Fidelity Research FR-64 vs. FR-54

Dear @lewm : Not a monster that's for sure. The ML amps is a very special amp design with no trouble on handle almost anything with real aplomb.No, I don't have that nigthtmare impedance curve you name it, ADS makes no that kind of " mistakes ".

Yes, the best resistor/cap/inductor or cable is NO resistor/cap/inductor or cable but sometimes as it happens in the 99% of the speakers designs are need it. I think that the passive crossover in my ADS is optimized and does the less harm to the audio signal you, me or any one else could achieve. So, I'm confident on this main issue.

In the other side and when you are talking of " linearity " we have to think that today transistors designed expressely for audio are not the same as in the " old " times and other than that we have to talk here not only on linearity but about frequency bandwindth, signal transfer velocities, intrinsic devices distortions and the like.You are a wise man, so don't try to justify what in 2017 has no single justification other that you already pay for it and have to live with. Remember that like me you are a " by product " of that touted AHEE and this is your problem not mine.

Btw, I'm not the only one that sees the light but a person that sees the light in way better way that some as you can't do it yet.

In other thread you posted that have some bass problems with your main system and you want to solve it adding subs and I know that move/action it helps but as you stated somewhere tubes are not for bass overall management.

I know very well your Sl and heard it with tubes and ss electronics and differences are like nigth and day. Yes, I know you like tubes and you said I'm with ss alternative but the reality is that I like MUSIC not electronics.

Regards and enjoy the music,
R.

Dear @thekong :  """  I hope you ........ wouldn't mind doing the following simple test and let us know what happens.............................................................
......................................................................
I doubt that you could have complete silence (or faint noise from the phono) at the headphone. I am pretty sure you could hear faint music through it (although it could sound funny as it has gone through the RIAA stage). """


Makes no sense to me that you ask for some tests in my audio system when I have to prove you or any one else nothing at all. I already told you here and evrywhere in other threads why I can have a quality sound reproduction through my home audio system that you can't have it and because you can't have it you just can't imagine or understand what I'm talking about.

""" I suppose if you play the Telarc 1812 at 109db peak, you probably could feel the pressure on your chest. """

that stament you made it confirm you understand it because in my today enviroment I don't feel the pressure in my chest ! ! !

Do it a big favor and maybe the best in your audio life: 

- avoid any single tube in the audio signal. Yes you have to change to SS.
- install a dedicated fully regulated  power electrical line with surge protection, 80-90 db noise reduction and RFI/EMI supresors.
- that all your audio system eletrical power cords be connected/soldered with pure all silver cable directly to the electronics boards with no single connector in between.
- by-pass all fuses in your audio system.
- install two well designed active subwoofers in true stereo fashion in your system. With the main speakers working as a satellite ones and with out external active high pass crossover.
- reduce at minimum the room treatment.
- that your phono stage comes with the Neumann pole at the RIAA eq.


WShen you did it then run the tests you are suggesting that I do and after that come back to me and the forum to share your experiences.

I never ask somebody something that I did not experienced my self in my system and never talk about theories but facts, first hands experiences: always.

Yes, as many of us ( including me. ) you have to learn many things.

Test your self is the " best " way to grow-up to any audiophile.

It's very easy to give opinions that if not experienced are useless for you, me and everyone. You can't understand of what kind of distortions I'm talking about because you never been aware/detect it, you just don't know exist and have plenty of them in your today set-up.

In the other side, I have three finished of our self tonearmdesign and of course that I can't ask you have it because this you can't do it: yet ! ! ! 


Regards and enjoy the MUSIC not DISTORTIONS,
R.

I am a bit embarrassed and apologetic to the others as regards this exchange of insults in which I have participated. Fleib, your tone is no surprise to me; cut back on the coffee. Your level of certainty based on no data is also not a surprise. Raul, let’s just get one thing straight, if nothing else: you have never heard my Sound Lab speakers or any Sound Lab speakers that have been dramatically altered as have mine. My speakers have essentially no crossover, whereas the OEM Sound Lab speakers have an RC network to produce a high pass filter. The filter causes a major impedance dip at midrange frequencies. Furthermore, the resistor in the RC network robs amplifier power (Fleib). This robs the speaker of dynamics (Fleib), even when driven by a solid state behemoth, and really kills it with tube amplification. Please grant me this one thing, as I am willing to grant you that I have not heard your specially prepared and set up ADC speakers. If you want more info on the Sound Lab mod, we wrote about it on the Sound Lab Owners Group website. Dr. West modified his production speakers after thinking about what we had done, and why we did it, although he did not take our ideas as far as we did. ("We" is a guy in Australia and me, and then several other SL owners.) I found Dr. West to be a very fine gentleman. By the way, I would never use a transformer-coupled tube amplifier to drive ESLs. I use OTL tube amplifiers only, and my amplifiers are also one of a kind. I think when Raul dismisses tube amplification, he is really thinking about the imperfections of audio output transformers. My whole system upstream from the ESL has two capacitors in the signal path, one is 0.1uF and the other is 0.22uF (excluding the RIAA network of course). Both caps are teflon film and foil (VCap CuTf). Anyone who lives in my area is more than welcome to stop by for a listen, except Fleib.

Neither of us probably has any idea what the other is listening to. But, of course, I have two separate audio systems. The other one is based on a Beveridge 2SW with transmission line woofer below 80 Hz. The Beveridge is a direct-drive type of ESL in which the back wave is completely attenuated and the output from the front of the panel is refracted by a wave guide. NO audio step up transformer, no crossover above 80 Hz. (At 80 Hz, I use an active crossover with premium parts.) The Beveridge is quite dynamic (Fleib). Not the technicolor dynamics of a typical horn speaker, but definitely fast. The input and drive sections of the Beveridge direct-drive amplifier are solid state. Tubes are required in the output stage to achieve the +/-1600V needed to direct-drive the panels. (The FR64S is in this system.)

I promise that this is my last retaliatory post on this thread, and I do apologize to others for the sturm und drang. Now I think I will relax and enjoy the music.

Great post Lew. You may likely already know this, but Roger Modjeski, the designer of the direct-coupled amp used in the Beveridge, is now making his own direct-coupled ESL at Music Reference, with a sub for the bottom two octaves. I'm dying to hear it!

bdp, Inside the chassis of each of my Beveridge amplifiers is the inscription, done in magic marker: "RM 1979".  Knowing that Modjeski collaborated with Harold Beveridge back then, I have always assumed that he is "RM".  With the help of an EE who owns a pair of Model 2 speakers, I/we have made quite a few improvements to the circuit, but there is only so much you can do, because the input stage is amazingly complex to begin with and for good reasons.  He usually sends me long and detailed email instructions, and I print them out to have them at hand before doing anything new or trouble-shooting.  I zapped my finger-tip once with 1600V; you don't forget that experience.  When the speaker is fully assembled, the panels sit directly on top of the amplifier providing a direct connection between the two. The amplifier section effectively is the base of the speaker, for each channel. No loose speaker wires allowed.  I bought a copy of the schematic from RM, a few years ago when I first acquired the Bevs.

There's at least one company (in Europe) that markets a ESL direct-drive amplifier which they claim can drive the Sound Labs, which is no mean feat, since the SLs require at least 5kV on each stator (and no one outside of the SL factory really knows exactly what the voltage needs to be).  Ralph Karsten says he can make one, too. I am tempted. Maybe in my idle retirement years I will try it.