Classic French speakers worth having?

Aren't these Neurochrome amps supposed to be really good into low impedance loads?

I suspect the dealer seeing the opportunity to flog a power amp too.

It's not just the sensitivity you need to check when looking to amp match to a speaker, it's the minimum impedance, where this occurs in the frequency band, and whether there are any significant phase swings which would demand large swings in voltage. E.G. Factory (I use that term VERY loosely) Impulse H2's have a rated sensitivity of 98dB/1w/1m.

Sounds like an easy load, right?

They have a minimum impedance dip averaging over all pairs I have tested at 2.8 Ohms between 700Hz and 1.2KHz, so where a not insignificant current demand lays. Furthermore, their stated or claimed sensitivity applies sneakily to the mid horn and nowhere else. Equalised to the bass output, their true sensitivity once corrected is closer to 88dB/1w/1m. Not looking very rosy now for the flea powered amps that some torture trying to drive these things and is the reason why so many claim a "hardness" or "harshness" in the mids. It's because their amps are clipping trying to drive these "98dB" speakers! That and a mid horn so lifted (10dB in free space) that it shouts at you in anything other than low level "girl with a guitar" type music. Not such an easy load after all.

Many speakers are the same. Their stated nominal load tends to be where the bass is low and phase angle swings. The actual impedance profile can be like the alps on some models and the phase angle if too steep and too high in magnitude (say anything much over 45 degrees) just too much for under powered amps or amps with poor power supply reserves to deal with.

I never understood, nor still don't why most manufacturers don't or wont publish their 'speaker's impedance curves and phase angles.  It's really essential stuff when your amp may be borderline and a decision needs to be made.  I provide this information for all speakers that come through here and of course for any of my own designs.  It's basic stuff and should be provided.

That'll likely be between bass and mid frequency in the crossover region

This is typical of the reviews I have found - link
I am really quite interested in these. They will be easier to sell over here,  if I decide to move them on at some point.
I just hope that this virus malarkey ends soon, so I can go and have a listen with my amplification.

I figure that the amp should be good enough with the volume I listen at in my room. I may need a bigger amp when I retire, but I have a lot of time before that happens.... 

Try and get a listen to JM Labs Mezzo Utopia.

My brother sold his for £1800 5 years ago, they were 10/11 years old. It must be 15 years since they stopped that particular model, my guess would be new price then £8500 so they are well overpriced in my opinion. It took a pair of Estelon XB's to oust them from his system, they were that good.
Just checked JM Labs launched their beryllium tweeter in 2002, the Mezzo did not have that, and they launched the replacement Alto Utopia be 2003.

1999 - $13000 dollar

Allow for inflation that's 26,000 big ones.

So $5500 dollars today for a second hand set - it's not ridiculous. 

If you like their detailed and forward sound then Focal's are exceptional. I didn't get on with mine because I prefer a slightly less up-front sound, but I can't take away how good they were.

I converted the euro price into dollars for the purpose of comparison.

I was just pointing out that if made today that would be the price in today's money - maybe knock a bit off as you are right, they would have been more expensive in the States than in Europe - so gives you some idea of what market tier they were in. Have to say I was surprised, if asked to guess I'd have said they originally cost half what they actually did.

There's no rules here - if someone comes along and pays him 5000 euros for them then that's what their worth. If no-one does then they must be worth less.

Based on my own observations of the second-hand market I'd say *in general* that people asking more than 50% of the new price either take ages to get a sale or don't get a sale. Not just with speakers, with any item. So as soon as you drive it out the showroom it's down by half. Needless to say I rarely buy new.

The problem with old speakers is the condion of the crossovers and drive unit surrounds etc.

Have a look and a listen before you pay.