Using tube amp with electrostatic speakers.


Moons ago I started similar discussions and thought I had been given enough good advice not to approach the subject again. Here goes anyway. I've used Martin Logan electrostats for well over 30 years with quite a few different amps but have recently switched to a tube amp and dynamic speakers with which I am very satisfied.  It consists of the Cary Rocket 88R amp and Serie Reference 3 speakers. 

My brother was visiting last week and was so impressed with the sound that he decided that he might want to try a tube amp also (probably the same one as mine).  However, he is using a pair of SL3's that I gave him years ago and I'm concerned primarily about the current requirements of the Martin Logans as well as other concerns that I'm not thinking of.  I don't want him spending money on something that may not bring him improved sound so would appreciate more advice to pass on to him.  He currently uses a Rogue Audio SS amp with his SL3 speakers and, to me, it sounds very good. 
jimbreit
What occurs to the sound of the speaker when the transformer saturates or begins to saturate? Is transformer saturation a voltage or current issue?
Distortion- Its pretty obvious. Its a power issue- both current and voltage (of which neither can exist without the other).

Are you saying:
1. That the resistor is not needed for either the Toroid l or Toroid ll?
Not needed for the Toroid 1, needed for Toroid II

2. That the concern of transformer saturation does not occur (at higher input signals) because:
    a) at higher frequencies the music power requirements are typically not high (so the Toroid will not/does not saturate); and    
    b) the Toroid impedance increases at lower frequencies to a level that the Toroid cannot saturate even with a higher voltage signal (in other words the Toroid by it's impedance nature is self-limiting to prevent saturation?).

We're talking here mainly about the Toroid 1:

Bass energy can saturate the core of the part, because it was built with intention to optimize higher frequency performance. In practice it does not saturate with low frequency energy simply because its impedance is so high at lower frequencies (and there is a capacitor in series with its input) that most amps can't make any power at those impedances.

The Toroid II:

The crossover of the resistor and capacitor prevent lows from entering the input of the transformer; otherwise it too would saturate because its core is too small just like the Toroid 1.

HELP?

In your opinions, would a pair of Balanced Audio Technology (BAT) Rex II mono blocks be powerful enough to make the Martin Logan Neoliths sing?

I'm currently using a pair of Krell 575 mono blocks, which is powerful enough, but I'd like a warmer sound with more harmonics. I mostly listen to old standard jazz LPs from 50's to 70's (at night club sound level) and smooth jazz CDs (at concert levels).

BAT: 

 

Neolith: 

 

Dear  @milt808  : " a warmer sound with more harmonics. "

 

First the harmonics are developed by the recording source we are listening it and those harmonics have changes through all the signal path where that signal must travels in our room/system till goes in our ears/brain/body. A good room treatment and fine tunning the subwoofers SPLs can help for that warmer sound  you are looking for that again depends on the signal source. The issue is not about tube amplifier because your speakers impedance at a critical 20khz frequency is down to 0.43 ohms and I don't know yet a tube amp that can handled with applomb that speaker impedance.

In my opinion this is the amp for your system and I think you can't go wrong with:

 

https://parasound.com/jc1+.php

 

Regards and enjoy the MUSIC NOT DISTORTIONS,

R.

Unless Martin Logan  says otherwise, I would assume that they have not abandoned their stated policy of designing their speakers to accommodate solid-state amplification best of all. That really means the speakers are likely to have a low nominal impedance. You might check this out with Martin Logan. If I am correct, then you may be best off with a solid-state amplifier, but there certainly is no harm in trying those BAT amplifiers, if you have them on hand. If Raul is correct about the impedance at 20 kHz, that squeaky low impedance could be vexatious for any amplifier, solid-state or tube type. However, the saving grace is that very little amplifier power is needed at such very high frequencies.