Alexx V arrive in NJ

[KeithR]

I think Marty just likes the slam factor of the JC1+ better, which is a trait that its been always known for. I do think a low negative feedback amplifier and Wilson may not be as good a technical match though (and recently heard the Dart 108 on Wilson Alexx V).

If you'd like more midrange palpability than the JC1 in the interim for a base amp, I'd try Ampzillas which are inexpensive used. They have tremendous bass as well.

 

[Ron Resnick]

Gryphon Mephisto has no negative feedback and an iron grip on the woofers.

+1

And I think it's one of those rare products about which even Sherlock Holmes himself would have trouble finding a critical word.

 

[Carlos269]

+1

And I think it's one of those rare products about which even Sherlock Holmes himself would have trouble finding a critical word.

The Gryphon Mephisto Solo suggestion for Marty is a very good suggestion as the Gryphon Mephisto Solo amplifiers have an output impedance of < 0,013 Ohm.

I own the most powerful amplifier that Gryphon Audio has ever created. One that most have never heard, as it is very rare, and that is the Gryphon Encore.. The Gryphon Encore is rated at 500 Watts per channel and has an output impedance of 0.055 Ohms. It will drive the Alex V, or any other speaker, without issues.

There are other well designed amplifiers that will provide the bass slam and control, that Marty desires, along with the organic sound on top. The key is not to limit oneself to components on the equipment recommended lists in publications or to flavor-of-the-month components.

 

[KeithR]

+1

And I think it's one of those rare products about which even Sherlock Holmes himself would have trouble finding a critical word.

you'd be surprised from what i've heard in my amp research

 

[Ron Resnick]

you'd be surprised from what i've heard in my amp research

I would indeed be surprised!

 

[gian60]

My friend has A1 mono,was mine before i took M1 mono,with Wilson Alexandria and seems perfect match.
Before had Krell Evo One,Viva New Aurora and tried at home Dan D' Agostino mono,but his bass was always too much,and cannot control very well,with A1 is very good,clean fast,deep and controlled.

 

[gian60]

And with 0 negative feedback

 

[andromedaaudio]

And with 0 negative feedback

That may very well be , as it is a very easy load

 

[LL21]

I recall the original Alexx was quite a difficult load...from STereophile below:

Wilson Audio Specialties Alexx loudspeaker Measurements

Sidebar 3: Measurements Because this speaker's size and 452-lb weight made shipping one of them to me for measurement impossible, I drove my test gear to Michael Fremer's place. I used DRA Labs' MLSSA system and a calibrated DPA 4006 microphone to measure the Wilson Audio Alexx's frequency...

www.stereophile.com

"...Although Wilson's specification is correct, in that the minimum magnitude (solid trace) is 1.5 ohms just below 3kHz—I measured 1.44 ohms at 2.9kHz—the impedance remains at or below 3 ohms from 55Hz to 6kHz, and the electrical phase angle (dotted trace) exacerbated the drive difficulty in some regions of the audioband. The combination of 3 ohms magnitude and a phase angle of –44° between 56 and 59Hz will stress amplifiers, as will the combination of 2.2–2.6 ohms and a phase angle of +40° between 4 and 5kHz. Alexx owners need to match the speakers with amplifiers unfazed by very low impedances."

I think the new Alexx V may be less so but still appears to be 2 ohms at 250hz...also from Stereophile measurements:

Wilson Audio Specialties Alexx V loudspeaker Measurements

Sidebar 3: Measurements Because of the Alexx V's size and bulk, I measured its performance in Jim Austin's listening room. I used DRA Labs' MLSSA system and a calibrated DPA 4006 microphone to measure the Wilson Audio Alexx V's frequency response in the farfield, an Earthworks QTC-40 microphone...

www.stereophile.com

"...My impedance measurement is shown in fig.1. The impedance magnitude (solid trace) remains between 2 and 4 ohms for almost the entire audioband, with a minimum value of 1.9 ohms between 242Hz and 270Hz. The electrical phase angle (dotted trace) is low from the upper bass to the low treble, but there is a combination of 3 ohms magnitude and a phase angle of –39° at 53Hz that exacerbate the drive difficulty.

Using a spreadsheet prepared by Jim Austin, I calculated the effective resistance across the audioband (EPDR, footnote 1) that results from the combination of magnitude and phase angle. The EPDR drops below 2 ohms over most of the midrange and mid-treble regions, with minimum values of 1 ohm between 50Hz and 64Hz, 1.15 ohms between 197Hz and 203Hz, and 1.05 ohms between 3kHz and 3.16kHz. Owners of the Alexx V need to match the speakers with amplifiers that are unfazed by very low impedances."


Based on my own limited experience...seems like a job for Gyphon as a few have noted. It doubles all the way down to 0.5ohms and doubles again all the way down to 0.5ohms in peak. So for Mephisto monos, that is something like 6400 watts peak into a 0.5ohm load.

 

[microstrip]

It is great to speculate without even having proper data, but we should also consider that most of the time Wilson Audio uses the D'Agostino Momentum's and the VTL Siegfried II in their room and these amplifiers have a damping factor of 35 and less than 10, respectively.

I hosted the Momentum's with the Sonus Faber Aida's and they had fantastic bass weight and control. It is known to be one of successful matches with Wilson Audio low impedance loads and bass sound quality.

After reading Martin Colloms comparative review of the Krell FBP600 versus the Cary 805 single end amplifier in the early 90's, where he reported that fitting a resistor having the output impedance of of the 805 in series with the FPB600 did not make it sound like the single ended amplifier, I got a few power resistors of high power and high quality and did my own experiences. No way I could tune my high damping amplifiers to a "better" sounding one just adding resistors.

Matching a component in an high-end system is not an entirely predictable experience - it needs a lot of experience and good knowledge of the owner preferences, as well as of room characteristics. Surely we can rule out all the nice things we enjoy in our hobby and reduce our experience to an average stereo sound reproduction.

 

[Carlos269]

It is great to speculate without even having proper data, but we should also consider that most of the time Wilson Audio uses the D'Agostino Momentum's and the VTL Siegfried II in their room and these amplifiers have a damping factor of 35 and less than 10, respectively.

I hosted the Momentum's with the Sonus Faber Aida's and they had fantastic bass weight and control. It is known to be one of successful matches with Wilson Audio low impedance loads and bass sound quality.

After reading Martin Colloms comparative review of the Krell FBP600 versus the Cary 805 single end amplifier in the early 90's, where he reported that fitting a resistor having the output impedance of of the 805 in series with the FPB600 did not make it sound like the single ended amplifier, I got a few power resistors of high power and high quality and did my own experiences. No way I could tune my high damping amplifiers to a "better" sounding one just adding resistors.

Matching a component in an high-end system is not an entirely predictable experience - it needs a lot of experience and good knowledge of the owner preferences, as well as of room characteristics. Surely we can rule out all the nice things we enjoy in our hobby and reduce our experience to an average stereo sound reproduction.

Damping factor is a logical explanation of the situation to this degreed electrical engineer. What says you is the cause of Marty’s experience? Or should we go back to buring our heads in the sand?

Adding a 1 Ohm resistor in series may not be a silver bullet, I simply stated that it is a worthy experiment that could mimic the CH Precision sound with the JC-1+ amplifiers and still retain a certain level of bass slam and control that could be an acceptable solution to Marty.

I‘m not sure if you realize that the your above statements about your experience with adding series resistors and the unpredictability of the high-end component matching kind of gets no one anywhere. We share our thoughts and ideas to get an explanation or bring clarity into an issue in an effort to move the situation forward. Why post the issue in the first place if the goal is to remain in the dark? We should not always resort to the “we don’t have all the data” and some times it’s okay to speculate based on our professional, or even amateur, experience.

 

[microstrip]

The discussion raises some interesting points. Some are more easily dismissed (i.e. the role of speaker wire) while others may be more relevant (the mental status of Ian and me, ha!). But one parameter that might be most relevant in sorting things is the issue of amplifier damping factor.

Damping factor is the ratio of the rated impedance of the loudspeaker to the source impedance. In solid state amplifiers, the damping factor usually has a maximum value at low frequencies. A quick read in Wikipedia is informative and provides many fine points and provides comments from such luminaries such as Toole, Atkinson and Pass. The “In Practice” section is particularly relevant. However, the one thing that is missing when considering amplifier performance comparatively is the actual reported damping factor for the JC1+ and M10 (or its relevant cousin, amplifier output impedance).

Unfortunately, I can’t seem to find it for the M10. The damping factor of the JC1+ is specified as >1200 @ 20Hz. Wouldn’t that be nice to have?

Before we bang our heads on the wall any further, I suggest this discussion come to a pause as we try to contemplate why I felt that the bass performance of the JC1+ was preferred to the M10. It just seems pointless to speculate endlessly until this information is known, unless of course, you are into head banging. (It's what audiophiles do! Saves wear and tear on the ears.)

Fortunately the audio luminaries also told us that in practice damping factors over 80 are useless, although technological interesting - in fact the first component the amplifier sees after the speaker cable ends is the bass filter coil, and only after it we find the speaker coil that generates a EMF.

In fact there is little correlation between bass control and damping, except for extreme cases.

 

[andromedaaudio]

Fortunately the audio luminaries

Are these the same " audioluminaries " that state you cant make a judgement regarding component B unless you use cable A

Basically turning the high end audio industry into some sort of maze

High end audio is easy you just have to follow( accept) certain principals .

Regarding amp choice it seems to me also based on what has been said The Gryphon memphisto solo s would probably be the best / safest bet in this case

 

[Carlos269]

Fortunately the audio luminaries also told us that in practice damping factors over 80 are useless, although technological interesting - in fact the first component the amplifier sees after the speaker cable ends is the bass filter coil, and only after it we find the speaker coil that generates a EMF.

In fact there is little correlation between bass control and damping, except for extreme cases.

 

[microstrip]

Damping factor is a logical explanation of the situation to this degreed electrical engineer. What says you is the cause of Marty’s experience? Or should we go back to buring our heads in the sand?

Adding a 1 Ohm resistor in series may not be a silver bullet, I simply stated that it is a worthy experiment that could mimic the CH Precision sound with the JC-1+ amplifiers and still retain a certain level of bass slam and control that could be an acceptable solution to Marty.

I‘m not sure if you realize that the your above statements about your experience with adding series resistors and the unpredictability of the high-end component matching kind of gets no one anywhere. We share our thoughts and ideas to get an explanation or bring clarity into an issue in an effort to move the situation forward. Why post the issue in the first place if the goal is to remain in the dark? We should not always resort to the “we don’t have all the data” and some times it’s okay to speculate based on our professional, or even amateur, experience.

No one is burying the head in the sand, just pointing that the suggestion was IMHO meaningless. No way adding a 1 ohm resistor to the JC-1+ will mimic the sound of the CH Precision sound, even with a lot of bias. And pointing that people had the opportunity to research the matter, but decided it not worth their efforts - it seems Eliot, a very experienced audiophile, did not even listen to the amplifiers in Marty system with different levels of feedback.

At some period, damping factor was mostly a marketing argument. It is still abusively interpreted many times in reviews - fortunately Stereophile just focus mainly in the frequency response variations induced by damping factor.

For example , Constellation Audio Centaur and Hercules have a similar damping factor - 160 - but the control, depth and quality of the Hercules bass is an order of magnitude better than those of the Centaur.

IMHO we should focus our debates in the directions that have some probability of being enlightening and bringing solutions. YMMV.

 

[microstrip]

Sorry, I do not go in seeing or debating internet videos.

 

[Carlos269]

IMHO we should focus our debates in the directions that have some probability of being enlightening and bringing solutions. YMMV.

Please you take the lead, and lets see where you go and take the group from here. Show us……………

 

[microstrip]

Are these the same " audioluminaries " that state you cant make a judgement regarding component B unless you use cable A

No, they are not. I was addressing engineers of the classical school ...

Basically turning the high end audio industry into some sort of maze

High-end is a maze. We have to accept it.

High end audio is easy you just have to follow( accept) certain principals .

What are those principals? Other than accepting a mentor I can't thing about an easy way to go through it.

Regarding amp choice it seems to me also based on what has been said The Gryphon memphisto solo s would probably be the best / safest bet in this case

Not IMHO, for many reasons. Just for example, why do you expect the Mephisto to sound better than the JC-1+ in his system?

 

[andromedaaudio]

Not IMHO, for many reasons. Just for example, why do you expect the Mephisto to sound better than the JC-1+ in his system?

Because of lloyds expirience among others .
Who has actual honest (no nonsense) user expirience and he has tried a lot of amps

(Look if you want my honest opinion , SS only goes so far beyond that you need tubes )
But thats not the question here .

 

[microstrip]

Please you take the lead, and lets see where you go and take the group from here. Show us……………

Please read my previous posts. I suggested measurements on the damping factor versus feedback and acoustic measurements of the system in Marty room showing the time behavior, such as waterfall, impulse or delay. Not rocket science or voodoo.