Purity vs. Prodigy

[Stereonerd]

Hi Martin Logan fanatics. Is there someone out there who is qualified to give me advice on Purity vs. Prodigy?
I've owned a pair of Purity speakers since 2010, and love them to death. They never fail to give me pleasure.
But of course, I always think: maybe I could do better. And the thing is, I think the internal power amplifiers let them down a little. There's a 'glare' in certain frequencies that I don't get when I connect speaker wire and use my Perreaux amplifier.
So I'm thinking: maybe a pair of MLs without the internal amp would be preferable, as it seems the Purity was a one-off experiment. In theory, powered speakers are great, but they are kind of inflexible if you want to try out different amplifiers.
It's hard to find MLs in NZ, but there's a pair of Prodigy's for sale second-hand locally, and I'm wondering whether they would be a step-up from the Purity's. Or because they're a generation or two earlier than the Purity's, would I be going backwards in terms of sound quality?
Any advice? Thanks!
Gary

 

[Rich]

This is kind of comparing apples to oranges. The Prodigy was the top of the line speaker of its era. They are huge and massive, with two big woofers and a wide panel. They sound incredible if driven with enough power. But they do take up some room. The Purity is one of the lower end models of its era. It is smaller and lighter, with a smaller panel and small woofers. The Purity has about 240 sq. inches of panel area vs. about 750 on the Prodigy. Purity has a crossover at 450 hz. vs. 240 hz for the Prodigy. In short, the Prodigy will go much deeper, put out more volume without distortion, put out a more convincing soundstage, and a lot more. But it is a whole lot bigger and imposing. And if it is not in excellent condition the panels could need replacing at some point in the near future, which could be very expensive.

Edit: I think the Prodigy is one of the best speakers ML ever made. But you really need a room big enough for them and equipment capable of driving them to get the best out of them. The Purity, on the other hand, is kind of a lightweight. It can sound good in a small room at lower volumes, but it can't begin to compete with the Prodigy when pushed.

 

[twich54]

Gary, I believe Rich nailed it !

 

[edwinr]

The Purity is a great speaker. But the Prodigy is one of the best speakers Martin Logan ever made. Just be prepared to spend more on the rest of your system to keep up with the Prodigies.

P.S Is the plural of Prodigy, Prodigies or Prodigy's?

I think Prodigy's has possessive connotations.

 

[Stereonerd]

Thanks for the advice, gentlemen. I hadn't realised that the Prodigy was quite as elevated in the ML lineup. I have always aspired towards a Summit, but perhaps the Prodigy is similarly great?
I've found that the Purity does amazing things for its price point. In fact, I run a hi-fi oriented website in New Zealand (I'm the editor - I have correspondents with a great deal more technical hi-fi knowledge than me) and in my time there have heard lots of expensive speakers, many of which are worth three or four times what the Purity is worth, but don't sound as good. I guess that's the ML/electrostatic thing - the inconceivably wide, accurate soundstage/stereo image.

Two more questions, if anyone cares to answer them: What would be the minimum power amplify that the Prodigy would require? And what would be the minimum room size for the Prodigy to sound good in?

 

[edwinr]

I run my Montis speakers in a room about 6 metres x 5.5 metres in size. That's pretty much as small as I'd like to go because my room is of double brick construction with no room treatments other than some furniture and curtains. The Prodigy would need a room at least as big to sound it's best without some room treatments.

Martin Logan's later designs (which feature powered and tuneable bass modules) are easier to tune for difficult rooms. The Prodigy would need a little more care, but the results should be well worth it. And yes, the Prodigy is a truly great loudspeaker.

 

[Nutshell]

There's a 'glare' in certain frequencies that I don't get when I connect speaker wire and use my Perreaux amplifier.
Gary

do you mean here that you are switching between the RCA inputs and the speaker binding inputs of the Purity's? In both cases, you are still using the internal amp of the speakers. Just like with the ML's that only have a powered woofer, you can connect the Purity's to an external amp and still use the internal class D.

 

[Stereonerd]

Hi Nutshell,
I know that there is technically no way of bypassing the internal class D amp on the Purity's, but there sure is a HUGELY different sound when I use the speaker binding inputs to feed in another amp. I have no idea how this works, but it sure does mimic the characteristics of the amp I'm using. Is it a BLEND of the class D in the powered speakers and the external amp, or something else? It's a mystery to me!

 

[Nutshell]

My amp isn't very sophisticated, though not bad, but my dealer also recommended to use the speaker posts in stead of the RCA inputs for this very reason. I have always done that since, because I didn't want to invest in expensive long interlinks that won't be useful anymore in case I buy new speakers.

 

[roberto]

Hola. It is the same circuit topology that is being used at car stereo since long time ago. You feed the power amplifier of the Purity with your amplifier speaker´s cables out put. It is a very high impedance input circuit, so your amplifier is only feeding the signal and this Purities input circuit, does not represent any load to your amp. This impedance circa over 3.K ohms. Your amp reads it as an open circuit. Your amplifier will not read any load. You use your amp as signal feeder only. Happy listening!