Anyone know of a US source for ESL toroids? - Page 3

CharlieM · 3rd October 2009, 09:38 AM

Followup: A week or so ago I emailed Antek asking if their 50VA 2x115V / 2x6V toroids used grain oriented cores and what the insulation values are between prim/prim & sec/sec windings but I've gotten no response so far. I suppose at $13 a piece they're cheap enough I wouldn't get burned too badly if I bought some to play with-- which I may do that at some point but for now I'm gonna keep looking for 230v/6v toroids with single windings; although I expect it will be hard to find a source that will ship to the US.
It's not like I'm desperate to find some-- just curious if changing from my current 100:1 EI core trannies to a tandem 68:1 toroid setup would improve my speakers' high frequency response. I like a lot of treble, since I'm a bit treble-deaf, and I'm having to add quite a bit of EQ boost above 5khz to get it where I like it.

Again-- If anyone out there finds some suitable cheap toroids available here in the US, please let me know. Thanks all!

Few · 3rd October 2009, 11:07 PM

I think you should try these instructions for winding your own and then let me know how it all turns out so I can learn from your experience

http://quadesl.com/pdf/trans_inst.pdf

Few

CharlieM · 4th October 2009, 02:03 AM

Geeze, I hope you're kidding.... thanks for the tip but your suggestion presumes that I would know what wire sizes to use and number of turns needed--- sadly I'm completely ignorant about all that stuff. Actually, I had thought winding my own but all the info I could find on it wasn't geared to ESL applications so I really wasn't able to learn anything. Old dogs don't learn new tricks easy anyway.

Few · 4th October 2009, 04:09 PM

The smiley face was meant to assure you I was kidding, but only because it was clear from the beginning of your thread that making a transformer from scratch wasn't what you were aiming for. I'm sure we could each figure out how to wind a transformer as Sheldon describes, but I don't currently have the expertise to make intelligent design choices any more than you do. Maybe someone else can chime in with a way to distill the design choices down to something newbies can work with. Until that happens, I'm with you in your quest for a source of relatively inexpensive toroids that'll get the job done.
Few

CharlieM · 5th October 2009, 09:03 AM

yeah, Few, good idea...

I'm sure we're not the only ones that would welcome someone posting a tutorial on winding trannies for ESL's!

Calvin · 5th October 2009, 09:21 AM

Hi,

have a look at Amplimo datasheets and the Patent of Mr. v.d.Veen
publ.-no.: 9300433, Int.-Claims: H01F 19/02, H01F 27/28, Date: 03,10th,1993
"Step Up Transformator" (in Dutch, maybe ther´s an english version too)

jauu
Calvin

rkellyfitz · 31st October 2009, 11:51 AM

Calvin,

Can I use a standard 50hz step-up transformer for a full-range ESL?

I am an American living here in Beijing right near the "Silicon Valley of China", which is an electronics market with a goldmine of every kind of component for cheap.

I was just there today looking at tons of giant El and toroid transformers, but when I told them I wanted to use it to step up a 20-20K hz audio signal they told me it wouldn't work because they were designed for 50hz. Is this right?

What specs should I look for in these transformers here to find some that will work for ESL's? These places can even custom-make them for me, but they seem very confused by the 20-20K hz issue and seem to only make standard 50hz transformers.

Thanks!

Calvin · 31st October 2009, 12:24 PM

Hi,

Q: Can I use a standard 50hz step-up transformer for a full-range ESL?
A: probabely not, but not because it is designed for 50Hz usage but because of a too low primary inductance and maybe wrong core material.

You need lots of primary inductance to reach down to 20Hz, more than normal power trannies have. For hybrid panels working >200Hz prim inductance is usually sufficient. The core should be wound from thin grain oriented material, not ferrite or similar. Then bandwidths >20kHz are possible.

jauu
Calvin

rkellyfitz · 31st October 2009, 09:34 PM

Calvin, thanks for your answer!

1) "too low primary inductance"--what value of primary inductance would I be looking for to reach down to 20 hz? What determines the primary inductance, and is it helped by having larger toroids, i.e. 100VA or more?

2) A core of "thin grain oriented material, not ferrite or similar"--what specific material should I ask for ideally?

The great thing about these markets here in Beijing is that I can have them custom-make almost anything I want. What are the idea specs I should ask for for ideal trannies for full-range ESL's?

Calvin · 1st November 2009, 09:00 AM

Hi

I repeat:
have a look at Amplimo datasheets and the Patent of Mr. v.d.Veen
publ.-no.: 9300433, Int.-Claims: H01F 19/02, H01F 27/28, Date: 03,10th,1993
"Step Up Transformator" (in Dutch, maybe ther´s an english version too)

jauu
Calvin

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3rd October 2009, 09:38 AM	#21
CharlieM diyAudio Member Join Date: Feb 2008 Location: Savannah, GA	Followup: A week or so ago I emailed Antek asking if their 50VA 2x115V / 2x6V toroids used grain oriented cores and what the insulation values are between prim/prim & sec/sec windings but I've gotten no response so far. I suppose at $13 a piece they're cheap enough I wouldn't get burned too badly if I bought some to play with-- which I may do that at some point but for now I'm gonna keep looking for 230v/6v toroids with single windings; although I expect it will be hard to find a source that will ship to the US. It's not like I'm desperate to find some-- just curious if changing from my current 100:1 EI core trannies to a tandem 68:1 toroid setup would improve my speakers' high frequency response. I like a lot of treble, since I'm a bit treble-deaf, and I'm having to add quite a bit of EQ boost above 5khz to get it where I like it. Again-- If anyone out there finds some suitable cheap toroids available here in the US, please let me know. Thanks all!

3rd October 2009, 11:07 PM	#22
Few diyAudio Member Join Date: Apr 2004 Location: Maine, USA	I think you should try these instructions for winding your own and then let me know how it all turns out so I can learn from your experience http://quadesl.com/pdf/trans_inst.pdf Few

4th October 2009, 02:03 AM	#23
CharlieM diyAudio Member Join Date: Feb 2008 Location: Savannah, GA	Geeze, I hope you're kidding.... thanks for the tip but your suggestion presumes that I would know what wire sizes to use and number of turns needed--- sadly I'm completely ignorant about all that stuff. Actually, I had thought winding my own but all the info I could find on it wasn't geared to ESL applications so I really wasn't able to learn anything. Old dogs don't learn new tricks easy anyway.

4th October 2009, 04:09 PM	#24
Few diyAudio Member Join Date: Apr 2004 Location: Maine, USA	The smiley face was meant to assure you I was kidding, but only because it was clear from the beginning of your thread that making a transformer from scratch wasn't what you were aiming for. I'm sure we could each figure out how to wind a transformer as Sheldon describes, but I don't currently have the expertise to make intelligent design choices any more than you do. Maybe someone else can chime in with a way to distill the design choices down to something newbies can work with. Until that happens, I'm with you in your quest for a source of relatively inexpensive toroids that'll get the job done. Few

5th October 2009, 09:03 AM	#25
CharlieM diyAudio Member Join Date: Feb 2008 Location: Savannah, GA	yeah, Few, good idea... I'm sure we're not the only ones that would welcome someone posting a tutorial on winding trannies for ESL's!

5th October 2009, 09:21 AM	#26
Calvin diyAudio Member Join Date: Nov 2004 Location: close to Basel	Hi, have a look at Amplimo datasheets and the Patent of Mr. v.d.Veen publ.-no.: 9300433, Int.-Claims: H01F 19/02, H01F 27/28, Date: 03,10th,1993 "Step Up Transformator" (in Dutch, maybe ther´s an english version too) jauu Calvin

31st October 2009, 11:51 AM	#27
rkellyfitz diyAudio Member Join Date: Oct 2009	Calvin, Can I use a standard 50hz step-up transformer for a full-range ESL? I am an American living here in Beijing right near the "Silicon Valley of China", which is an electronics market with a goldmine of every kind of component for cheap. I was just there today looking at tons of giant El and toroid transformers, but when I told them I wanted to use it to step up a 20-20K hz audio signal they told me it wouldn't work because they were designed for 50hz. Is this right? What specs should I look for in these transformers here to find some that will work for ESL's? These places can even custom-make them for me, but they seem very confused by the 20-20K hz issue and seem to only make standard 50hz transformers. Thanks!

31st October 2009, 12:24 PM	#28
Calvin diyAudio Member Join Date: Nov 2004 Location: close to Basel	Hi, Q: Can I use a standard 50hz step-up transformer for a full-range ESL? A: probabely not, but not because it is designed for 50Hz usage but because of a too low primary inductance and maybe wrong core material. You need lots of primary inductance to reach down to 20Hz, more than normal power trannies have. For hybrid panels working >200Hz prim inductance is usually sufficient. The core should be wound from thin grain oriented material, not ferrite or similar. Then bandwidths >20kHz are possible. jauu Calvin

31st October 2009, 09:34 PM	#29
rkellyfitz diyAudio Member Join Date: Oct 2009	Calvin, thanks for your answer! 1) "too low primary inductance"--what value of primary inductance would I be looking for to reach down to 20 hz? What determines the primary inductance, and is it helped by having larger toroids, i.e. 100VA or more? 2) A core of "thin grain oriented material, not ferrite or similar"--what specific material should I ask for ideally? The great thing about these markets here in Beijing is that I can have them custom-make almost anything I want. What are the idea specs I should ask for for ideal trannies for full-range ESL's?

1st November 2009, 09:00 AM	#30
Calvin diyAudio Member Join Date: Nov 2004 Location: close to Basel	Hi I repeat: have a look at Amplimo datasheets and the Patent of Mr. v.d.Veen publ.-no.: 9300433, Int.-Claims: H01F 19/02, H01F 27/28, Date: 03,10th,1993 "Step Up Transformator" (in Dutch, maybe ther´s an english version too) jauu Calvin