Which speakers are higher efficiency?

Hi, I am in the market to buy a high efficiency speakers to match my 300B with given 15W output. When I do some search online, I have 2 speakers in my mind:

Reference 3a Grand Veena Loudspeakers
Efficiency: 90 dB. 1Watt/meter.
Frequency response: 36Hz - 20 kHz (+/-) 3dB.
Up to 100 kHz high frequency extension.
Bass loading: F3@ 36Hz., tuned port,
quasi-second order, -15dB at 20Hz.
Impedance: 5 Ohm (+/-0.5 Ohm).
Power handling: 200 Watts RMS.
Phase: Almost constant at 10 degrees @94dB, wide band.

Focal 1037be
Type: 3-way bass-reflex floor standing speaker
Frequency response (+ or-3dB) 38hz-40hz
Sensitivity (2,83 V/1m) 91dB
Nominal impedance 8 Ohms
Minimum impedance 3,5Ohms
Crossover frequency 350Hz/2000Hz

Just look at the number, Focal 1037be is more efficiency, b/c it gives 91dB v.s. Reference 3a Grand Veena only give 90dB. Is that right? or am I missing something here?
Or can you guys suggest a 4~6k high efficiency speakers for me?
Coincident Partial Eclipse. Very nice. Monitor speaker coherence, but with bottom end. All Coincidents are made to run off 8 watts, so you're fine on the power end.
The efficiency/sensitivity is about the same. You could go with either.

From my perspective, the impedance is more telling. The Focal have a nominal impedance of 8 ohms, but the minimum impedance is 3.5 ohms.

The Reference 3A Grand Veena have a 5 ohm nominal impedance, but the minimum impedance is 4.5 ohms (8 ohms +/- .5 ohms).

It will be easier for the tube amp to produce a balanced frequency response on the Reference 3A Grand Veena, and therefore I'd select the Reference 3A Grand Veena between the two under consideration.
I would second what Tvad said. On the point of the efficiency spec, you don't know if they were measured the same way under the same conditions with the same equipment. And the figures are so close. Six of one, half a dozen of the other on this. Because of that, I would look at the impedence dip for further information as to which might be more efficient or less demanding on an amp.
Just how loud do you expect to play the speakers? If they are 90 at one watt, then 93 at two, 96 at 4, 99 at 8, and 102 at 16. This is not terribly loud, the Focal is capable of much higher. If I was wedded to the amp I would look for more efficient speakers, especially in a large room. If you have a small room, do not play a high volume or demanding musical works you may get by.
Stanwal is right, the Focal will play louder, but the uneven impedance curve suggests they could sound "bright".

I would prefer a balanced frequency response at a lower volume, if that's the trade-off.
I was just about to post a similar comment to Stan's, when I saw his post. I don't think that 90db speakers are sensitive enough for use with 300B or other low powered amplifiers, unless you are in a small room, listen from no more than around 8 feet away, listen to music that has narrow dynamic range, and don't listen at high volume levels.

To realize the same peak volume levels with 15 watts that the Grand Veena's can provide at their rated 200 watts, you would need speakers with 101 db sensitivity.

I do agree with the others that for best compatibility with a tube amp you should give preference to speakers with the highest possible minimum impedance.

-- Al
Also, the Grand Veena's are actually about 1 db MORE sensitive than the Focal's, assuming the specifications are accurate. Their 90db rating at 1 watt at 1 meter, coupled with their 5 ohm impedance, means that they would reach 90 db at 2.24 volts into the 5 ohms. That corresponds to 92 db for the 2.83 volt input that the sensitivity of the Focal's is spec'd at.

The reason that many speakers have their efficiency spec'd at an input of 2.83 volts is that 2.83 volts into an 8 ohm impedance corresponds to 1 watt. However, if the spec is based on input power, not voltage, the impedance of the speakers being compared has to be factored in, to make the comparison meaningful.

-- Al
The specs are too close to tell you anything meaningful. Speakers with very close specs can still sound very different from one another. While you can make a short list by using specs to weed out non-contenders these specs are close enough that you need to actually hear them to determine your preference.

What amp do you have? 15 watts is a lot of power from 300B amps unless it uses more than one tube per channel. Are you sure it is 15 watts?

If your budget is up to $6K I would get some horns like Avantgardes or good lowther based speakers like the Beauhorns. You want to be in the +100dB range for efficiency to work with 15 watts, not 90dB.
Almarg sez:
I don't think that 90db speakers are sensitive enough for use with 300B
May I paraphrase? "90dB speaker ARE NOT sensitive enough for use with a 300B (you sure about the 15W?; Isn't more like 12W?)

Look in the direction of horns. Eliminate everything under 95-96dB. Regards
Phase angle is Key. Too large a phase angle results in a lower power factor.
With some speakers having huge phase angles, you can easily turn a 100 watt amp into 30 or less. Tube amps don't like heavily reactive loads, (capacitive or inductive, don't 'member!)
That is the REAL indicator of 'easy to drive'.
If you can see the impedance and phase angle data that would help, at least from a purely technical viewpoint.
Of course, what will happen is the speaker which sounds better will also have the worst numbers. Don't buy Specs.
Magfan, what are you telling the guy??? Don't buy specs??? The guy has 15Watts of amplification, the phase angle is hardly his problem:).
And, please believe me, the speaker with the worst specs will not sound best -- not unless the specs are wrong. Regards
Drinking from the label is usually a recipe for disappointment.

Despite the specs, this isn't a difficult question to answer, as the two speakers being compared here have different characteristics in terms of what they interface with best in terms of an amplifier. Focal speakers in general need a good bit of power to come alive in a top to bottom way, and I don't consider them low (less than 30 wpc) power friendly for the most part. The Reference 3A Grand Veenas can absolutely sing with lower power, it's more a speaker that thrives on quality, as opposed to quantity.

This isn't to say one is better than the other, only the individual can answer that for themselves. But, I will say my personal opinion is that the Grand Veenas are one of the most beguiling speakers I've heard in a very long time.
None of the loudspeakers listed is a good match. Sure music will be made but amp will alter frequincy responce plus amp will be clipping much of the time. 4-6k You have options for a proper matched loudspeaker. Since I manufacter such loudspeakers but best to let others mention brands.
I don't know the Grand Veena, but used to own Ref 3a deCapo loudspeakers. The deCapos aren't hugely sensitive, but they present a very easy load. The minimalist x-over is said to contribute to this. Bottom line: they work very well with 300Bs (no obvious deviations in FR), but have limitations on dynamics and ultimate spl. If you can live with (and listen within) these limitations, Tvad's original comment is right on. If you can't, Johnk and Gregm offer good advice.

Agreed with JohnK, neither two speakers you are a good match for a SE tube amp. Sensitivity is only one factor you must look at; more importantly is a benign impedance curve.

You should consider one of Johns speakers (KCS), Cain and Cain or Carder sound (and many others)

Gotta say I agree with Johnk and Gregm on this one. You need at least 95dB to make those 300Bs work really well, and I would almost say you need 98 (though it would depend on the impedance curve (and at that level, phase angle may come into play :^) but I'll defer to others on that)). Anything below or with a large impedance range with the low impedances in the bass and you will be risking serious disappointment (especially in the bass). I think the Coincident Total Eclipse are good high efficiency speakers in the 'box speaker' format, but my heart belongs to horns, which can come in all kinds of flavors. I'd think for $4-6k you could do yourself very well, either by buying something used off the 'gon or buying speakers custom-made for you direct from the manufacturer (disclosure: I've never purchased any speakers from any manufacturer who mentions himself on this thread (or is likely to going forward for that matter) but I've seen some of his creations in photos. Other builders are those who deal with BLH (back-loaded horn) designs. You can check Frugal Horn for some DIY designs, though there are some builders who will build a set for you, sometimes ones which are tweaked/improved beyond the original design. You might also dig around the archives here and over at AudioAsylum.com (the High Efficiency Speaker Asylum). There will be lots of ideas in both places.
Most 300b amps have 7 watts output or so. Is your amp an SET (and therefore class A2) or is it push-pull?

If an SET, it is essential that the speaker have higher efficiency. I am running a 30-watt amp on speakers that are 98 db, in an average size room (17x23') and that seems to be about the minimum amount of power to get by. With SETs in particular (my amp is an OTL) you don't want to be driving the amp hard if you really want to hear what it can do (which will be good low level detail/transparency). That will require a speaker that is 98 db at the minimum, 103 would be nearly unlimited headroom.

That is why you see so many SET users using horns.

Plan B- if you really are considering a choice between these two speakers (both are excellent- FWIW I prefer the Ref3a in this case), then you will want to get a more powerful amp- one that has at least 100 watts. The 10 db difference in efficiency of speakers (91 to 101 db) translates into a 10X power difference.
Agree with the posters saying you need 98dB efficiency at a minimum for that type of amp, especially if it is single-ended, in which case you will want even more efficiency if you are in a large room. Horns match very well, as others have said. You certainly don't need to spend 4-6K, either, if you don't want to - I got a very nice pair of Klipsch Cornwalls on this site for only $600. You may need to spend a little more than that, but certainly not 4-6K. Anything in the Klipsch Heritage series would be good, or something similar.
I run a pair of 300b 8 watts SET with Coincident Triumphs Extremes and two passive subs with wonderful results filling a room 20x23x9
94db@1meter but most important a flat impedance curve of 8ohms
Actually, my power amp have two 300B tubes in each channel.

Rated Power Output: 24 Watts RMS
Input Sensitivity: 0.33 Volts for full output
Input Impedance: 100,000 Ohms

Since I don't listen music very loud, do you guys think 24W is good enough for Grand Veena? I love female vocal and Jazz music.
I was consider Avantgarde speaker, however, my place is little bit too small Avantgarde speaker even the smallest model.
do you guys think 24W is good enough for Grand Veena?
Actually, no. About 100W is more like it. Regards
One of the great ironies/mysteries of life is that one usually needs more power to get full-range sound in a small room than in a big room ("but it's a bigger room so needs a bigger amp!" he said). To get full-range efficient speakers, one is usually dealing with a large box which may require more distance. Small bookshelf speakers require more power to drive well. Such, to the everlasting chagrin of horn-loving studio apartment dwellers, is life. As Johnk mentioned, the Model 15 does a decent job (though noone would ever accuse it of being a 'big-boned' bookshelf speaker), and depending on your tolerance for tall speakers, something like a Cain & Cain Abby might also work - again... I recommend a dig through the archives.

Off my experience with the 15ish watt Cary monos and the deCapos, I'd tend to disagree with the general theme here.

If you don't listen loud and you're in a small room and your program material contains little deep bass (and from your last post, all of that sounds true), I'd suspect that you'll be fine with your amp and the 3a speaker. OTOH, if your jazz collection is long on Jimmy Smith, you might want to reconsider.

This is just MHO, and it's based on a different - but related - hardware combo, but I doubt you're NEED more grunt for the 3a speakers. It probably wouldn't hurt to have it, though.

MSRP on the Reference 3A Grand Veena is $8k, and on the Focal it's $11k. So if you say $4k - $6k I assume you're looking for a used pair.

While I agree that in a smaller room, with the right sorts of music, 24W might be enough for those speakers (but see note below), there are others you could consider that are higher efficiency and might give you more options in music. A few easy examples would be the Zu Audio Druid (101dB, 12-ohm impedance, $3500 MSRP) and the Emerald Physics CS3 (95dB, 8 ohms nominal, MSRP $3k).

There's more to the equation than just RMS watts and sensitivity. In particular, both the Reference and the Focal drop to around 4-ohm impedances somewhere in their curves, and this means your amp has to supply the corresponding current (or live with the dynamic limitation). This is where solid-state is usually better than tubes.

IMO the Druid is a much nicer match to your amp than the speakers mentioned, as its higher sensitity and higher impedance will make much smaller demands on the amp. That is not to say that those speakers can't work, just that they don't seem to be particularly well-mated.