Toroidal quality comparison? - diyAudio
Go Back   Home > Forums > Amplifiers > Power Supplies

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 21st October 2005, 09:47 AM   #1
diyAudio Member
 
Join Date: Apr 2005
Location: HK
Default Toroidal quality comparison?

I planned to build a PSU for my new diy dac, and now come to decision of choosing the toroidal transformer. I planned to use 50VA with 2 x 0-15V output. And fortunately I can get access to many various brand of toroidal in my local shops Now I had following listing (all are 50VA, 2 x0-15V):


Hammond 182K15 US$52 http://www.hammondmfg.com/182.htm
Multicomp TA050/15 US$18
Multicomp TI-027335 (encapsulated) US$21
Airlink (no model num) US$?
Clairtronic 12023 US$21.15 http://www.clairtronic.com/toroidal.htm
Nuvotem 0050P1-2-xxxK (encapsulated) US$21 http://www.nuvotem.com/en/products/std_encap230v.shtml


I had searched for many place in Internet and seems cannot found a comparison of any combinations of about. I would like to ask if anyone had experience with these stuff? Which one is better regardless of price?

Tha Hammond is comparitive expensive(well, may be this is just mark-up in my local shop) Is that it had some superior performance?
  Reply With Quote
Old 21st October 2005, 06:18 PM   #2
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Hi,
which ones include an electrostatic screen between the primary and secondary in the price? Do they all have dual 110V and/or 115/120v primary tappings. Are they suitable for just 60Hz or dual 60Hz/50Hz? Are any available with a Goss band to reduce hum field?
Then you might understand some of the cost difference. If all are identical then I would go cheapest.

By the way, I have an old Conrad Johnson PRE and it runs the regulator VERY hard from a much higher supply voltage than I expected. I don't know why. It also has NO electrolytics in the power supply nor anywhere else! Film and styrene caps throughout.
__________________
regards Andrew T.
  Reply With Quote
Old 24th October 2005, 06:26 AM   #3
diyAudio Member
 
Join Date: Apr 2005
Location: HK
Thanks Andrew, I had not paid notice on spec parameters other than primary & sec.

But other than spec, any one had try AB sound quality comparison with differnet brand toroidal? I understand that is is very cost non-effective, but curious if anyone can share some experience on this.

BTW, I forgot to share mine experience at first I had build a headphone amp, and had tried 3 transformers:

- At first, I use a traditional EI transformer for PSU (the PSU is in seperate case). While providing more dynamic and power to the sound, its very noisy and detail is not good.
- Second, I borrow a unbrand toroidal from my friend. Its much more clean, clear and is no noise, detail is better, but the sound come out seems like limited somewhere. All things cannot extend enough, and not dynamic enough.
- At last, I bought a Nuvotem 0050P1-2-xxxK (encapsulated model). Well, shortcoming of the above 2 disappeared, and contain all goodies of previous 2, and even better

So, this is why I ask if anyone had comparison with those branded toroidal. I DO believe that branded one should perform better.

Thanks for any advise!
  Reply With Quote
Old 24th October 2005, 07:19 AM   #4
diyAudio Member
 
analog_sa's Avatar
 
Join Date: Aug 2002
Location: Sofia
Hi siuguyguy

Don't i also wish such info was available? There were several threads about power transformer design and some sensible opinions were expressed regarding the effects of flux density, dc saturation and power bandwidth. Sadly, all provided little correlation with subjective effects.

So, what's a safe way to choose a good sounding transformer? It is probably best to use one of the 'industry standards' like Avel Linberg, Plitron, Lundahl.
  Reply With Quote
Old 24th October 2005, 11:06 AM   #5
diyAudio Member
 
jan.didden's Avatar
 
Join Date: May 2002
Location: Great City of Turnhout, Belgium
Blog Entries: 7
If you use a transformer for a low-power load like a DAC, definitely do not take a toroid! Toroids are very wideband devices as transformers go and that means all the noise, junk, scratches etc on the mains are neatly transferred to the DAC supply. For low-power loads a classical E-I transformer, preferably with totally separate primary and secondary windings, are the very best for low noise and good low-level detail. The only reason we use toroids in power amps is their low price and relatevely small size for a given power rating, but that should not be important for small transformers.

Jan Didden
__________________
I won't make the tactical error to try to dislodge with rational arguments a conviction that is beyond reason - Daniel Dennett
Check out Linear Audio Vol 7!
  Reply With Quote
Old 24th October 2005, 11:25 AM   #6
diyAudio Member
 
Join Date: Feb 2005
Location: Southern France
Jan, that's interesting.

I know toroidal transformers are more efficient, but I also thought they radiated less EMI... is that wrong, or is there something I overlooked?

Ok and if toroids are not the way to go for low-power circuits, how about the new R-types?
  Reply With Quote
Old 24th October 2005, 12:44 PM   #7
diyAudio Member
 
analog_sa's Avatar
 
Join Date: Aug 2002
Location: Sofia
Quote:
thought they radiated less EMI
What exactly is EMI?

Toroids obviously tend to radiate less of everytnig and that's why they are the darlings of manufacturers - just perfect for really stuffed boxes. Radiation and wideband is not the same.


Anyway, this is theory and the original poster, siuguyguy, wanted to know how various brands sound. I have noticed, through experience, that generalisations don't work too well. Some toroids, even at low power levels can provide better sound than EI types. The wide bandwidth can be reduced with a suitable power cord.
  Reply With Quote
Old 24th October 2005, 02:09 PM   #8
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
I'm using this Hammond transformer (D229 type) in a DAC and I'm very happy with a performance. Proper filtering in subsequent stages provides better sounding supply than I was getting with batteries.

I mainly experimented with transformers in GC, and here I tried once EI type (250VA) and definitely the sound wasn't as good as with Plitron toroid ( it was sort of muffled and not very involving).

Then I tried cheap toroids from China (looking almost exactly like Plitron) and here the biggest defficiency was lack of bass and rythmical definition; although the transormers were half price of Plitrons, I couldn't use them.

It seems like single primary is better than dual.

My recent experiments indicate also that winding secondary first ( primary on the outside) produces better results: the sound is more direct and more natural, with less "haze" and grit.

I had some transformers were secondary was done with parallel runs of wire (to increase current capacity), but I didn't really like it, it seemed that I was loosing focus in the sound.

I recently started ordering toroids with amorphous core, and those are completely different ball game. The sound initially is somewhat bright, but the amount of detail and definition is greatly improved. Also, after breaking in the brightness dissapears.

Bigger wattage is not neccessarily better, while you gain on certain qualities, you might be loosing on others (more body and drive, less detail and immediacy) so it's best to balance it properly.

With GC, I usually go for 300VA toroids these days.
Attached Images
File Type: jpg tran.jpg (39.4 KB, 1252 views)
__________________
www.audiosector.com
“Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it.” - JC
  Reply With Quote
Old 24th October 2005, 03:16 PM   #9
diyAudio Member
 
Join Date: Feb 2005
Location: Southern France
Quote:
Originally posted by analog_sa

What exactly is EMI?
EMI = ElectroMagnetic Interference
  Reply With Quote
Old 24th October 2005, 03:44 PM   #10
diyAudio Member
 
analog_sa's Avatar
 
Join Date: Aug 2002
Location: Sofia
Quote:
EMI = ElectroMagnetic Interference
Ok, let me rephrase: What exactly is ElectroMagnetic Interference in the context of radiating transformers?




Peter

Invaluable information indeed. Many thanks for sharing. As no good deed should go unpunished i am anticipating someone to bust the myth of the amorphous core before long
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Quality Control differences = variations in sound quality? KT Class D 3 4th June 2014 12:02 AM
sound quality comparison anwaypasible Car Audio 6 3rd August 2007 03:43 AM
A noobs GC sound quality comparison markiemrboo Chip Amps 2 10th December 2006 12:23 PM
where to buy a high quality toroidal in the UK? greg filip Parts 17 1st June 2005 09:15 AM
Best Transformers (Encapsulated Toroidal or Open Frame Toroidal) Rixsta Pass Labs 10 23rd April 2004 03:41 AM


New To Site? Need Help?

All times are GMT. The time now is 02:52 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2