Anyone know of a US source for ESL toroids?

[CharlieM]

Update… good news and bad news:

The good news is that I found and purchased four 50VA 230v/2x6v Farnell toroids from their U.S. distributor, Newmark. They sound fantastic driving my speakers and my amps seem OK with them so my problem is solved.

The bad new is that Newmark has discontinued stocking those trannys for sale in the U.S. and after filling my order they had only two left. I don't need any myself but but I'm looking for some for a friend's ESL project.

A company in the U.K. called “Airlink” has 50VA 230v/2x6v trannys at a great price (9 pounds) and they sell retail at their website but when I attempted to place an order, their automated service would not complete the order without me first typing in the shipping cost. I then received an automated email from Airlink stating they would get back to me shortly with the shipping cost and I could then complete the order. It’s been almost two weeks without a response so my search continues…

[DavidJanszen]

Originally Posted by CharlieM

Update… good news and bad news:

. . . 50VA 230v/2x6v Farnell toroids . . . that Newmark has discontinued stocking

FWIW, the US distributor is Newark, where Farnell is Newark's parent company, which stocks Multipcomp's transformers and drop ships to Newark's US customers for a $20 handling fee.

It is the single primary/single secondary unit that you must have ordered and that will no longer be stocked. Multicomp's single primary/dual secondary line is available, although the 50VA 230V/6V-6V units are not in stock, and have a predicted lead time of 4 months. Still, if enough people pool their money and place a consolidated order, Newark may be able to persuade Multicomp to run a batch sooner than that.

[CharlieM]

Originally Posted by DavidJanszen

FWIW, the US distributor is Newark, where Farnell is Newark's parent company, which stocks Multipcomp's transformers and drop ships to Newark's US customers for a $20 handling fee.

It is the single primary/single secondary unit that you must have ordered and that will no longer be stocked. Multicomp's single primary/dual secondary line is available, although the 50VA 230V/6V-6V units are not in stock, and have a predicted lead time of 4 months. Still, if enough people pool their money and place a consolidated order, Newark may be able to persuade Multicomp to run a batch sooner than that.

I bought the ones shown in the links below. I sure hope you're right about those trannys possibly being available again in a few months because the price was great and I couldn't be happier with their sound in my hybrids.
If anyone wants to go in for a group buy, count me in for another quad!
MULTICOMP|MCFG050/06|TOROIDAL TRANSFORMER VOUT: 6V | Newark.com
The Jazzman's Electrostatic Loudspeaker Blog

[CharlieM]

Originally Posted by DavidJanszen

FWIW, the US distributor is Newark, where Farnell is Newark's parent company, which stocks Multipcomp's transformers and drop ships to Newark's US customers for a $20 handling fee.

It is the single primary/single secondary unit that you must have ordered and that will no longer be stocked. Multicomp's single primary/dual secondary line is available, although the 50VA 230V/6V-6V units are not in stock, and have a predicted lead time of 4 months. Still, if enough people pool their money and place a consolidated order, Newark may be able to persuade Multicomp to run a batch sooner than that.

I bought the ones shown in the links below. I sure hope you're right about those trannys possibly being available again in a few months because the price was great and I couldn't be happier with their sound in my hybrids.
If anyone wants to go in for a group buy, count me in for another quad!
MULTICOMP|MCFG050/06|TOROIDAL TRANSFORMER VOUT: 6V | Newark.com
The Jazzman's Electrostatic Loudspeaker Blog

[DavidJanszen]

Originally Posted by CharlieM

I bought the ones shown in the links below.

Okay, now go to that link, which is for the single primary/single secondary unit, which is no longer available. Now click on the [SHOW SUBSTITUTES] button at the bottom of the description. This will take you to the dual secondary version, which is the one that can be ordered.

It is not shown as being on back order, so when someone orders it, that is what will start the 85 day clock.

On the plus side, the minimum quantity is one, so a large quantity is not needed to start the clock. My point was that a large quantity might speed it up. It is also possible that the lead time is not accurate, and could be shorter if, for some other reason, a production run is made.

[CharlieM]

Hey David, that's great info.. thanks for that tip.
You know, I spent months designing and building my stats and I'll bet most others here spent at least a couple of months on their builds too.... so, it seems to me that waiting 85 days for trannys wouldn't be a big deal if the trannys are ordered at the start of a build.

[Few]

Originally Posted by CharlieM

I bought the ones shown in the links below. I sure hope you're right about those trannys possibly being available again in a few months because the price was great and I couldn't be happier with their sound in my hybrids.
[/url]

Hey CharlieM, thanks for all the updates. What configuration are you using your transformers in (series...parallel...voltage ratio...)? Glad to hear it's working out so well for you.
Few

[CharlieM]

Originally Posted by Few

Hey CharlieM, thanks for all the updates. What configuration are you using your transformers in (series...parallel...voltage ratio...)? Glad to hear it's working out so well for you.
Few

Hi Few,
Long time no see, buddy. These trannys have dual windings on the 6v side and a single winding on the 230v side. I followed one of Calvin's threads and wired them up up backwards in tandem, 6v windings wired parallel facing the amp and 230v windings wired series facing the stators. The 230v side is center tapped out to the neutral side of the bias power supply for the diaphragm. OK, for a single tranny the ratio would be (230/6)= 38:1 so a tandem would be 2x38= 76:1 Calvin's thread indicates that losses would make the actual step up in praxis around 68:1.

My stat panels are 12X48 inches with 1/16 stator/diaphram spacing, which should be around 1nf of capacitance (?). Please note that I've got a 1ohm 10 watt wire-wound resistor in the hot lead between the amp and trannys.

I'm biamping with active x-over @ 380 hz and (2) 225w/channel Carver amps. I don't know that anyone has tried these trannys in ESL's so I was worried about shorting one out and smoking an amp but I've cranked up the volume momentarily to way past my pain threshold and nothing smoked. I don't have any measuring equipment, only my ears, but it sounds wonderful to me.

I can't figure out how to upload a wiring sketch here but as soon as I've posted this message I will add a wiring sketch on my blog page here:
The Jazzman's Electrostatic Loudspeaker Blog

[chinsettawong]

CharlieM

I've tried a few off the shelve toroids with similar configuration that you have mentioned. However I found that the high frequencies from these trannys were dull. I didn't feel it at first, but when I compared the sound with my other speakers, it was very obvious. Don't you have that problem?

Wachara C.

[Few]

Originally Posted by CharlieM

Hi Few,
Long time no see, buddy.

Likewise. I'm still around--sometimes lurking, sometimes chiming in with posts. The tone of some of the "repartee" here in diyaudio-land often puts me off a bit so I periodically consider signing off for good, but I can't seem to kick the habit of reading about speaker design.

Thanks for the info on your transformer set-up. Have you considered taking the measurement plunge? It seems to get easier and easier with free software and such, and you might be able to squeeze the last ounce of performance from your creations. They look great, by the way.

The ESL panels are really great for jazz, aren't they? I'll never forget the first time I heard John Coltrane's Giant Steps through my diy-ESLs. It felt more like a time machine than an audio reproduction system. Even with the flaws in the recording it was really memorable.

Thanks again for sharing your progress.
Few