Brf,

That's interesting and perhaps a bit surprising but one has to keep in mind that technical specs and matches alone do not dictate how good something will sound, only that the things involved are able to do their own thing together technically to the best degree possible. Each thing is different and personal tastes and preferences will vary. So technical considerations can be used to steer one in a good direction with a better chance of success perhaps but alone cannot guarantee the desired results.

I;'ve never heard either Decapo or Coincident so I have no clue how they actually sound. On paper though, Coincident would seem to be better suited for tube amps in general. Of course SET amps up the ante for teh speakers to be able to deliver on just a few tube watts, so not all tube amp friendly speakers are necessarily the best match for a SET.

It all depends, like usual, on an individual's own personal goals and perhaps to a lesser but still important extent their budget.

mapman February 06, 2015 16:21

Rebbi, I’ve owned both the Reference 3a de capo i (non be version) and the Coincident Triumph Extreme 1 (not the Mk2) and I can tell you (specifications notwithstanding) that the Reference 3a de capo i was easier to drive and more dynamic than the Coincident when driven by a 15w SET in my secondary system. Please note that I have not heard the Mk2 version of the Coincident.

brf February 06, 2015 15:37

Rebbi,
I agree with other posters in thinking that you should not give up on your new amp, but change your speakers. As you know, I use Klipsch Epic CF-4s, but I also have 2 pair of Celestion monitors, the Kingston and the SL6si. both of those are about 86db efficiency, and are woefully underpowered by the Kit 1 sad to say. I heard that it might work, but it didn't. When I want to listen to them, I listen with Mac solid state in a smaller system.
Concerning the power cords, I use the better Pangeas from Audio Advisor for the whole system, but they do fortify the bottom end, but not drastically. If I had the funds, I would experiment with other brands, but the price/value quotient of the Pangeas is very good.
I suppose I also am prejudiced concerning the DeCapos. I bought them after reading so many positive things about them, and set a new personal record for how quickly I got rid of them. I found them to be kind of plummy and dominant in the bass, and not very coherent...personal taste.
If I didn't have what I have, I would buy Coincident.

roxy54 February 06, 2015 04:44

Gsm: Yes, Tekton's offering a 60 day trial period, for example.

rebbi February 06, 2015 02:43

Rebbi: If you decide to look for different speakers, many manufacturers who sell direct - Tekton, Zu, etc - offer extensive in-home trial periods of 30 days or more.

gsm18439 February 06, 2015 01:49

Charles

No doubt. Two radically different approaches. The amp is just one ingredient in the recipe. I find with the amp I'm using at least that it allows the other ingredients to shine through including the clean just a touch warm but detailed sound of the audio ref tube preamp. My speakers dictate the approach with the amp.

In my other system. I have smaller versions of the same speaker run of tuba audio design hibachi amps and I use a tube dac to achieve a similar sound. Lots of ways to make good soup. Building around a set is one I might try sometime but I would expect similar results as well in that I am always shooting for the same target in terms of how things sound but perhaps to different scales in different cases depending on the room

mapman February 06, 2015 01:24

I'm open to any interesting discussion concerning music and good sound.Mapman I know you're a strong advocate for class D amplifiers and reall y enjoy them. I say what ever gets you the sonic result you seek, go for it. For my self I've never heard a Class D amp that comes close to what a good quality SET offers. I fully understand this is purely personal and simply preference. If a class D amplifier comes along that truly equals a SET in the areas that are so important to me I'll be among the first to acknowledge this achievement and buy it proudly.Both types bring joy to their respective owners but they are very different sounding approaches.
Charles,

charles1dad February 05, 2015 23:24

BTW,

I hope Charles does not mind us hijacking his thread to talk about these things.

mapman February 05, 2015 22:06

Reb, yes I thought you did something like that at some point but was not sure.

That BC is OK for the price but not the best match based on input impedance for a tube pre-amp, so more might have been possible there. Of course all combos will sound somewhat different.

FWIW I leave the power on with my Class D amps all the time in that they draw virtually no power when idle but mostly to avoid having to turn them on. I also keep my SS DAC on most of the time. I do not play CDs, but to play music, I just turn on the ARC tube pre-amp and touch my SB touch and that's it. Just saying.... There are many ways to skin the cats.

mapman February 05, 2015 21:53

Map,
I had a Manley Mahi tube pre with a Bel Canto S300 Class D amp sometime ago... used it with my Ohm speakers, in fact. It was a pretty good combo. But I built an integrated amp because at this stage of things I got tired of having to flip 6 or 7 switches just to play a CD. I might migrate back to separates at some future time, but at this point simplicity is most appealing.

rebbi February 05, 2015 21:48

Also I wonder if anyone has achieved optimal SET like performance using a tube pre-amp with SS amp, maybe Class D, to add the tube magic but also be able to drive most any speaker of choice?

I do that in my system and think it works pretty well but my SET listening experience is limited to just a few auditions at shows, etc.

mapman February 05, 2015 21:38

Another possible solution is the Zeros impedance matching transformer but these would add some cost that might just as well be applied towards a better match in speakers.

mapman February 05, 2015 21:33

Mapman,
If Rebbi wants to keep his speakers a sub is a viable solution. I know many listeners use them quite sucessfully. I've used them in past systems but I prefer SETs with a load friendly speaker without question. As always there's more than one path to reach a goal.

charles1dad February 05, 2015 21:26

Don't turn back. Forge ahead. Offloading the bass to a powered sub or two with the existing Decapos would likely solve your problem with the best of both worlds and leave little to want. Martykl is the champ of integrating tube amps with subs around here. Maybe see what he has to say.

mapman February 05, 2015 19:42

Rebbi, first, I am very happy for you on your successful build of the AN amp. Hearty congratulations!

I at times have similar issues, and have found a compromise that works for me. I don't recall if you have kept your Manley amps. If you have, you might consider what I have done.

If I know I'm going to listen to the demanding type of music on any given night, if you can set up your Manleys, with their own power cords, IC's, and speaker cables, you can change amps out in about two minutes, and listen to your heart's content. Until you want to listen to music more appropriate to the SET.

I know this sounds exensive, but it depends on how you go about it. I built my own power cord, and bought (very reasonable, at the time), two pair of 12' Tempo Electric solid-core silver in Teflon tubing speaker cables, which were about $1600 for both then. I recommend these cables very highly, by the way, and sold Auditorium A 23 cables to make the switch, and I'm glad I did.

Anyway, it's a compromise that you might consider, another option. Going to more appropriate speakers, though, may be the best solution for you, as was previously mentioned.

Best regards, and happy listening,
Dan

islandmandan February 05, 2015 19:41

Rebbi,
Members here of whom I hold in very high regard, are of the same opinion as I,
which is that you keep (your baby:) the amp and switch to appropriate speakers.
Give SET amplification it's due fair chance. You'll most likely never leave it.

isochronism February 05, 2015 18:09

Rebbi, AN speakers don't have to go in corners to sound good. Please hear them with your amp. As Charles said there are some great speakers as well, Coincident among them but there should be a special synergy with AN speakers.

jetrexpro February 05, 2015 17:50

Rebi,

It does sound like a different powercord is worth trying (I won't specifically comment on the old computer cord experiment). I picked up my Cardas Golden Reference PC for $225 used. There are a good number of used power cords listed on Audiogon, and that's one of the safer things to buy used in my view. You may get more bang for your buck that way. I have heard good things about the Pangea cords but have never tried them myself.

And Charles, it's good to know that the EML XLS tubes are a drop in replacement. They sounded significantly better than any other tubes I tried in my Diavolo. They are not dirt cheap (around $700 a pair new I think), but I was lucky enough to find a used pair listed here and from a seller 20 minutes from my house here in Denver. I'll never look back.

Rebi, you should definitely consider trying a pair of the EMLs as a less drastic measure, particularly if you really like your current speakers. I don't know the technical details, but I think the whole point of the 300B XLS tubes is to provide the magic of a 300B with a little more power.

dazzlingmd February 05, 2015 16:34

Rebbi,
Given the fact that your speaker is realistically an 86 db speaker, it's a tribute to your AN Kit to get the wonderful sound you're hearing. That suggests the amplifier's power supply and output transformers are very good quality. With a more suitable speaker match, look out! It has to be a good amp to out perform your former Manley in the way you describe.You obviously made a wise choice in choosing to build this 300b SET. The list of very happy SET converts seems to be expanding on this site.
Charles,

charles1dad February 05, 2015 16:30

Jet,
You're right, there is a wide variety of of SET friendly speakers to choose from.I just mentioned Tekton and Coincident as proven examples. The SET amps will "sing" if given a benign speaker load designed to mate with them.

Dazzlingmd,
The EML XLS is a drop in 300b replacement. You are absolutely right, this is a superb tube, I love it in my Frankenstein.

Hi, Thaluza I'm very happy for you!It's good to know the Frankenstein has worked out so well in your system. You'll enjoy and appreciate it for many happy years.
Charles,

charles1dad February 05, 2015 16:00

Thanks so much to all of you for chiming in – I love you guys. :-)

Charles: If the Coincident Triumph Extreme II happened to be about $1000 less expensive – that is to say, a more or less even swap for my the De Capo's on the used market, I would jump at it. I may talk to Israel anyway just to see what he thinks. Now, for what it's worth, Brian really thinks that his EL34 push-pull amp is a spectacular example of what push-pull can be when implemented with extreme care and top-flight parts. Where I am at the moment – and this varies throughout the day :-) – is that the Kit 1 is pretty fabulous and I'd be better off finding a pair of speakers that really allow the amp to show what it can do.

Dazzling – It's interesting what you said about the power cord. The Kit 1 doesn't even include a power cord in the kit. I'm guessing that Brian figures that at this level, people are going to go out and try a boutique power cord, anyway. I've never tried a fancy power cord and I, too, don't want to get involved in debates about the efficacy of "wires." I will say, however, that I believe that at least speaker cables sound different. Audio Advisor has their Pangaea line of very reasonably priced power cord upgrades and I might try one of those. Right now I am running the amp with a power cord cannibalized from an old computer, I think. (Please don't start throwing things.)

Jet –
I would love to try Audio Note speakers – I would even try building one of their kits. The problem is that corner placement just isn't an option in my current room. It might be, one day, but right now it's not a dedicated listening room and I don't have that kind of speaker placement flexibility.

Al –
I completely and totally agree with you. And in all the exploration I had done on various forums about this, I couldn't remember who it was or where it was that someone (you) posted the National Research Council measurements. The other day I googled something like "De Capo sensitivity measurement graph" – and I found it. And yes, you are correct, in their measurements (I don't have enough of a technical background to understand why their measurements are so much different than the ones that John Atkinson did years ago) the De Capo is only 92 dB efficient across a very narrow frequency band from about 1000-2000 Hz! Averaged, it's only 86 db. That, I think, has to be a lot of the issue.

Thaluza–
Thanks for chiming in. The Kit 1 does sound better as it breaks in, no doubt about that. I was listening to some of my favorite music last night and it sounded breathtaking – I mean, really, I was mesmerized. The material that is giving me trouble, again, is pop music with what is probably "pipe organ" frequency synthesized bass. With that music, unless I listen at levels lower than what energize the room, some pretty ugly clipping distortion sets in.

One other question, guys: I know a lot of people turn their noses up at Klipsch, but do any of you know anything about their current lineup?

Again, thanks for the brilliant comments and suggestions.

rebbi February 05, 2015 15:57

02-04-15: Rebbi
I am running Reference 3A De Capo speakers. They are rated at 92 db efficient, but I am beginning to think that this rating is "optimistic."

Rebbi, first, congratulations on the successful build!

Yes, the 92 db rating is significantly optimistic according to measurements by the well regarded National Research Council of Canada, which you may recall I linked to in my post dated 10-20-14 on page 5 of your "Greatest Bargain in SET" thread. The disparity of slightly greater than 6 db (on a per watt basis, as opposed to the less meaningful 2.83 volt basis), corresponds to about 4 times as many watts being required to produce a given volume level.

Regarding the first of the three courses of action you described (living with the limitations of the Kit 1 on certain recordings), a point to consider is that driving a speaker with a severely clipped waveform not uncommonly results in destroyed tweeters, especially if it is done repeatedly within a a short amount of time. Even though clipping is most commonly induced by high amplitude signals at low frequencies, the clipped nature of the waveform results in an abnormally great amount of energy in the treble region, which is not present in the original signal.

So if you were to settle on the present speaker/amp combination as your long-term solution, that concern would always be on your mind, and I suspect would often interfere with your enjoyment of the music.

I'm not particularly familiar with Omega or Tekton speakers, but if it were me, consistent with the comments by several of the others I would put the Coincident Triumph Extreme II high on my short list, if its $3400 listed price (converted to US dollars, and including stands) is not prohibitive.

Continued good luck. Regards,
-- Al

almarg February 05, 2015 15:33

You have many great speakers to choose from. Audio Note Speakers would be the natural choice with an Audio Note amp. Not everyone likes AN speakers. To find the speakers you will love I would suggest taking your amp with you when you audition speakers. That is what I did and I have been a happy camper ever since. If you find speakers that are above your budget save for the speakers you love. don't compromise -jet

jetrexpro February 05, 2015 13:24

Rebbi, Sorry, and mildly surprised, to hear that your AN 300B is not driving your deCapos entirely to your satisfaction. I have no experience with the kind of music that is not being reproduced acceptably, but I can imagine that a sustained high current demand could be an issue.

I agree with Charles that you are probably not going to be satisfied with another push pull amp having experienced what a good 300B is like. In addition to my deCapos, I have a pair of Coincident Triumph extreme IIs which I prefer over the deCapos. They are dead neutral and have better coherence than the deCapos. They are very fast and revealing. However, they come up for sale rarely, and I would not recommend them for use in a room that tends to have a live acoustic.

brownsfan February 05, 2015 12:15

Rebbi,

There might be somewhat of a speaker mismatch, but it could also be that your amp is still breaking in.

My speakers are from Coincident, with 93db sensitivity and 10 ohms nominal impedance. I believe yours are 92db and 8 ohms, which is not far off from what I have.

I am breaking in a new pair of Frankensteins that are an excellent match for my speakers. However, for the first 100 hours or so, the bass seemed a bit distant, disjointed and unfocussed compared to my other amp. I kept switching in my other amp because I missed the bass. Music at higher volumes was also on the harsh and shrill side with the Franks at first. However, the bass has suddenly improved as has everything else. I am experiencing better tonality, and greater weight and authority. I'm listening to some pop and rock this evening at 85 to 90db listening levels and I am thinking my system has never sounded better with this type of music! No more harshness, no more lack of bass.

If you do switch speakers, I would not hesitate to recommend a speaker from Coincident (I haven't heard Tekton), as Charles suggested.

thaluza February 05, 2015 06:21