KeithR's "Dream Speaker" Search

213Cobra

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Your unhappy experiences with the earlier amps puzzled me .
The more I thought about it the more I suspected the problems were not the amplifiers or the speakers, but some other then unexplained problems which have now emerged with the substitution of the Ampzillas.
It may well be that you will be happy with the Ampzillas but the root problem with the mains remains and looks likely to be a continuing vulnerability if not addressed.

Having been involved in all the amp trials, I can say that the root problem was not the separate circuits AC feeds. The ARC 160M could not properly drive the YG cleanly on the "good side", and the Luxman, being a stereo amp was on the same circuit as the rest of the system. So was the REF75SE. They just didn't have enough muscle or control for the challenging YG. Further, the m2tech amps were run as monoblocks on the separate circuits and there was zero difference in performance with them, neither flashed their peak LED indicators with up to 440 w on tap, but they also don't demand a large draw from the wall. The ARC REF75SE, also stereo, plugged into the same circuit as the front end, had all the sonic struggles, compromises and limitations heard on the 160Ms run on separate circuits. What was a problem was that with the Ampzillas in place on separate circuits, lifting ground on the LEFT channel on the TVC caused the two B- fuses to blow on the RIGHT channel amp. Now, this happened with only modest ground noise coming through the speaker, so that ground difference caused a surge of current through the right amp's power supply, which did not get commensurately amplified through the audio path. I have to think through what was happening there. Both amps sounded clean up to the fuses blowing. Getting both of the amps on the same circuit as the front end eliminated this phenomenon.

As for the peak LED: This is much quicker to respond to transient conditions than a meter. ~300ms for a good meter; far less, even as little as a millisecond for an LED circuit. Ignore it unless it stays on for several seconds or you hear distortion. The Tron track that Keith plays for bass evaluation has, I suspect, bass content below the woofer response of the YG, which the amp nevertheless sees. At the volume level being played, you are going to see some flickering on that content even if you double or triple the amp power. Flickering should not be obsessed over. Your own amps without peak indicators are instantaneously clipping too. You just don't know it until it gets sonically egregious. Further, the amps were new and "stiff" around noon Friday when I first installed them for Keith. By 5pm or so, they were substantially more limber and flashing the peak indicator much less often. Totally normal. On other music and on analog, you don't see any peak flickering. Keep in mind, I could drive the same SPL in Keith's room with my 101db/w/m Zu Definitions with just ~16 watts. If Keith got Mac MC1201s, he'd only push that incipient clipping point on that track out 3db. This is the penalty of inefficiency. The Ampzillas are plenty strong for his room with the YG.

The Ampzillas sonically control the speaker well and punch through the complex crossover loads. Once limbered up, it is both musical and authoritative, and it's stable below 1 ohm. The amp is conservatively protected, both through active and passive (fuses) shutdown. I also have to note that for that Tron track, when I switched the L/R channels at the amps' inputs, the peak flickers followed the channel feed. The channel specific bass energy is just in the mix or master of the track.

Now, overall, Keith has to live with the problem of not having a true grounded outlet anywhere in the house. It's not what any powerful amp really wants to see, especially one fully balanced. I'll say that the m2tech amps sound smoother and not sterile at my house (they aren't my primary amps) but Keith's AC did not compromise their ability to dynamically control the speaker and energetically power it. In fact, the m2techs drive a bigger soundscape on the YGs than the Ampzillas, thus far. That may change. Overall, the Ampzillas are better, as I expected them to be. However much the lack of true ground might compromise a big amp's ultimate performance, the Ampzillas show none of the insufficiencies of either ARCs or the Luxman, which were simply underpowered relative to the speaker, in Keith's acoustic space. They also aren't distorting, harsh, amusical, and the resolution shortcomings of the original version sound well addressed in the Second Edition. Maybe Keith could find another amp with an nth degree more transparency. It's up to him if he wants to keep looking. I am quite sure that if found, without sacrificing other things the Ampzillas do well, the cost will be much higher.

The Ampzillas have a 2000VA PT, with lots of electrolytic storage. I expect them to audibly improve at a decreasing rate, over the next 1000 - 1200 hours.

Phil
 

microstrip

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(...) Whichever amp Keith decides is the perfect amp sonically, I would encourage him to get four of them. Even with 540 watts into 4 ohms the peak LEDs were lighting up. I am not saying I would even be able to hear a difference with four amplifiers, but, for me personally, purely psychologically and purely theoretically, I like the idea of extra headroom for effortlessness. Clearly to me YGs needs tons of power and current
(...)

I am somewhat astonished with such need of power - I owned the big Dynaudio Consequences (83dB/W , one of the less sensitive speakers I have ever seen) and could drive them to crazy levels with a Cello Duet - 350W at 8 ohm. Did anyone check for the voltage of the mains at Keith outlets?
Tube amplifiers are very sensitive to low mains.
 

213Cobra

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I am somewhat astonished with such need of power - I owned the big Dynaudio Consequences (83dB/W , one of the less sensitive speakers I have ever seen) and could drive them to crazy levels with a Cello Duet - 350W at 8 ohm. Did anyone check for the voltage of the mains at Keith outlets?
Tube amplifiers are very sensitive to low mains.

Voltage is fine. I checked it when he moved in. No low-mains condition. -Phil
 
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asiufy

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I don't think the issue here is playing LOUD. A 100W amp will play LOUD on the YGs. The headroom that Ron refers to, is for fast transient attacks played at reasonably loud volumes. That sort of stuff takes power (and headroom) with just about any speaker, to sound remotely realistic.
Having had YGs for years, I know exactly when an amp is lacking. The REF160M can play LOUD on the YGs, but it CANNOT do the loud, fast transient attacks, as there is no headroom.
I've found out you can get any amp to distort, if you try really hard. Keith seems to be having lots of fun trying just that :)
 

Folsom

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Phil what kind of panel does he have? It's a 1 story house correct? In that case it might be pretty easy to run one new line or two from the box to wall up above and drop down. Maybe not, but I've seen it done more than once. Also, a grounding rod for lightening can't get much easier to put in.

But ground isn't necessarily a good thing for audio all the time. You should bring over some RCA cables to try at some point though, as they are meant to have a floating ground in a sense.
 

213Cobra

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I don't think the issue here is playing LOUD. A 100W amp will play LOUD on the YGs. The headroom that Ron refers to, is for fast transient attacks played at reasonably loud volumes. That sort of stuff takes power (and headroom) with just about any speaker, to sound remotely realistic.
Having had YGs for years, I know exactly when an amp is lacking. The REF160M can play LOUD on the YGs, but it CANNOT do the loud, fast transient attacks, as there is no headroom.
I've found out you can get any amp to distort, if you try really hard. Keith seems to be having lots of fun trying just that :)
Exactly correct. -Phil
 

bonzo75

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Drive in an amplifier and head room is seen on soft notes, rise and fall of orchestra, and flow. Not crazy levels loud.
 
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KeithR

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Update: we tried an active tubed Melody preamp this evening to discern any kind of incompatibility.

Happy to report no loss of drive, bass, or dynamics vs the Music First TVC. There were peak lights in all the same spots as well. The tubed linestage did sound different, but I prefer the open, immediate sound of the TVC while others may prefer the slightly more texture and decay of the tubes are adding. I did think the bass was much better on the TVC.

I’ll let Phil expound more articulately, but I’m very pleased with the overall sound. When I returned from dinner I’m sitting here pretty stunned compared with what I heard even this morning. The amps have clearly settled in more and the soundstage has really expanded.
 

213Cobra

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Phil what kind of panel does he have? It's a 1 story house correct? In that case it might be pretty easy to run one new line or two from the box to wall up above and drop down. Maybe not, but I've seen it done more than once. Also, a grounding rod for lightening can't get much easier to put in.

But ground isn't necessarily a good thing for audio all the time. You should bring over some RCA cables to try at some point though, as they are meant to have a floating ground in a sense.
It's a pre-1962 house with original wiring. The panel is as far from the outlet Keith powers his audio from, as can be for the property. But yes, into the house, attic run, drop down could be done. He doesn't own the house so there is the matter of owner permission. I originally suggested getting an electrician to install a lightning rod outside his listening room and get at least that outlet grounded, for much less cost. Certainly is feasible.

We were just discussing this evening that he should consider running a single-ended loom from sources to amps. Full balanced doesn't always sound better, and the Ampzilla has a proprietary SE>BAL converter built in, with claimed no deleterious effects and input sensitivity for both is the same: 1v. For now the amps are breaking in nicely and getting limber quickly. The system is more dynamic, elastic and toneful than on Friday when I last heard it. The soundspace is also expanded, getting closer to the great projection of the m2tech monoblocks. The 'zillas fuse protection is very sensitive to static release from walking across carpet in the dry San Fernando Valley air and touching the TVC or an active preamp (I took one over today for a compare). I get why my digital gear is sensitive to static release but I am not sure why an analog amp blows 8A fuses with a little static release spark. Anyway, I think these amps are a fine match for the challenges the YG Hailey pose, and other good matches are likely to cost much more if they can be found.

Phil
 

213Cobra

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Update: we tried an active tubed Melody preamp this evening to discern any kind of incompatibility.

Happy to report no loss of drive, bass, or dynamics vs the Music First TVC. There were peak lights in all the same spots as well. The tubed linestage did sound different, but I prefer the open, immediate sound of the TVC while others may prefer the slightly more texture and decay of the tubes are adding. I did think the bass was much better on the TVC.

I’ll let Phil expound more articulately, but I’m very pleased with the overall sound. When I returned from dinner I’m sitting here pretty stunned compared with what I heard even this morning. The amps have clearly settled in more and the soundstage has really expanded.
Keith asked for an active preamp audition. I used to have a few, but moved one system to TVC strictly, and the other I interchange TVC and tube active pre. Sold off two of my active preamps since. What I have kept is a Melody Pure Black 101. It's a 6sn7, tube-rectified preamp that also uses 101D tubes for voltage rectification. It cost $4400 when I bought it. Australian designer; Chinese made, high-grade build Parts and build quality are on par with US and European competitive items in the $20,000 - $50,000 range. It has a very large dual choke power supply. It's a preamp but it weighs over 50 lbs. I also had a Melody p2688, which uses WE 403 or Ericsson 6ak5 pentodes for audio amplification. It was almost double the cost, even heavier, and somewhat more objective than the 6sn7 Pure Black 101. Point is, I have owned, used, auditioned and heard a vast array of top flight gear including preamps over the last 50 years, and these two Melody units are in the top 3 or 4 at any price. But you have to retube them from stock. The $5 rectifier and the flaccid bottom feeder 6sn7 tubes seriously undercut the PB 101. The p2688 does come with NOS WE 403 and the 101D are perfectly acceptable for voltage rec. The stock rectifier has to be heaved on that one too.

In the Melody 6sn7 preamp I hauled over to Keith's house today, I have a matched quad of unobtainium 1944 production Sylvania metal base, chrome dome 6sn7a. I bought them 25 years ago for relatively little because I intended to get a 6sn7 preamp when the right one came along. I sat on them until I found this Melody in 2007. It's magnificent more than half because of the 1944 production WWII 6sn7a tubes. The Shuguang Treasure cv181-z is the closest modern rival in this preamp. With the 1944 Sylvanias, the preamp is fast, incisive, objective bursty, musically faithful; convincing.

I was curious myself as I had a hand in Keith's decision to go to a TVC after he gave up his last integrated amp, so I wasn't advocating a change. Keith just wanted to hear what an active pre would do given all the late-breaking chatter in this thread questioning the TVC's ability to drive any of the amps needed for the YGS, well.

I use the Melody in my secondary system where it performs beautifully with a variety of amplifiers. Also understand that it has 23 db of total gain available, and it has three different outputs at "low," "high" and BAL impedances, unspecified. We ran it BAL in from the DAC and BAL out to the Ampzillas. In my experience, this preamp drives anything well.

On balance, listening to the Ampzillas on the YGs with both preamps, I preferred the TVC overall, but could probably tune the Melody to be an equal preference with some tube rolling. BUT, with the Ampzillas having input sensitivity of just 1v, there is a huge surplus of available gain. I think that would have been true even with the 2.4v i.s of the ARC 160M. We essentially got all the volume range needed from 6 o'clock (off) to the 8 o'clock position. The TVC actually dug a little deeper on some of Keith's synthetic and electric bass material, than the Melody. The Melody pushed a larger soundspace with more projection into the room today, but these were not large differences. The tube pre offered a little more midrange texture on strings and voices, but the TVC was slightly cleaner and more objective or absent euphonics. Both did a good job of keeping many simultaneous events distinctly hearable in crescendo.

Net: The TVC is not deficient in driving the amplifiers. The Ampzillas are blooming by the hour and are unfazed by the challenge of driving the inefficient, crossover-intensive YGs. They impose enough control and discipline to make the YG more coherent than normal for a multi-driver, crossover-intensive speaker. I am confident this will be a successful combination for Keith, and while one can argue whether more or less ultimate transparency is on tap, these Ampzillas do not impose a silicon devices signature. Easy to listen to but articulate and not obscuring details.

Phil
 

spiritofmusic

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If the Ampzillas hadn't worked out, would Keith have been forced to use way more expensive alternatives like D'Ags and Lamm hybrids?
 

213Cobra

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He still mentions Lamm curiosity. Which for many reasons I think he would rue the day. If the Ampzillas prove insufficient (I don't think they will), my backup recommendation was to be the SPL Performer m1000. https://spl.audio/professional-fidelity/performer-m1000/?lang=en

If neither of those, then he'd be headed to the megabucks amplifiers realm, with highly uncertain results. BTW, I don't think D'Agostino amps are the answer for anyone.

Phil
 
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andromedaaudio

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I have not seen measurements of those YG s but i think their impedance might even drop to 1 -2 ohms .
It will just drain most amps, not easy to get those speakers playing to their full dynamic potential.
Between drive and optimal drive there is a lot in between.
 

spiritofmusic

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Sorry to ask a stupid Q, but why are spkrs designed w such self imposed restrictions? To rule out 95% of amps?
 
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Folsom

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They aren't, Marc. They are designed for everything else and left over with tough impedances. However at their price point they surely don't fear someone being unable to afford an amp that can play them.
 

andromedaaudio

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Sorry to ask a stupid Q, but why are spkrs designed w such self imposed restrictions? To rule out 95% of amps?

It has to do with unit parameters , magnet -voice coil design etc, you cant make a high eff . loudspeaker with low eff individual units
How its wired internally is another , its all about choices a designer makes in the design process , its those choices which determine the end result .
All have different priorities .

Brg HJ
 

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