^same experience. Helpful, receptive and open. He had shared a photo of his listening room, certainly had the affliction. And engaged in the recording industry through his career. That was fascinating.
Open is not the adjective I would use. I found him set in his ways when I dealt with him. I asked for 10-15 W, 5 kΩ primary, 8 and 4 Ω secondaries, 100 mA for a 300B and he responded, "that's not what you want". He then wanted me to buy his much more expensive "special" 300B transformer design, preferably with silver windings. I had to push back to get what I wanted.
The transformer I received was supposed to handle 15 W down to 20 Hz but saturated below 40 Hz at 10 W. That didn't impress me much either.
I enjoy doing business with Toroidy in Poland. They make output transformers too.
Tom
The transformer I received was supposed to handle 15 W down to 20 Hz but saturated below 40 Hz at 10 W. That didn't impress me much either.
I enjoy doing business with Toroidy in Poland. They make output transformers too.
Tom
I found Jack to make a quality product, but very stubborn and intolerant to discussion that might challenge his ways.
Once had him make 4 power transformers with appropriate specifications that he accepted. Once we agreed on that, I asked him what the approximate DC resistance each winding was going to be, just so I could start modeling my power supply. He became dictatorial and irrational. Said, "I don't design transformers for target DCR, it's a meaningless parameter and &%G$#("
I responded very clearly that I wasn't asking for a target DCR for him to build to, I actually did not care what the values were from a pass/fail perspective. I merely wanted to know what he expected them to be based on his design. He knew, based on VA ratings and voltages, how many turns of what size wire around what size core he was going to wind. A ballpark length of wire is very easy for a transformer winder to approximate. But he adamantly refused to do so.
I don't think it was laziness on his part; I do believe he knew exactly how many turns of wire he was going to wind. I think he simply refused to put 3 minutes of effort to customer satisfaction; how dare I ask for information that was not important to him.
Sure, once the transformers arrived, I was able to take all my measurements, but I also lost many weeks in productivity in purchasing other power supply components until I knew exactly what I was getting.
That was my last time buying from him. Nearly all other suppliers will provide either DCR specifications or impedance/voltage regulation parameters so the end user will understand how the transformer will behave under load. Not Jack. You get what you get; a fine way to insulate yourself from performance responsibility.
Once had him make 4 power transformers with appropriate specifications that he accepted. Once we agreed on that, I asked him what the approximate DC resistance each winding was going to be, just so I could start modeling my power supply. He became dictatorial and irrational. Said, "I don't design transformers for target DCR, it's a meaningless parameter and &%G$#("
I responded very clearly that I wasn't asking for a target DCR for him to build to, I actually did not care what the values were from a pass/fail perspective. I merely wanted to know what he expected them to be based on his design. He knew, based on VA ratings and voltages, how many turns of what size wire around what size core he was going to wind. A ballpark length of wire is very easy for a transformer winder to approximate. But he adamantly refused to do so.
I don't think it was laziness on his part; I do believe he knew exactly how many turns of wire he was going to wind. I think he simply refused to put 3 minutes of effort to customer satisfaction; how dare I ask for information that was not important to him.
Sure, once the transformers arrived, I was able to take all my measurements, but I also lost many weeks in productivity in purchasing other power supply components until I knew exactly what I was getting.
That was my last time buying from him. Nearly all other suppliers will provide either DCR specifications or impedance/voltage regulation parameters so the end user will understand how the transformer will behave under load. Not Jack. You get what you get; a fine way to insulate yourself from performance responsibility.
"I don't design transformers for target DCR, it's a meaningless parameter and &%G$#(""
As I recall, there was something on his website warning NOT to ever ask this question. Hey we all have our pet peeves! Clearly this is one of his. My guess is a BAD interaction with an unruly customer when the DCR was 1 ohm different that quoted or something like that.
As I recall, there was something on his website warning NOT to ever ask this question. Hey we all have our pet peeves! Clearly this is one of his. My guess is a BAD interaction with an unruly customer when the DCR was 1 ohm different that quoted or something like that.
It is a shame audio transformer manufactures are going away. Magna Quest, Transcender, now Electra-Print. Two of the best audio transformers ever built are Dynaco ST-70 and ST-35 audio transformers. I visited an old site that tested about 40 vintage transformers and the Dynaco were best. Many were poor performers as viewed on the input and output wave forms. Dynaco ST-35 (Z-565) are 8K primary impedance and I believe ST-70 are 6K. 6K unloads tubes impedance such as 6L6GC tubes specified 4,5K plate to plate for superior distortion products at 6K primary impedance. Triode Electronics sells ST-70 audio transformer clones, but not the Z-565 at the moment. The Z-565 used to be for sale from Triode Electronics. Vintage Dynaco audio transformers are listed on eBay.
The ST-70 used the Dynaco A-470, which is 4.3K plate-to-plate.
Told me I was wasting my time choke loading a Sony VFET for a preamp. I wanted to order a pair of his chokes and was ready to pay. This was my first time with transistor choke loading and I bought a pair of cheap Hammonds instead. They actually worked quite well. So, he saved my hundreds of dollars and I still use Hammonds.
Jack made some excellent output transformers for my GM70 power amplifier and 71A headphone amp projects, no complaints. He definitely had strong opinions and was passionate about tube audio. I enjoyed my chats with him.
Well yeah - I concede that he knew his stuff, but, but I had to practically fight him to get the transformers made for my experimental headphone amp (which sadly didn't work so well due to compensation issues). I'm going to one of these days plunk those transformers on the bench and characterize them to see what I got for my money.
There are very few transformers made for vacuum tube headphone amp duty. Transcendar made one model that worked well for me - I have two pairs of them and one wound special with no gap for a parafeed headphone amp.
There are very few transformers made for vacuum tube headphone amp duty. Transcendar made one model that worked well for me - I have two pairs of them and one wound special with no gap for a parafeed headphone amp.
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I have a pair of Hashimoto single ended transformers that I will have to have to bust out and examine one of these days, with a project in mind. I also have a pair of Sophia Electric transformers that were made to work with an 845 - those are probably also decent quality.
And Monolith Magnetics (BE) which is in the Tamura/Tango league (will do custom designs)
Intact Audio (Dave Slagle) also top notch
Sowter (UK), Mastersound (Italy), Silk/SAC (Thailand), Iso/Tango (JP)
Mercury Magnetics, and Heyboer will do custom designs
For non tube specific applications there is also Cinemag.
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Back before the dawn of Tubelab Inc a coworker at Motorola named Albert Pagan decided to build a "Bugle 45" which was a popular build on the web around 2000, so he ordered a pair of custom EP OPT's, a choke and a power transformer. His build stalled due to a sick parent, and I was tinkering with a 45 based amp that would eventually become the Tubelab SE. I asked to borrow his OPT's which sounded much better than the OPT's that I had pulled out of some dead amps. I knew that I had to give the OPT's back to Albert, so I ordered a set of EP's for myself. After building my amp some friends expressed interest in copying my amp. I called Jack at EP and asked for info as to how others could get the same transformers that Albert and I had. Jack told me to ask for the Albert Pagan design. I even posted this info on my original web page in about 2005. A year or so later A fiend called to say that he was cussed out by the angry old man on the phone who said that he never heard of Tubelab and that he wished that I and Albert would die and take the web site with them. I immediately removed all references to EP from my web site and never mentioned them again.
I had heard several stories, and don't know which if any were true, but there may have been TWO Jack's, father and son. At least that would explain the two very different personalities, and the lack memories of previous conversations.
Shortly after that I saw an Ebay add for some surplus "300B OPT's" from a seller in California. I bought a pair, liked them and bought the remaining stock of about 30 transformers. This was from the first time that Transcendar shut down. I made some amps with them and sold a few at hamfests and to friends until I had only a few transformers left, while I still lived in Florida. Last week I was digging in my storage site and found an unopened box from my move to West Virginia 10 years ago. Surprise, I found 5 more Transcendar OPT's still in their sealed boxes.
I'm not sure the older Elliano was ever directly involved with Electra-Print, but I no longer remember all of the details, but he would have died around 2006 I think and was in his very late 80s. I didn't know Jack well, but he was always nice to me.
I'll put in a plug for Finemet. Quite pricey, but the frequency response is everything they advertise and the sonics are excellent. And their coupling caps are nice too. I had a strange experience trying some 10K p-p transformers for a Williamson amp. They really weren't suitable for that much feedback, but the open-loop FR was 20 to 20K, something I've never seen even in quality vintage OPTs. Wish I'd been building a PP 45 amp with no feedback!