for digital, with jensen isomax transformers for analog signals, or with a power supply like the ultracap lps. And that when using the topaz needed to have all electrically connected equipment on the topaz. If something was off the topaz, without galvanic isolation on the signal cables, there would be a very high impedance connection/loop, increasing noise from leakage currents.

If I turn off an iso regens isolation, with a dac/headamp on a topaz and an htpc not, noise increases substantially, with the iso regens isolation, however, and using the topaz results in a perfectly clean signal. With the iso regens isolation, I wonder if the benefit I'm hearing is due to the full isolation, ground especially, or just the data lines. Due to the noticeable effect of the iso regens isolation I'd really like to try that over hdmi.

"Once there are other transformers for individual equipment, such as sources and power amps for example are on the network, the grounds tend to lift reference from one equipment to the other. Once that happens, you end up with an uncontrollable noise generator as the reference has shifted to another spot."

Could the iso regens isolation be tied to this when using a topaz?

I can't have the projector on the same topaz as the AVR, however, and I want the HTPC isolated from both units just like with the pc and the dac/headamp using the iso regen, and want the cmrr of the topaz for both the avr and projector.

With the hdmi>ethernet devices, everything I'm seeing has power over ethernet, where dc power is added after the ethernet transformers, this would create a leakage loop, correct? Maybe you can disable the power over ethernet feature by breaking traces

I can probably connect the htpc to the projector over hdmi, and the htpc to the avr with displayport to hdmi, instead of using the AVRs video pass-through. 

 

For the jensen iso max, one of the subwoofers cant be on the avrs topaz so I thought about using one to isolate that, but i dont have cable or an antenna though.

The AVR also doesn't have a grounded chassis, it has a 2 prong iec inlet, I don't know if that's something to consider. I still have the transformers wired with the floating secondary. When I originally wired my first topaz I brought it to a friend who's an electrician and he said everything checked out so that way it stayed and it sounds perfect, ultra clean and ultra detailed. So if it's safe and it sounds great I'm hesitant to change anything, your advise is definitely taken into account though.

It's a little late to detail some responses, but don't float the output of the Topaz. Ground X4, it keeps the ground to neutral voltage at 0V. 

[One and a half]

On 5/24/2019 at 6:09 AM, elpampeano said:

I can get a Topaz 2.5 kv for a mere 75 dollars ! I make my own power strip with 4mm cable inside, and from the transformer, 4 x 2.5mm in starquad with outer ground wire. The sound ? Incredible, a giant foward step on transparency and 3d image.

Where, when did you receive the Accuphase cables? The 40th anniversary models.

[Bdht]

Found one!  18gbps, no power over cable.  It only supports 2.0 uncompressed audio, but I think Windows can upmix to Atmos now or Im sure I can find I way to encode the few 5.1 pcm tracks I have.

 

gofanco (TX&RX Kit, Part# HDBitT4K) https://www.amazon.com/dp/B07JNFVDNT/ref=cm_sw_r_cp_apa_i_tEz9Cb7V1KJME

 

Even with the secondary neutral grounded, the signal cable isolation is still important if say the htpc is not on a topaz and the avr is on a topaz.  The signal cable isolation will block traditional leakage but not high impedance leakage, although as far as I can tell the sound is great even if the latter is still there.  I've used an optical connection which would block the high impedance loop, but prefer the isolated usb connection, though that could be due to bandwidth limitations of optical.

[JohnSwenson]

On important detail for this discussion, a Topaz does NOT block leakage current! Leakage current is primarily line frequency ie 60HZ. The primary purpose of the transformer is to PASS 60Hz. Since AC power is 60Hz, if it blocked 60Hz it would be useless as a power delivery device. Thus leakage current sails right through a Topaz. The Topaz blocks high frequency signals, but since leakage current is 60Hz, that doesn't help.

 

So don't expect a Topaz to block leakage current. It is a great device for cleaning up high frequency noise on the AC line, but doesn't do anything for leakage.

 

John S.

[Bdht]

@JohnSwenson For the ethernet cables, do you disconnect the shield at both ends or just one?  Thanks!

[Bdht]

Found it! 18gbps, 7.1 pcm, no power over ethernet.  I think it says dc5v 4w consumption, so maybe I can use ultracap lps' on the two with an hdmi connection to the AVR?

https://www.troxellsolutions.com/products/av-essentials/interactive-presentation-devices/atlona-at-uhd-ex-70-2ps.html

 

[Bdht]

correction to that last post, its this unit instead for 2160p 60hz 4:4:4 8-bit or 4:2:0 10-bit hdr

https://atlona.com/product/at-hdr-ex-70-2ps/

 

the transmitter needs 5v 4w, the receiver needs 5v 6w, so would have to power the transmitter with the ground shunted ultracap lps.

[Bdht]

One more in case anyones interested.

Fiber instead of ethernet

 

https://www.monoprice.com/product?p_id=24279&gclid=EAIaIQobChMI8rX04_vR4gIV14WzCh1ltA3IEAQYASABEgI_LPD_BwE

 

https://www.amazon.com/dp/B073QLRJDR/ref=cm_sw_r_cp_apa_i_.T49Cb60CEPCY

 

Maybe these should be moved to a different thread, sorry if it got off topic.

[Ralf11]

https://audiophilestyle.com/forums/topic/56464-ac-line-noise/?tab=comments#comment-961748