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

Rebbi,
your description of live music via the 300 B amplifier mimics my experience upon first exposure. It was simply more realistic and natural I could not return to my former amplifier. As you discovered, SET is more clear, transparent and resolved. Wait until you try the Higher quality 300b tubes that are available, you'll be thrilled.

charles1dad February 05, 2015 02:34

Rebbi
As often pointed out, the chosen speaker is critical to getting the most from a SET. The el34 amp might be the match for your speaker but won't sound like your 300b as you enthusiastically describe. I would personally get a more Compatible speaker, Tekton or Coincident and truly exploit your amplifier's complete attributes and virtues . You have heard the special purity and beauty of SET. You won't be happy with less anymore for now on IMO. Build your system around this special 300b amp. That's what I did.
Charles

charles1dad February 05, 2015 02:16

I'm certainly no expert and new to SET amps myself (although loving it), but my new (to me) Art Audio Diavolo is pushing its limits to drive my Merlin speakers, and I did 2 things that helped. First, I inserted some EML 300BXLS tubes. I don't know if the Kit 1 can take those or not, but my understanding is that they give you a little more power if so.

Second, on a whim I tried a different power cord. I'm personally VERY SKEPTICAL about things like power cords making a difference (or a power cord having a "sonic signature" of any kind, but I'm not trying to start a debate here. But I substituted a used Cardas Golden Reference power cord for my stock cord, and it immediately provided more bass weight and it became harder to clip the amp. Even before the power cord change, I had to crank it up to near ear-bleeding levels to get it to distort like you're talking about, but the power cord made a difference there as well. And to me there's some logic in that--a more substantial power cord could provide some assistance to an amp that is pushing its limits.

Good luck with your continuing journey, which I've been following closely.

dazzlingmd February 04, 2015 23:04

Hello Charles and fellow SET-heads,
Okay, it's time to seek your advice.
My Audio Note Kit 1 300B SET is completed and making music! I want to thank you all for your guidance and inspiration and ask your advice.
The amp sounds beautiful, increasingly so as it breaks in.
The words that most come to mind are "pure" and "clear." There is a pristine, crystalline quality to the music that is really something. In fact, I would not describe this amp as "tubey"romantic or rolled off in any way. It sounds fast, clean and modern. Additionally, its ability to suggest ambience and spatial relationships is through the roof. I was listening to a live album with which I am intimately familiar and was shocked by how much more live it sounded than my old Manley push-pull amp. Tonality is great, too. And this is with the entry level, stock Chinese 300B's!
So in sum, this amp is a MAJOR sonic improvement over my old gear. Yay!
Now for the dilemma and advice.
For much of my music, the amp sounds beautiful. But for some of the pop music that I like to listen to, especially anything with VERY deep, sustained, hip-hop style synth bass, the amp will clip very noticeably when played at room energizing levels. Bass breaks up and the singer sounds like they're gargling. For example, Lorde's album "Pure Heroine" is full of this kind of material, and so is Sade's "Soldier Of Love." Played at lower than normal listening levels, they sound great. But by 11 o'clock on the volume pot, which is about where I'd be for my typical listening levels with this amp, clipping sets in on those CD's. By the way, most of my LP's sound fantastic.
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." Granted, the Kit 1 will drive the De Capo's to more than satisfying volume levels in my 11 x 16 x 8 foot room, but with some music, such as the aforementioned, I have to dial the volume back to avoid clipping.
I see my options as follows:
1) Stick with my current gear and accept that a 300B SET amp paired with the De Capo's has limitations. I spoke to Tash Goka at Reference 3A, by the way, and this is essentially what he confirmed.
2) Stick with the Kit 1 and look for more efficient speakers. I've thought of Omega's or Tekton Lore's. The problem here is that I cannot lay out money that I don't have in hand, so I'd have to take a leap of faith and sell the De Capo's to finance any new speaker purchase. Your thoughts here? Let's say I could get between $1500 to $2000 for the De Capo's. What would you look at?
3) Brian has offered to take the Kit 1 back if I'm not entirely happy and get me their L4 EL34i push-pull integrated kit with the C-Core transformers, which is supposed combine the virtues of SET the gutsiness of push-pull. It puts out 35 watts per side and would certainly drive my De Capo's well.
Eager to hear your thoughts...

rebbi February 04, 2015 19:42

Thank you Charles...very much appreciate the help!

zephyr24069 January 26, 2015 19:49

Hello,
My experience for about a 15-20 year period had been extensively push pull tube amplifiers after migration from solid state. My most recent PP amp purchase was Bill Baker's Response Audio Bella Extreme. This was a class AB 6550/KT 88 100 watt(60 watt in triode mode). This was one of the very best PP amps I'd ever heard(and I've heard quite a few). Curiosity led me to explore SET amplifiers and it was all over after that introduction.

I was instantly captured by what a 8 watt 300b SET added to my system, this exceeded my expectations which were high. It's been well over 5 years since the switch and if anything I'm more impressed as time marches on. 300b SET just pushes all the right musical/emotional buttons for me and I'm totally content.

The Lamm PP amplifier pictured above was a generous loan from a friend who was curious about my impression of it. Honestly, the Bella Extreme is better sounding to me. The 300b SET beats both in terms of naturalness, emotional conection and is just more realistic and captivating. Zeyphr there are many very good tube amplifiers available and with some patience I'm certain you'll get just what you want.
Good Luck,
Charles,

charles1dad January 26, 2015 12:41

Charles: Thanks for your reply on my other post inquiring about possibly moving to Ayon tube amps. You have quite the collection of tube gear and this thread gives alot of material that I've yet to cover. Of all your amps present and recent, which are your favorites and how frequently do you swap in/out and for what reasons? Thank you!

zephyr24069 January 26, 2015 10:13

Hi Rebbi,
Congratulations on successful completion of your kit building project,you must feel very gratified. I am eager to read your impressions of this 300b SET with your speakers. Curious to know how it differs from your former Manley amplifier.

charles1dad January 26, 2015 07:25

Charles:
My Audio Note Kit 1 is built and burning in. I'll have sonic impressions after a couple of weeks of burn-in. Thanks for all the advice.

rebbi January 26, 2015 02:58

Hi,
Crubio I have only heard the XLS and the mesh versions. Both of these are excellent IMO, but I would suspect the standard 300b is very fine as well. EML is top quality based on my experience.

charles1dad January 25, 2015 21:21

Hello,

I wonder if you compared the EML 300b to the xl version, much difference
In the sound?

Thanks,

C

crubio January 25, 2015 18:45

Hello Chuckie,
I sincerely appreciate your very kind comments. I'm just genuinely satisfied with music reproduction in my home. Once I got the SET amplifier everything took off and subsequent additions revolved around that foundation. The focus is to obtain a natural sound and all choices made were based on that objective. Given your system I know you can understand that direction.
Charles,

charles1dad January 22, 2015 20:32

Excellent system Charles1dad totally and seemingly painstakingly matched. Every component carefully chosen and expertly introduced I am sure. Congradulations on such a magnificient system!

chuckie January 21, 2015 17:37

Hi Jeff,
I lost my phone last week and I'm currently out of town. I'll call you tonight.

charles1dad January 15, 2015 20:05

Charles been trying to get a hold of you.

jwm January 15, 2015 14:12

Hello Cal,
I believe you'll be very happy with this amplifier driving your Coincident SE III speakers. Please feel free to post your impressions here if you'd like to. Thanks for the Kenny Burrell tip, I'll find a copy of it. I don't know the effect of the bypass capacitor for the power supply caps.The other modest changes the previous owner made shouldn't hurt the sound at all.
Congratulations on finding the Frankenstein "used", they're relatively rare.
Charles,

charles1dad January 10, 2015 19:33

And the Franks are finally on the way... just ran across a pair on USAudioMart and got them on day 1. Not very good for bargaining, but I'm happy to get a chance to hear the SEIIIs with these amps.

http://www.usaudiomart.com/details/649169950-coincident-frankenstein-ii-set-mono-poweramps/

Also, since people in here have periodically discussed Kenny Burrell, interested parties should check out Guitar Forms if you haven't already heard it. Some great mellow work from him.

cal3713 January 08, 2015 20:40

Charles,
You're most welcome. I'm getting there with the build. Got some more wiring to finish and, with any luck, it'll be done by early next week, depending on my work schedule.
A few of my tubes were back-ordered when the kit shipped. Those just shipped out to me today from Canada! Hooray!

rebbi January 06, 2015 01:31

Hi Rebbi,
Thanks, by the way I have enjoyed reading your well done AN kit building blog. Very interested what you hear compared to your former Manley push pull amplifier.
Charles

charles1dad January 06, 2015 01:26

Charles,
Just a heads up that there's finally a review of the Dynamo 34SE in February's TAS. I'll discuss it in the "Greatest Bargain In SET" thread.

rebbi January 06, 2015 01:11

Scott,
It occurred to me you're probably referring to the Spatial OB speaker pictures, oops, sorry.

charles1dad December 17, 2014 12:10