Where should I go next? Where are my weak links?

Syntax, why is the Lamm better than the Steelhead?

Believe me, deep in your heart, you don't want to know it really.... :-)

Some further comments on the amplifier-to-speaker impedance compatibility issue:

It can be calculated that the interaction of the speaker's impedance dip to about 4 ohms at 20 kHz and the amplifier's 2 ohm output impedance will result in a frequency response rolloff of about 3.5 db at 20 KHz. The impedance dip to about 8.5 ohms in the area of 250 Hz will result in a frequency response dip of less than 1.8 db.

Neither number seems to me to be all that large. Furthermore, it seems very conceivable that the speaker was voiced with tube amps in mind, which would mean that its design may anticipate and compensate for those impedance interactions. Note in Figure 5 of JA's measurements, which shows nearfield anechoic frequency response, that the response is shelved upwards by about 3 db in the 10 to 20 kHz region!

The review noted much larger frequency response deviations due to interaction with the output impedance of the Shindo Haut-Brion amplifier they were using. My guess is that the output impedance of that amp is considerably higher than 2 ohms. The review indicated that the Shindo provided only a single output tap, which was nominally rated for use with 16 ohm speakers. That would seem consistent with it having a significantly higher output impedance than most tube amps provide.

Regards,
-- Al

Dear Iramirez: Just imagine a well designed amp that you like its quality performance level and that at the same time was/is accurate/neutral to help listen what is in the recording with low low colorations and distortions.

I think that till you or any one else can have that experiences you or any one else can't even imagine or dream the pleasure and enjoy level all we can achieve through an audio system hering music.

My take is that is better try ( at least try. ) to grow up than stay in the deep " hole " majority of us are for so many years.

I'm only saying: try, learn and move on.

Regards and enjoy the music,
R.

Thanks Al for clearing up Raul's misunderstanding in this matter.

Dear Al: I'm not talking about overall speaker behavior but about a mistmatch between the Manley and the Zu due to the Manley " behavior " that due to the amplifier characteristics in true works more like an equalizer with gain that as an amplifier with the right performance to handle the Zu speakers this is the main subject.

++++ " would mean that its design may anticipate and compensate for those impedance interactions " ++++

I hope not because that means more signal manipulation that means signal further degradation.

Now, I can't see clear which your point. Are you trying to say that the Manley is a right amp for those speakers? or are you trying to diminish the impedance mistmatch between Manley and Zu? which your point?

As I posted : why any one of us could try to diminsh or ignore the critical importance that have a matching or un-matching amplifier/speaker combination on system quality level performance when any one of us take care matching cartridge impedance with phono load impedance or tonearm/cartridge match combination to achieve better quality performance level?

which the difference when maybe the speaker/amplifier impedance matching can be more critical and sensitive than the others?, makes no sense to me.

Trying to match electrical impedances between any other audio links but the amplifier/speakers always is important an almost all of us take care about: I repeat, which the difference with the amplifier/speaker impedanmce matching? why almost all do not care about? which is the explanation behind this audiophile behavior other than ignorance?

Which your take ?, I ask you because you know what we are talking about and I can't see you agree with that critical Ohm's Law importance. Again: why diminish it?

regards and enjoy the music,
R.