[studley]

Both these makes of speaker are said to be suitable for SET amps (90db +  and benign impedance) and both makes get outstanding reviews.  I'm curious as to how they compare.  Has anybody heard, say, the Devore 9s and  similarly priced Coincident speakers?   

[jrebman]

Hi Ian,

How much power are we talking about?  In general, sensitivity doesn't mean the whole story, same for impedance curve) -- aren't the DaVores multi-way with crossovers?  Anuy speaker with anything but a blocking cap for the tweeter is just not going to work with the real low power SET amps, at least none have to my liking so far.  I don't know anything about the coincidents either, but I suppose those are multiway, but in general seem to have more people using them with lower power SET amps.

A friend had a pair of Sonus Faber Amati Homages -- with a stated sensitivity of 94 db, and she bought a pair of Supratek Burgundy's to power them -- no good.  Then bought a pair of DeHavilland GM70s, and still no good.  I wouldn't put anything less than a 200 watt SS amp on those speakers, but then again, I'd never buy them in the first place .

So, what are you thinking about and what's the goal here?

Ramble on,

Jim

[studley]

Jim

I'm well aware that sensitivity is not the major factor when it comes to using SETs etc.  I mentioned it only  in passing, but I think you are wrong in suggesting any speaker with a crossover is too much for a low powered valve amp.  See this for the best explanation I've seen of amp/speaker compatability:

http://www.symphonysound.com/articles/tubefriendly.html

The speakers I've mentioned were designed to work well with 8 - 20 watts and by all accounts do.

So, anybody heard them both?

Rgds

Ian

[jrebman]

Ian,

I don't mean to say they won't work, but with the lower power amps -- 45s, 2a3s, SE el84s, etc. you'll lose most of the real SET magic in the crossover.  Sure they'll work, just won't sound their best.  Again, I'm talking about crossovers with multiple reactive components, efficiency matching resistors/l-pads, etc.

Also, the design of the amp will figure in heavily as not all 8 watt amps are created anywhere near equal.

-- Jim

[planet10]

Anything with a complex impedance curve (check phase as well as magnitude) is going to be less likely to play nice with a SET.

And why is this in the single driver circle?

dave

[planet10]

See this for the best explanation I've seen of amp/speaker compatability:

http://www.symphonysound.com/articles/tubefriendly.html

Note that he talks about tube-friendly, not SET friendly. The explanation is very good as far as it goes. Take the tube-friendly LS3/5A. That better be a solid 20-40 w push-pull tube amp with sufficient feedback to reduce the output impedance. With a non-feedback SET you will have FR peaks everywhere that the speaker has an impedance bump.

dave

[studley]

And why is this in the single driver circle?

dave

Because the description of this circle includes the following:

" . . .high efficiency speakers and complementary amplifiers"

Anything over about 92db is highly efficient as far as I'm concerned.

[planet10]

Because the description of this circle includes the following:

" . . .high efficiency speakers and complementary amplifiers"

"Discussion of single driver, high efficiency speakers and complementary amplifiers"

Given that there is no comma after speakers, the whole phrase would be the bit in bold -- which also corresponds with the circle title. And high efficiency is probably not needed in the description as many of the drivers we discuss aren't all that efficient (Mark Audio/Jordan)

I'm happy to answer questions but you might get more response in a circle where crossovers live...

dave

[studley]

Because the description of this circle includes the following:

" . . .high efficiency speakers and complementary amplifiers"

"Discussion of single driver, high efficiency speakers and complementary amplifiers"

Given that there is no comma after speakers, the whole phrase would be the bit in bold -- which also corresponds with the circle title. And high efficiency is probably not needed in the description as many of the drivers we discuss aren't all that efficient (Mark Audio/Jordan)

I'm happy to answer questions but you might get more response in a circle where crossovers live...

dave

I can't believe I'm getting into an argument over this but hell, I can be a pedant too when I feel like it and it seems like I do just now.

"Discussion of single driver, high efficiency speakers and complementary amplifiers"

That my friend reads as a list of three separate things.  If it is not intended to be such then it should be re-drafted.  Putting a comma after speakers would in any event be bad grammar; as would starting a sentence with "And" . . .

Another circle seems like a good idea.  Perhaps the correspondents will be less tetchy. 

[planet10]

I'm not protesting you posting here, just saying that in this circle XOs are not common, actually considered evil (it is the SINGLE driver circle after all), and you won't find the guys with the depth of knowledge here. This one is probably more appropriate "Source to the Ear: The Circle explores matching components..."

Putting a comma after speakers would in any event be bad grammar;

Good grammar says that whenever there is a list with an and in it a comma should follow every item in the list.

http://grammar.ccc.commnet.edu/grammar/commas.htm

Grammatically there are 2 items in the list in question "Discussion of single driver, high efficiency speakers and complementary amplifiers", 1/ single driver, high efficiency speakers 2/complementary amplifiers.

A SET is an amplifier that is usually very complentary with a single driver, high efficiency speaker. You are talking multiple driver, high efficiency speakers with cross-overs.

dave

[mca]

Oh brother...

[planet10]

Oh brother...

You are right... this should get moved into a more appropriate circle, and probably half the posts sent to the galatic wastebin.

dave

[planet10]

Can you point us to impedance curves for the 2 speakers in question/ What SET do you have?

dave