Charles and Mikirob,
Yes, I am still totally open to and interested in Tekton. A speaker that efficient that might give me something like another 7 or 8 Hz on the bottom end is very appealing. And as I said, sebrof's speakers (although I know they are smaller than the Lore, but not that much smaller) were far more petite and decor-friendly then I would have imagined.
I do trust all those reviewers who love Eric's products. As a matter fact, Tim Smith and I corresponded a bit, not about speakers but about my issues with my amplifier versus the Dynamo that he was so fond of. He also thought that the Audio Note Kit 1 was a great choice  he has heard that gear at shows and has loved it. I think Tim is located in Canada and Brian Smith had a room at the Toronto show this past year that was very, very highly reviewed.
As I mentioned, I have also spoken with Eric twiceand in both cases was very impressed with his knowledge and his graciousness.
My first step is to get the Kit 1 healthy and then I should have a much better idea how it partners with the the capital's. As I said earlier, I was hearing A LOT of magic even with the amp in its current state, so I am very interested to hear how it sounds when it is working completely properly. |
Sorry, posted that previous comment prematurely. I also meant to say that even if my current speakers sound even more marvelous with my healthy, fixed up amp, I may still give one of Eric's speakers a whirl if I can be certain I can take the financial hit if I decide to return them. I think he charges a restocking fee, does he not? So I would be on the hook for that as well as for the return shipping.
By the way, Rob, talk about Tekton all you want  I really don't mind, I swear! :-) |
Almarg,
Can you be more specific where in the photo you are looking? Is this on the hard wired TAG strip or elsewhere?
Thanks!! |
Jetrexpro:
Yes, next kit, for sure, I'll test each part! |
Dan,
I'd never heard of those Class D kits. Holy cow, they're cheap! You could build one on a lark just to compare it, and, as you said, have a backup. And with that kind of wattage they'll drive anything. Never loved my Bel Canto Class D amp all that much but for $300 how bad can one of these be? |
Dan,
No apologies needed. Topic drift makes the world go 'round. :-) |
Dan,
Besides, if you can build a high powered amp that captures some of the SET magic for under $300, I think we'd all be interested. |
Technician seems to be zeroing in on the issue. Amp not putting out anywhere near its rated power. May be a tube issue. Very interesting. Brian in contact with the technician. New tubes coming. More later.
Again, can't wait to hear the amp at full operating strength! |
Tubegroover,
It's definitely an issue with the amp, but the question is what. Brian and the tech are on it.
Some signs point right now to a bad tube but we'll see. Technician said the driver stage looked good but the output stage wasn't delivering full power, which would certainly account for the clipping.
He also said it was a very neat build! :-D
Nice to think it's not something I screwed up, but we'll see. |
Jwm,
That is certainly what I am expecting/hoping! |
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Just got an email from Brian with a tracking number. He is sending the technician replacement tubes for everything but the 300 B's. He's also sending along a couple of 300 B bypass capacitors in case those are bad, along with, I think, a replacement power supply PCB just in case. He's also got detailed instructions for the technician about step-by-step testing instructions to take. I'm very impressed by Brian's email. He not only sells these kits, but he clearly has a deep understanding of how they work.
Anyway, I should have some more news tomorrow and I will update all of you.
Yes, lots of drama, huh? I'm going to try to sell the rights to Netflix For a miniseries, as long as they get someone much better looking to play the part of me. ;-) |
Al,
Thanks for all that meticulous attention and for the kind, positive comments about my build. I hand't worked with a soldering iron in a few years but once I got the cobwebs out I LOVED the building experience and have really caught the DIY bug.
Brian overnighted some tubes and new caps for the Power Supply PCB. The technician has them now and will be working on the amp tomorrow morning. I should know something tomorrow afternoon at the latest. I'm hoping it's something simple.
Yes, you are correct (and very observant, by the way) about the output transformers. The color of the wiring has changed since earlier versions of the kit and I had to ask Brian what the correct colors were. He told me that green is 0 (ground), blue is 4 ohm and yellow is 8 ohm. (I think that the earlier versions had a purple wire for the 8 ohm tap.) I deliberately didn't cut the unused, 4 ohm leads but bundled and shrink-tubed them in case I ever want to run a 4 ohm speaker.
The most challenging aspect of the build was that I was working with the previous version of the Assembly Manual, supplemented by a "beta" version of the latest Manual edition. Most of the design changes in the 2014 version of the Kit 1 have not been radical, although, as you noted, the Filament PCB has changed quite a bit (the whole heat sink configuration is quite different) and things like the lead colors on the OPT's have changed, too. So I corresponded with Brian whenever I had questions and, when I was uncertain at all, I tried to be extra careful not to solder anything until I was totally sure I had it right (although I'd have done that, anyway, given how slowly I tend to work).
By the way, a very pretty, updated manual is almost completed. I offered to send suggestions for the new edition to Brian and he accepted. I told him he could use photos from the blog if any of them are useful. So the bottom line is that future builders of this amp will have VERY nice, clear instructions to follow!
I don't think I mentioned this earlier, but the tech said that the amp wasn't putting out anything close to 8 watts, so there's something very funky going on with the power section. Again, I'm hoping it's simple! |
Saki,
Yes, when I think of it, I've started some doozy threads. The one about Ohm Walsh Micro Talls has run to over 2000 posts, last I checked. :-)
Of course, when I start thinking about all the productive work I could've accomplished when I was spending precious time posting to audiophile geek message boards, I'm not quite as happy with myself. ;-) |
Al,
There's a "+" sign on the PCB for the electrolytic cap positions and also the the band on the cap itself that shows you which lead is "-" so it's pretty hard to screw that part up. DoesnÂt mean I couldn't have done so, but I think those are probably okay. Thanks for the detective work, though! |
Cal3713,
Yes, no "my woofer's bigger than your woofer" allowed here! :-D
Waiting to hear back from the tech today... |
Well, Friends, no joy just yet.
The technician, with guidance from Brian, was unable to troubleshoot the problem, even with the complement of new tubes.
So, Brian and I will Skype early next week to see if we can troubleshoot the issue in that way in real time.
If not, Brian's going to get the amp shipped to Digital Pete, the fellow in Florida who does assembly of certain ANK products for those who (like Roxy54) want to buy a kit preassembled at extra cost. (Roxy has the 10th Anniversary Edition of the Kit 1 with the AN Copper Foil caps and the C-Core trannies.)
Pete's a real artist. Some of his assembly work is featured on the ANK website and it's gorgeous. And if by some bizarre chance I got something like a bad transformer (which, given that they're all pretested before shipping, shouldn't be the case) he'll know and be able to swap it right there.
My hope, of course, is that Brian and I can figure this out on our own.
This seems to be one of those one-in-a-million things. Brian told me that he sold two Kit 1's not long after mine and they turned out perfectly. Go figure!
I'll keep y'all posted! |
Jwm,
Thanks. As I said earlier, Brian has a deep understanding of these kits and I'm hoping that if we work methodically through all the possible issues we stand a good chance of sorting this out. If not, we'll get Pete on the case. |
Tomorrow is Skype day. Wish us luck! :-) |
Tomorrow is Skype day. Wish us luck! :-) |
Hi, folks,
Well, I got a personal message from one of you asking what's going on, so here's the latest.
Brian and I spent a total of about an hour and a half on Skype yesterday, spread over a couple of sessions. We went through all the static AC and DC voltages as well as some resistance measurements and everything that we checked looks good, except for one value (can't remember which one) that seems to drop precipitously after being measured. I don't remember exactly what we concluded about that one  sometimes it's just not easy to get a good reading on a solder joint.
We also tried putting a speaker load on one channel to check some AC voltages as the volume potentiometer is moved with a CD playing.
I have a few more measurements to do. Brian sent me a file of a sine wave (pure tone) that I have burned to a CD so I can play it while taking some measurements and adjusting the volume control.
Brian explained to me, again, that everything in the driver stage looks good. But when the technician here in Austin to whom I had sent the amplifier measured the output voltage with his scope, everything looked "squashed." "Like an elephant was sitting on the waveform," Brian said. So something weird is going on with the power stage not putting out full power.
If we cannot sort this out ourselves in another day or two, Brian is going to pay to have the amp shipped to Digital Pete, his assembly guy in Florida. Pete has built and done troubleshooting a bunch of these kits (and others) and has all the parts on hand. If, for example, I have a bad transformer or a bad 300B tube, he will be able to swap it then and there.
As much as I am eager to get back to listening to music again, I am again grateful to Sebrof for giving me the opportunity to use his speakers and determine that a speaker mismatch was not the issue. I am also very, very grateful to Brian, whose customer service is above and beyond amazing. He clearly gets a kick out of working on these things and keeping his customers happy.
And in the category of making lemonade out of lemons, so to speak, I am learning even more about electronics and how this amplifier works through this process. I'll be kind of disappointed if Brian and I can't figure it out long-distance, but as I said, I am also eager to get back to hearing that beautiful music. Brian said that Pete will turn it around really quickly if we do end up sending it to him.
When I run the additional tests, I'll let you know what I find. And I am hoping to see all of this resolved within the next week or so. |
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Oh, I also want to mention, for those of you who are interested, that Brian said that he is super curious to figure out what's going on because this is not typical of a build problem. Usually, he told me, either the amp is working fine or there's something really pronounced that goes wrong, like one very noisy channel or the amp frying due to a major wiring error or reversed electrolytic capacitor. But having an amp that "almost" or "sort of" works is just plain weird. I'm sure we're going to get to the bottom of it, though. |
Seikosha and Mapman,
Everybody agrees that this amp isn't working properly. The tech actually sent Brian video of his scope readings and they confirmed a problem. I played some bass heavy music for Brian and even over Skype he could hear the distortion when the volume went up. I think the experiment at Sebrof's confirmed that this isn't a speaker mismatch problem - we heard the same effects there. We're just not yet sure what's causing the amp to misbehave in this way and not put out its rated power. But I'm confident we'll figure it out one way or another. |
Smctigue1:
You know, that'll be an interesting thing to see and I'll let everybody know what I find.
Brian thinks we may be zeroing in on the problem, by the way. It's just that I've been to jammed up at work the past few days to do much testing! :-( |
We think we are zeroing in on the problem! More to come! |
Jbrrp1,
Yeah my Manley EL-84 push pulls in triode mode (20 watts) drove the De Capo's plenty loud with no trouble. |
So,
After three separate Skype sessions with Brian leading me through test procedures as well as some voltage meter checks on my own, putting a sine wave through the amp and taking a variety of measurements on the 300 B tubes, here's what we know:
We have verified that one suspect  that the volume pot might have been wired incorrectly (it's actually a somewhat complicated procedure involving six separate connections)  is fine. The volume pot wiring is good.
Most of the AC and DC voltages look perfect, even better than usual.
But there is some odd behavior with a few of the AC voltages vis-Ã -vis how things react when the volume pot is raised or lowered.
We also discovered that I have four ceramic capacitors soldered in the wrong position on the driver board, although these are not in the signal path and would not be causing the symptoms we've been hearing. (Brian is going to send me a set of replacement capacitors.)
At this point, Brian is pretty convinced that there is a problem with the driver board passing along a clipped or distorted signal. So we're going to do another Skype session and he will lead me through a step-by-step series of voltage checks on each stage of the driver board.
We should be getting there soon! |
Grannyring,
Yes, I am certainly learning a lot. It's a good feeling to know that I can take the bottom of the chassis off and fix or upgrade anything I want. Like, on a trivial letter, when I got the amp back from the local "repair" shop (sorry for the sarcasm), the speaker binding posts and input selector switch were both loose. On a factory built amp, I'd have been all upset. On my Kit 1, I just took the chassis bottom cover off and tightened a few lock nuts. What a nice feeling!
Almarg,
You are amazing: bingo and bingo!
What Brian explained to me is that the ceramic caps (C1, 2, 3 and 4) perform some sort of filtering function and aren't in the signal path at all. The reason there are two sets of pads in the PCB is that the PCB (which is an original Audio Note design) can accommodate more than one size/type of cap in that position, and the two sets of holes take two different kinds of caps. As they are right now, they're shorted out and not doing anything, but that doesn't effect the troubleshooting we're doing. |
Gsm,
Don't be discouraged. I'm not! Remember that I was working with an incomplete version of the revised Assembly Manual. You'd be working with something much more complete, refined and in line with the latest version of the kit. It's a lot of fun and, as Grannyring said, you learn so much. |
Almarg,
Right. If you go to the product page of the Kit 1 8th anniversary edition (not the C-Core 10th anniversary edition) and you click the download manual tab at the bottom of the page, you'll find photos in the manual of the populated driver board, using the older style, much larger caps. They would have used the top and bottom holes. The smaller sized caps being delivered with the kit these days for C1-C4 use the middle and upper holes, as Al pointed out.
On another note, Brian and I did more testing last night via Skype and confirmed that there are some very wonky AC voltage values on my driver board, so something is wrong there. That seems to be the source of the sonic problems I've heard! It's not impossible that I have some bad solder joints connecting the valve bases to the PCB, so I'm going to go through those and see if adding solder fixes the problem. But in the meantime, Brian is having Digital Pete, his builder in Florida, send me a finished driver board to replace mine in case I can't get mine sorted. I think the one he's sending has the standard Mundorf Supreme caps, but if the board fixes the problem, I'll replace them with my Silver/Gold/Oil caps.
Again, AN Kits customer service has been above and beyond. Although I'll have to swallow some pride to use Digital Pete's driver board in place of my own if I can't get mine sorted, it'll be a quick way of getting the amp in order! |
Well, I re-soldered all the joints between the valve base tabs and the pads on the Driver Board PCB but whatever's going on wasn't fixed because I'm still getting a distorted signal on bass-heavy material on the amp.
Just got an email from Pete (Digital Pete) Fulton in Florida that my finished driver board is shipping 2-day post tomorrow. So, I should be up and running over the weekend! I hope by comparing the two boards to at least figure out what the problem is/was with my Driver Board! |
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Okay:
I received my new Driver PCB from Digital Pete in Florida, ANK's designated builder for prebuilt ANK kits. It arrived on Friday. As you'd expect, the workmanship is first-rate.
I've managed to remove my driver board from the amp and hope to get Pete's board installed completely by Monday. I'll report back when I do. |
Hi, Guys,
Well, no joy yet. I replaced the driver board with the one that Pete sent me but it doesn't resolve the distortion issues. So I have packed up the amp and will ship it out to Pete in Florida tomorrow. He promises to get to the bottom of this.
I should mention that both Pete and Brian say they've never seen an amp behave this way. Usually it either works brilliantly or it fails miserably due to a build issue, as in "terrible noise in one channel," "really bad hum," "no sound at all" or "bursts into flames." This whole "sort of works" thing is just bizarre.
I'm sad not to have ironed this out on my own but it may just require someone with the required debugging expertise being able to get their hands on the amp in person. Pete should be that guy.
I'll update you when I know something. |
I could be shocked, of course, but I would be very surprised if this isn't some problem with the amplifier itself and not merely a matter of inadequate wattage. You may remember earlier in this endless thread that when the local technician attempted to fix the amp, he sent pictures of his scope readings to Brian at Audio Note Kits. Brian said that the scope readings looked "squashed." Something really didn't look right.
I would also be surprised if there isn't a legitimate problem with this amplifier because it's such a classic and time-tested design and the parts quality is so outstanding, from the gargantuan transformers to the beautiful, Audio Note silver speaker binding posts. Anyway, we shall see |
Mikirob,
Yikes, I'd like to read that, but I think I may have let my S'phile subscription lapse.
Nice to see Tekton getting a big, print mag review.
Looking forward to your De Capo impressions, Rob! |
Rob,
So you have a audiophile family, then? |
Please tell me I'm not the only one who obsessively tracks packages once you've shipped them.
My amp left Fort Worth at 11:00 am this morning on its way to Florida, by the way. |
Yes, Pete did send me a fully built up driver board, but replacing my board with his didn't fix the issues. So the amp is on its way to him. (Brian sent me the replacement board free of charge.) Yes, shipping a 50 pound amp to Florida (and insuring it) wasn't cheap, but I think it's the only way to get to the bottom of this, so it's worth it to me. IÂm confident, too, that Pete will figure it out. |
Pete has received the amp and will start working on it early next week. |
Brian said that there are three great, American mysteries:
1) The JFK assassination;
2) the aliens of Roswell, New Mexico;
3) Steve's amp
:-) |
Brian and Pete are going over the amp together: I should be hearing from them soon. |
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Well, for all of you (all 2 of you?) who have been on pins and needles to learn what was going on with my amp, here's what we know at last.
My build was on target - nothing wrong there.
Furthermore, Brian and Pete WERE able to replicate the distortion issue. This relieved my worst worry that they wouldn't be able to even reproduce the problem and we'd be back to square one.
The problem, it turns out, was with the output transformers. Brian and Pete have NEVER seen this issue in all the years they've been shipping and assembling these kits, but somehow or other these transformers had become magnetized and as a result weren't putting out full power. How this happened is even more of a mystery since these trannies are all very high quality and thoroughly tested before they ship! Brian is going to get these trannies back to go over them with his transformer manufacturer/designer to determine what happened to cause this very odd result. In the meantime, Brian is shipping two new transformers to Pete to install in the amp. So bottom line is that I should have a perfectly working Kit 1 in a week or so.
Let me again emphasize that Brian and Pete have provided superb support. And if the amp sounded great before, it should be really amazing with this issue sorted out.
Whew! |
Tubegroover,
As I said, my greatest worry was that Brian and Pete wouldnÂt be able to reproduce the problem - like those times I've brought my car in to the shop with a funny noise and the mechanic couldn't reproduce it. As soon as they confirmed that there was a real issue, I was relieved because I knew they'd take care of it. Brian said, "I'll make sure you're happy."
Almarg: such an interesting article, thanks.
Seikosha and Mikirob: Thanks for the good wishes. And Rob, really sorry my Stereophile sub lapsed. I'd like to read that Tekton Enzo review and may have to pick up a news stand copy. |
Joe,
I'm so glad you posted.
There's a local fellow who's selling off his tube collection, which must've been huge. I asked him about 6sn7's and he replied saying that he has the following to sell. I'm curious if any of these are worth picking up:
RCA Radiotron Electron Tubes, one labeled 6SN7GT, the other GTA
Sylvania, old Yellow box
Sovtek
Ruby tubes
What do you tube rollers think? |
I emailed Pete at TWL to see if he has any used or demo cables to sell. And Silnote seems a good, relatively low cost option. If you guys are of the consensus that the the Pangea cords aren't worth the trouble, I'll suppose I'll save up for something better. I know that in some things you get what you pay for! |
Mikirob: Happy to share the info. It's this fellow. He just happens to be local to me. I think I'll stay put with the RCA tube I have now. My next upgrade will probably be one of the Pangea power cords from Audio Advisor. I'm still using a cord cannibalized from a old PC! :-P |
Hey, Roxy,
Just received it today in fact. Unboxing pics will be on the blog shortly! Musical impressions to follow next week, probably.
:-D
Already gave you a shout out on the blog for making the suggestion to contact Andy... have a look. |
Roxy,
Warmed up the Kit 1 and played Buena Vista Social Club. Shut off the amp, removed the stock, Electro Harmonix (Russian) 6SN7 (wearing an oven mitt!!) and installed the RCA vintage (1940's!) tube. Played the same tracks.
HOLY COW, JOHN!!!!!!! :-D
What a tip!
Thank you!!!!!!!
How much better can this amp sound? It's kind of scary. ;-) |
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Charles,
I feel the same way as John. I am SO happy with my Kit 1! It has taken me beyond fiddling with gear to enjoying musical performances. And I am shocked by how just replacing that one 6SN7 tube kicked the amp up to a higher level of musicality. I never knew there was so much care and artistry lurking in so many of my records and CD's... it gives you an emotional connection to the listening experience because you appreciate how much of themselves the musicians and engineers poured into that recording. |
New post on the RCA 6SN7 tube is up on the blog! |
