help choosing speakers again >90dB wanted

[Ap]

Actually a 6.5" MTM floorstander would be ideal - something like the Living Voice Avatar. Even might be worth having a look at the Proteus (do a search on it).

[Mike C]

I have similar requirements and posted a few weeks ago.
Here's some comments.
First, my room is very similar size (18ft x 14ft). Current speakers are IPL smallish trans lines, single 6.5 inch bass driver, about 88dB.
I have no trouble getting all the volume I need from a 6.5 watt 300B SET, with some in hand.
Of amps I've used, in increasing quality: Naim NAP140 (50wpc), Assemblage st40 EL34 PP (45wpc), same trioded (22wpc, small but very useful improvement), DIY 300B SET (6.5 wpc). Kind of says something about correlation of power to sound quality!

Now I'm not into rock etc so I like bass that plays natural notes naturally; someone into strong rhythmic rock may prefer more bass impact and stronger control I guess; but accoustic music sounds very good.

Anyway I think you'll find say 91dB or so quite enough, and losing a few dB compared to the present speakers to get higher quality and better bass should be a good trade off.

I'm looking at Zaph's large MTM (XG18 and SEAS 27tdfc) as it's an excellent speaker and seems to meet the needs.
Myself, I may use the XT18 (WH version), as it has slightly lower Vas and 1dB more sensitivity. The latter just needs a slight tweak to the tweeter series R.
The impedance is of course somewhat low but seems fairly constant - should be OK for the SET. I'll go for the reflex ported floor stander myself as I think it will give the bass I like - not excessive but tuneful and reasonably low.

I think similar could suit you very well.

Another possible is RZ Audio's RZ6:

http://www.rzaudio.com/rz52/rz6.htm

Seems a simple but very good speaker (nice engineering!). Uses a fairly high sensitivity driver that seems to suffer less breakup than most high efficiency ones. Should give 88dB - about what I have, less than we might want; but it's a nominal 8 ohm speaker. n my case I'm tempted to consider a TL version of it, as I seem to find that my SET likes a TL .....

And the Troels and Humble sites offer some other interesting MTMs and a TL that might suit us ...
so many projects, so little time!

I'm sure all are excellent. Oh, I've driven several speakers with my SET as tests and in every case I've had excellent sound, even with low sensitivity JR149's so I would not worry over much about your valve amp. In choosing a speaker, don't compromise sound quality for the ultimate in sensitivity, I'd suggest.

[kmj]

And the Troels and Humble sites offer some other interesting MTMs and a TL that might suit us ...
so many projects, so little time!

I'm sure all are excellent. Oh, I've driven several speakers with my SET as tests and in every case I've had excellent sound, even with low sensitivity JR149's so I would not worry over much about your valve amp. In choosing a speaker, don't compromise sound quality for the ultimate in sensitivity, I'd suggest.

I have checked most of those sites and the choises are Zaphs MTM as you recommended, Troels C17 which is supposed to work quite well as long as you don't play to loud and the Auriga from Humble hommade hifi. The initial idéa was to make this a long running project and by doing that allowing a higher budget and having more time to make a really nice cabinet but when I see the less expensive drivers of the C17 I am tempted to just go with them.

The most optimal would be a set of speakers with up to date drivers that wont dissapear from the market in the next few years, not to expensive (not as important) and using 10uF capacitors in the crossover since I have some Leclanché paper-in-oil-caps with that value and those are suppost to be something extraordinary..

[pjpoes]

I think consistency has been lack luster at best in the past, but Tang Band has a 6.5" driver w6-789S which has 92db effeciency itself and decent overall specs. In an MTM configuration with the right crossover, say a series crossover as I think they have less loss, I believe you could get a speaker with around 95 db's effeciency. It would have to be matched with a very effecient tweeter, possibly a horn loaded dome such as the one Zaph uses in a project, or possibly just a premade one. I bought a 4 of these drivers to begin playing with, so far they don't measure alike, which isn't great, but I think they are close enough to make a set of speakers with, I just might need to adjust crossover values.

They are much more expensive, and I have no idea if you could get the effeciency you want, but I am really in love with the ScanSpeak slit cone drivers in general. I have now built two pairs of speakers using them, and the bass was among the best I have ever heard from small speakers. Every speaker I have heard using these drivers generally sound superb, and I'm yet to use another driver I really like much better. The seas are very nice too, better midrange maybe, but the bass isn't as good. I really would like to build myself a set of MTM Towers with a transmission line cabinet and those Midbass drivers. I think they could be a great speaker for me. Their ability to handle macrodynamics is superb.

[inrank]

mabye slightly not - as diy as you wanted but what about some 10-12" HPD Tannoys? if you dont mind larger enclosures (30L of the 10" and 42-64L for the 12"'s) will (in my experience) give you a dynamic and fun sound thats quite forgiving.....

just my 2 pence

[imperfectcircle]

Well I understand where your coming from, I once had a similar low power tube + single driver speaker setup as you and it sounded great with lighter stuff, but pretty bad on metal or hardrock. I think the c17 is a good idea, but I think something along the lines of his 3-way classic may even be better. Rock just sounds awesome through 3-ways for some reason. I'm not sure why that is but the best speakers ive heard with metal and rock have always been a basic high efficiency 3-way like some of the older Jbl or Klipsch designs(heresy, cornwall). I found this design while surfing the net big 3-way maybe something in between Troels small three way and these monsters would be perfect? good luck and happy listening!

[kmj]

imperfectcircle
Those big ones were REALLY huge, perhaps something for my friend to pair up with his Krellklone

And I'll check the classics a bit more even if they seem to be a bit too imposing for my taste. Thanks for you opinions/pointers

[imperfectcircle]

These are cheap, easy to build and made for low power tubes.
Decware 3-way