DIY SET guys, ever use the Big Boy Blue Edcors?

Pez · « **on:** 31 Jan 2010, 01:13 am »

Just curious to see if any of you have ever used the Giant 9 lbs or better yet 11lbs big iron Edcors? I have been using the CXSE25-8-5K 11 pounders in my simple SE for quite a while now and even though I haven't done any direct comparison I can say these sound amazing! There is always more expensive ala James, Hashimoto and even Hammond, but I have yet to find beefier OPT for even a substantial amount of cash more. For those who believe bigger iron is better these seem to have the right stuff at a very reasonable price.

JoshK · « **Reply #1 on:** 31 Jan 2010, 01:49 am »

I have a pair of the edcors (push-pull 6.6K 60watts) but haven't used them yet.

Niteshade · « **Reply #2 on:** 31 Jan 2010, 01:53 am »

I have used the 25W Edcor SE transformers and they ARE good! Really, really good! The 60 watt P-P ones are great too.

Pez · « **Reply #3 on:** 31 Jan 2010, 02:46 am »

Anybody find any other iron that is as good/better than these OPTs? I'm sure there are, but I just find it very hard to spend $600 or more per transformer on some iron that's less than half the size of these and seem to use fairly comparable parts like the Hashimotos. I understand that the Hashis have many more taps than the Edcors and winding counts for something, but if you don't need 1.25k,1.5k,2k,2.5k, ohm input etc etc and 2,4,6,8,16 ohm output I fail to see why one would spend 3X more for less than half the iron.

JoshK · « **Reply #4 on:** 31 Jan 2010, 03:33 pm »

Hashimoto's $600 offerings are C-cores, which are a bit of a different beast. I am not sure they are worth the money, but they do get rave reviews.

You won't find too many guys apart from manufacturers that have side by side tested iron. I have a bunch of different iron in my collection but it is for different applications, so no side by side comparison could be done.

Tubelab.com has a write-up on testing of different budget iron and Edcor ranks very high on the list. He tests are objective though, and don't comment on the sound too much.

You can get a lot of opinions from folks on various tube diy forums, but most comparisons were in completely different amps I think you'll find. That mitigates the conclusion in my mind.

JoshK · « **Reply #5 on:** 31 Jan 2010, 03:49 pm »

I am trying to find a link I came across where Jean-Michel LeCleach (the horn guy) did a bunch of measurements of different output transformers appropriate for 300Bs in SE at the European Triode Festival '09.

His line-up was heavily biased towards DIY winders and what is easily obtainable in Europe, so no Edcors. However, there were some Tamuras and Tangos in the lineup, which is highly bespoke Japanese iron.

I noticed that Lundahl did very well in the run down. I happen to have a pile of lundahl iron for my Karna project. I was pleased to see 3rd party confirmation. You mostly have to go on word of mouth with these decisions, so it is based on who you trust.

JoshK · « **Reply #6 on:** 31 Jan 2010, 04:00 pm »

I happened to find the link through google. Funny I didn't see this page before, only the actual measurements. Their interpretation was different than mine.

http://www.triodefestival.net/index.php?page=etf2009-shootout

The measurement document (with commentary)
http://forums.melaudia.net/attachment.php?aid=1228

I am not sure square-wave results are the single highest priority attribute in an OPT, but it is related to bandwidth, which is among the most important IMHO.

JoshK · « **Reply #7 on:** 31 Jan 2010, 04:09 pm »

Minor rant/tangent/what-have-you...

I see the SET/Tube DIY crowd as having two polar sides, like in all things audio. On one side you have the engineers**, which base design principles on engineering principles and tend not to be very dogmatic about many things.

Then you have what I refer to as the dogma crowd. These base their findings on "audiophile group think". I am not trying to slight this crowd with this description, I am just trying to describe how I see their logic. They tend to base their logic on their own experiences and those of their mentors but there usually lacking in any measurements to back their assertions.

Now, with most things the crowd tends to be more centered. However, I say this as I intend to make one point. When making your decisions, if you choose to follow the "engineers" the chances of you making a decision you'll regret are in my opinion far lower than the other way around and chances are you'll learn 4-5 times as much in the process.

If at some point, you have followed the engineers for years and find you disagree with lots of their assertions, you can go your own way. Chances are you'd have learned to objectify your reasons, something you could never do following the other crowd.

There is many different ways of thinking among the engineering crowd, but at least you understand their rationale clearly, so you have something to base your decision on.

** I find it a bit humorous that there are "engineers" in a SET amp crowd, but I consider myself leaning more towards this end. Guys like George (tubelab), Gary Pimm, Steve Bench, and Pete Millett are all very technically proficient, design based on engineering principles and still design SE amps, although do PP amps too.

DaveC113 · « **Reply #8 on:** 31 Jan 2010, 04:16 pm »

Hey, I'm an engineer and I chose to build a SET!

As far as OPTs, I went with James. The only comparison I saw was Ultra-Fi claiming they were the best they found for a reasonable price. Besides weight of the trafo, there's also the materials used... the magnetic properties of the core, the windings, laminations, etc. all must have some effect on it's performance. Maybe someone who knows a bit about trafos can weigh in... I'm a ME, not an EE

JoshK · « **Reply #9 on:** 31 Jan 2010, 05:55 pm »

Yeah, there are a lot of engineers in the SE crowd. I just find it slightly ironic since SE amps measure among the worst in the traditional THD sense. However, there is a lot more too it than that. Also, everyone I know who's heard a good SE setup says the "tone", purity, or whatever is amongst the best they heard. Complaints are usually limited to bass or headroom.

I think it has to do with the harmonic profile of distortion. H2 and H3 in descending order are a lot less obnoxious than higher orders even if those orders are comparably small.

Designing a system around SE amps isn't as easy though, that is for sure. I don't want to limit my music choices to suit my amp. There would be no point in that.

Pez · « **Reply #10 on:** 1 Feb 2010, 02:07 am »

Quote from: JoshK on 31 Jan 2010, 05:55 pm

I think it has to do with the harmonic profile of distortion. H2 and H3 in descending order are a lot less obnoxious than higher orders even if those orders are comparably small.

Designing a system around SE amps isn't as easy though, that is for sure. I don't want to limit my music choices to suit my amp. There would be no point in that.

Good info here Josh, while I agree buying parts based on what audiophiles like has it's folly, but at the same time as you pointed out there's really no way to base such a decision when sonics are your main goal. I definitely understand that the "go with the engineers" mentality, but at the end of the day I don't give a damn how well my OPTs pass a square-wave. I do care about dynamics, realism, and all of the other hifi metaphors for loosely understood sonic attributes.

In reading the shoot-out I noticed the "best" measuring OPT was the Audionote AND BOY DO THEY KNOW IT! Those things are absurdly expensive.

As far as distortion I have always been a believer that too much emphasis is placed on THD, if you can't stand the sound of your solid state amp at 4 watts with a THD of .5% but love your amp at 4 watts with 5% THD then it doesn't matter one bit that the SS amp can pump out another 96 watts at <1% THD.

As far as designing a system that can utilize 5 watts effectively without tailoring your musical preferences to what sounds good on your system, I seem to be doing a pretty good job of it if I do say so myself.

The RM40s triamped with SS running the bass section and separate SET for the midrange and tweeters I am able to get +104 db from the listening position effortlessly with Rock, Orchestral, Jazz and everything else I have thrown at it. SET does far better when driving ribbons than most people realize. Lovin' it!

JoshK · « **Reply #11 on:** 1 Feb 2010, 02:17 am »

I can see where SET plus those ribbons would be a match made in heaven. Plus they present a near ideal resistive load....ideal for SET.

What I mean about the engineers, is not about square waves. What I was trying to say is that bandwidth is related to audio (sonic) quality in SE OPTs and that is semi-related to whether it can pass a decent square wave. The reason is technical and I am afraid I probably couldn't give a very good explanation.

Bandwidth limitations on the low end tend to make bass flabby as it is related to core saturation. The top end limitations leads to bleed down into the audio range and makes things sound less transparent, phasey or other very bad things.

The simplicity of the SET topology together with minimal stages leads to purity of sound, IMO. This is something other topologies can take a lesson from.

Scott F. · « **Reply #12 on:** 1 Feb 2010, 03:28 am »

Quote from: JoshK on 31 Jan 2010, 05:55 pm

I just find it slightly ironic since SE amps measure among the worst in the traditional THD sense.

You know, not all SETs horribly high in THD. A month or so ago Tekwiz held what used to be known as a McIntosh clinic. A bunch of us brought our amps in an Jeff measured them in the same way he used to way back when at the original MAC clinics. I took my 2A3 and my Welborne 300B DRD. Much to my surprise, then didn't measure half bad at all.

Full out my 2A3 did 5wpc into 8 ohms at 3% THD. On the other hand my 300B DRD amazed Jeff. at 5.5wpc it measured 0.64% THD. This was full output, pushed any harder the waveform clipped. At 4wpc she measured in at only 0.14% THD.

There is something about that old Lofgrin White circuit that is just right. It comes though as purity of sound. The great part of the DRD is you have only one passive in the signal path, a resistor (not counting the tubes and the xfmr).

Pez · « **Reply #13 on:** 1 Feb 2010, 03:49 am »

That is very impressive! Especially the Welborne. I'd love to see how the amp I put together would do. The highest distortion % wins right?

Pez · « **Reply #14 on:** 1 Feb 2010, 03:56 am »

Quote from: JoshK on 1 Feb 2010, 02:17 am

I can see where SET plus those ribbons would be a match made in heaven. Plus they present a near ideal resistive load....ideal for SET.

I can even biamp with the tweeter and mids run with Triode and 5 watts it still accomplish about 98 db which is pretty good still. Not nearly as effortless, nor as clean, but that is the benefit of triamping. In triamp it might be more than 104 db, but I'm using my iPhone to measure the output and the internal microphone clips around 104db. Either way it's "acceptable"

I have no doubt the Giant Big Blues have a lot to do with that.

Scott F. · « **Reply #15 on:** 1 Feb 2010, 04:07 pm »

Quote from: Pez on 1 Feb 2010, 03:49 am

The highest distortion % wins right?

....with SETs, you bet

Pez · « **Reply #16 on:** 1 Feb 2010, 05:05 pm »

Then it's likely that I have designed the best SET in existence. Ridiculous sums of money please!!!

mgalusha · « **Reply #17 on:** 2 Feb 2010, 02:10 am »

Bring it over some day.

Quote from: Pez on 1 Feb 2010, 03:49 am

That is very impressive! Especially the Welborne. I'd love to see how the amp I put together would do. The highest distortion % wins right?

Pez · « **Reply #18 on:** 2 Feb 2010, 05:43 am »

I definitely will.

I just finished the board tonight for the 2nd Simple SE.

This time went a lot smoother because I had the foresight last time to snap pictures of the front and back of the last board, all I had to do is solder and compare. I am going strictly triode on this puppy with absolutely no silliness with feedback or ultralinear.

I'll get in touch with you to figure out a time.

jrebman · « **Reply #19 on:** 6 Feb 2010, 05:07 pm »

Mass of iron doesn't guarantee anything in an SE transformer except bragging rights. Transformer design is a science as well as an art in balancing compromises against each other. Which is to say all the little details add up and there's no guarantee that a lot of iron is going to sound any better than a different set of compromises in a smaller package. There is also such a thing as too much of a good thing.

Of course, if the Edcors sound good in the SSE, then by all means, stick with them.

And yes, SET and ribbons sound wonderful together!

You're also on the right track, IMO, in leaving the CFB and all that out of the SSE.

When Mike gets the little package I just sent him, it will be interesting to hear how that compares to the 11-pound transformer amp, but of course they are two entirely different beasts, but it should be interesting nonetheless.

Looking forward to hearing how the new iron works in the SSE though.

-- Jim