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post #61 of 73 Old 08-12-2019, 08:22 AM
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Quote:
Originally Posted by BufordTJustice View Post
Preliminary listening impressions. All observations are made for stereo listening:

I don't have speakers anymore. Virtually every source is now presented as a large, cohesive, 3D acoustic hologram. Even garbage while watching YouTube videos. Spatial cues have been exploded and stratified in all 3 dimensions.

The detail and texture in the mid-range and highs are now really exceptional. Zero sibilance and MOAR detail, but the additional sonic info is somehow less fatiguing.

Bass impact (not level) is heightened and bass texture is even more tightly defined at low and high SPL output. Upright bass performances are something you both feel in your feet and you also get the sense that you can see the player's fingers at work.

The sense that you can just get up and walk around inside the soundstage is palpable. I've got sonic sources literally dancing around my entire room, depending on the track and source (all CD rip or HR FLAC or Tidal MQA via my Bluesound Node 2).

The sense of depth of the Soundstage (both closer to you and further away behind the speakers and even far-past the back wall) is now very pronounced.

In sum, digital sounds smooth and full of body like vinyl. But also better than vinyl because you're swimming in detail and information.

I'm struggling to explain this but it's like a hybrid of a tube amp and class A solid state amp. All the smoothness and body of a tube amp, without any of the occasionally tubby or bloated/flabby bass. And seemingly unlimited current. But that smoothness carries across at as loud of a volume level as i dare. As do all the other things described above.

This thing is playing with the big boys now. No price caveats required.

Also, note that I'm using a Van Alstine Humdinger on John Hillig's and EddyZ's recommendation. This is a non-current-restricting DC blocker. My transformer is now SILENT even when i press my ear against the top grate. Confirming my suspicions that DC was present on my AC line.

Oh, and many thanks to @Eddy_Z . He and i have shared many enjoyable PMs and he led the way with sending his GFA-5500 to John at Musical Concepts first. So he's just been fantastic and a truly open book. Thanks Eddy!!


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You are very welcome BufordT, glad my recommendations worked out for you!


You have me pondering the Mini-Platinum upgrade on top of the LX Elite mod I had done, but I'd hate to fork out the shipping to get the amp there and back
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post #62 of 73 Old 09-30-2019, 03:21 PM - Thread Starter
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Originally Posted by Alex F. View Post
Thank you for the detailed reply.

So, not much of a sonic difference at all...

Actually, I am now intrigued and considering the modification. The price is quite fair. (The three-channel 5503 will obviously cost more than the two-channel 5500.)

What preamp are you utilizing?

Since I typed that reply to you, my Parasound started acting up. So I progressed to an Anthem AVM-30, then an Anthem Statement D1, and lastly to a Krell Showcase 7.1 (which was designed by Dan D'Agostino when he was at Krell). The D1 and Showcase are very close. The AVM-30 was a mostly lateral (but slightly more veiled) step from the Parasound Halo C2.


The Krell is what I seem to be settling on and it's a real show stopper. The analog section is literally the best I've ever heard. In fact, it's so good, that I actually prefer to use the analog outputs of the Bluesound Node 2 as opposed to the coaxial S/PDIF (the S/PDIF sounds identical between the Krell and D1). Granted, I'm not using the Node 2 without some changes; I run a shielded cat-7 RJ-45 cable to a mesh access point 15ft away, I use a shielded Pangea AC14 Mk II SE power cord, and I have disabled both wifi and bluetooth as I don't use either of them. This thing sounds markedly improved after those changes.


The Krell and the Statement D1 reall;y take the Adcom to another subtle level beyond what I have already described above. Mostly in terms of truly liquid, analog tone colors and body. When you listen to Sinatra's Centennial 4-"disk" Collection in 44.1/24bit FLAC (thanks HD Tracks), it really feels like vinyl now...in terms of emotional involvement. Hard to describe without venturing into meaningless audiophilic terminology. I can only think to say that I stayed up until well past midnight on a worknight last week just listening to things.


As for the 5503/5500, John Hillig seems to prefer the sound of those to the larger 580X (that he no longer works-on). If the rest of your system has resolving ability and you value musical reproduction, it's worth every single penny.


It really is like a truly neutral tube amp with NONE of the downsides to tube amps (life/longevity, drifting bias, limited current output, tonal colorations, limited damping factor/bass control, etc). I'm actually debating grabbing a 5503 like you've got to drive my centers and surrounds over my Acurus/Mondial A200X3 (which was also designed by Dan D'Agostino when he was at Krell). Not even an indichtment of the Acurus...but I could truly get into multi-channel music with an amp this excellent.

"If I had asked people what they wanted, they would have said 'faster horses'." -H. Ford | Krell Showcase 7.1/Anthem Statement D1 pre/pros | Musical Concepts' LX Elite Mini-Platinum Mod Adcom MOSFET GFA-5500 | Acurus/Mondial A200x3 | Bluesound Node 2/Apple TV 4K | Toshiba SD-9200 CD/DVD-A | Vizio 55" LED/LCD | L+R: Chane MTM Prototype | Chane A2.4 center | custom-finished Chane A5rx-c surrounds | Member: NATIA, LEVA, & AES.
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post #63 of 73 Old 11-14-2019, 02:28 PM - Thread Starter
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November 2019 UPDATE:

I had an opportunity to compare my GFA-5500 MCEP (Musical Concepts Elite Platinum) edition to a Bryston 4B SST2 and a First Watt F5 in my system. This local acquaintance later brought a Parasound A21 on another date.

I honestly was worried that upgrade-itis would strike again, despite how happy I was with the Adcom. WRONG. The Adcom 5500 MCEP bettered the Bryston in literally every area of performance in my system. The Bryston sounded flatter, presented more grain, and occasionally some of that bipolar glare....and it also had slightly less control over the bass below 80hz-ish. Not as much impact or textural information as the Adcom. The image the Bryston crafted seemed to primarily rest between the two speakers, rarely sourcing anything from outside the outer edges of the speakers. The Adcom makes silly stuff just dance all over my room, but still has fantastic center image focus, with lead vocalists seeming to emanate from a baseball point in the front of my room.

The First Watt F5 was up next (the Bryston only got listened to for about 30 minutes...we waited longer for the thing to warm up than to actually listen to it). The F5 sounded functionally identical to the 5500 MCEP, with the lone exception that the Adcom had better bass control, texture, and dynamism. Note that this was not a weak point of the F5, either. Oh, and then there's the little issue where the 5500 MCEP has literally 10 times the current delivery into any impedance when we take into account the A/B mode.

Lastly for the comparisons, the 5500 MCEP seems to come alive at every volume. Even playing ultra quietly past midnight (while the wife slumbers), It never failed to engage me in the music.

Also, these remain dead silent even with my delicate ear occupying the majority of the horn throat on Jon Lane's secret new speaker line (with Italian compression driver sitting on the other end, like a bear in a cave). Not a hint of hiss. Stunning.

I was nearly shell shocked. There really was more left in the tank. A lot more.

Upcoming is a Parasound Halo A21. Having heard everything so far, I actually don't think it will be a match for the subtle refinement of the Adcom.

Lastly, I've recently emailed with Nelson and he had warm things to say about the 5500 MCEP. I asked him what price point did he design the 5500 MCEP to, and he replied that he actually didn't; price was determined after design. Hinting that significantly less margin rested in these MOSFET models over the std bipolar Adcoms. I'm also going to guess that's one of the reasons they aren't made any more. Another reason: these output devices (and inputs, for that matter) aren't made anymore. Nelson also confirmed that he loves these input and output devices very much, that he has a stash of them, and that he still uses them in several of his current designs.

My eyes went wide after reading that. Wow. Sheesh. That explains it. These 5500's really are the hidden solid-state gems that everyone hopes to find on fleabay. Proved out by what I'm hearing, which is just stunning.

Hope everyone has a safe and happy Thanksgiving.
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"If I had asked people what they wanted, they would have said 'faster horses'." -H. Ford | Krell Showcase 7.1/Anthem Statement D1 pre/pros | Musical Concepts' LX Elite Mini-Platinum Mod Adcom MOSFET GFA-5500 | Acurus/Mondial A200x3 | Bluesound Node 2/Apple TV 4K | Toshiba SD-9200 CD/DVD-A | Vizio 55" LED/LCD | L+R: Chane MTM Prototype | Chane A2.4 center | custom-finished Chane A5rx-c surrounds | Member: NATIA, LEVA, & AES.

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post #64 of 73 Old 11-14-2019, 03:57 PM
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Interesting, one listen speaks a 1000 words. Amp can really make a difference in the sound, particular the sound stage, separation and the 3D.
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Not hooked up: Nakamichi Stasis PA-7 power amp, Velodyne VA1210 sub, Kef Reference Series center, Kef Bookshelf speaker, Monitor Audio bookshelf speaker, Infinity rear speakers. Acurus 3X200W amp.
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post #65 of 73 Old 11-15-2019, 09:09 AM - Thread Starter
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Originally Posted by alan0354 View Post
Interesting, one listen speaks a 1000 words. Amp can really make a difference in the sound, particular the sound stage, separation and the 3D.

I heartily agree. The 3D and sense of textural realism are the two most heavily affected aspects. But, there are amps that do indeed sound very similar (that group is growing as amp design improved across the industry).

And, i would qualify this. I’ve heard speakers with labyrinthine crossover networks, using lower tier parts, and mediocre drivers that really swamped and clouded any changes in amplifier even when both amps are VERY different . Swallowed them whole. No apparent difference. So, for people who have less than ideal loudspeaker designs, i really do believe them when they say they don’t hear a difference.

While i won’t say who made the speakers, they weren’t esoteric or terribly expensive. In fact, they were a relatively common brand here on AVS. Just two way stand monitors of easy impedance and relatively flat and linear axial response.

But, other like-priced offerings from competitors put amp differences on display starkly and immediately.

For boxes that don’t show that difference readily, I hesitate to opine what that could mean for the music. Though, the boxes that didn’t let these differences through didn’t immediately sound bad in any real sense. It’s not like they had a huge narrow Q peak or dip at any given frequency, or any blatant uncontrolled resonances.

In fact, a few loudspeakers that were slightly more difficult to drive on paper didn’t have any difficulties laying bare various amps I’ve used.




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post #66 of 73 Old 11-15-2019, 11:37 AM
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Originally Posted by BufordTJustice View Post
I heartily agree. The 3D and sense of textural realism are the two most heavily affected aspects. But, there are amps that do indeed sound very similar (that group is growing as amp design improved across the industry).

And, i would qualify this. I’ve heard speakers with labyrinthine crossover networks, using lower tier parts, and mediocre drivers that really swamped and clouded any changes in amplifier even when both amps are VERY different . Swallowed them whole. No apparent difference. So, for people who have less than ideal loudspeaker designs, i really do believe them when they say they don’t hear a difference.

While i won’t say who made the speakers, they weren’t esoteric or terribly expensive. In fact, they were a relatively common brand here on AVS. Just two way stand monitors of easy impedance and relatively flat and linear axial response.

But, other like-priced offerings from competitors put amp differences on display starkly and immediately.

For boxes that don’t show that difference readily, I hesitate to opine what that could mean for the music. Though, the boxes that didn’t let these differences through didn’t immediately sound bad in any real sense. It’s not like they had a huge narrow Q peak or dip at any given frequency, or any blatant uncontrolled resonances.

In fact, a few loudspeakers that were slightly more difficult to drive on paper didn’t have any difficulties laying bare various amps I’ve used.
That's the whole thing about the system. The system is only as good as the weakest link in the system. You cannot have a really good amp and expect to make a difference if the speakers are not up to par. May I add that speaker cables IS the 3rd variable in the system. Even if you have good speakers, good amps, the cables can be the bottle neck. I have done A LOT of experiments on amps and cables.


My main speakers is the JM Lab Spectral 913.1, I did comparison test using a pair of Monitor Audio Silver series bookshelf, I lost all the resolution and sound stage. I design power amps, it's getting to the point I think my JM Lab cannot do serve the job for comparing amps, I am shopping for a better speakers. I am eyeing on either the JM Lab Focal Diva Utopia or Alto Utopia.



Speakers is the most important part in the system. I consider the job of amp and the cable are to bring out the best of the speakers. So in order to talk about the amp and cable, you have to have define the speakers first.


Also, some speakers are easy to drive, some are very hard to drive. Amps and cables really become important for the speakers that are hard to drive and you can tell easily whether the amp is inferior. My JM Lab is one of those very hard to drive 4ohm speakers. When I first got them and hooked onto the existing system to replace my Kef Uni-Q floor standing, I did not hear much difference. The Kef was the top of the line of the Uni-Q series with dual woofers. I was so disappointed that the JM Lab was 3 times the cost and not much improvement. Then I started to double up the cables. Each pair improved the sound until 4 pairs of 12 gauge Monster cables for each speaker!!! It is my theory that for more difficult to drive speakers, you need amps with high damping factor and cable with low loss ( low inductance, NOT LOW RESISTANCE).



I hate to say this, price do make a difference. High price doesn't imply good sound quality, BUT good quality definitely would not come cheap. I can speak for power amp. Each of the amp I designed and built cost me $1000 just for the parts. Like you said, good speakers use good quality crossover components. Good quality components means LOW LOSS, this make the impedance spike and dip much sharper.......Meaning it's harder to drive. This is all engineering. I am born cheap, I don't believe in paying just for the sake of paying. But what I said is all from the point of view of engineering. I am shopping for a used pair of speakers because those that I want are over $10K new. There's no way I am willing to pay over $10K for a pair of speakers. But I need a pair right about now. I am hoping to get a pair below $K used.
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post #67 of 73 Old 11-15-2019, 12:51 PM
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Originally Posted by alan0354 View Post
That's the whole thing about the system. The system is only as good as the weakest link in the system.
Which could be:
amp
speakers
room acoustics
music source(s)
speaker placement
the human's expectation(s) and perception(s)
"faulty" wires/cables
improper setup/calibration
and.... probably more.



If you can’t explain it simply, you don’t understand it well enough – Albert Einstein
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post #68 of 73 Old 11-15-2019, 02:07 PM
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Originally Posted by Ratman View Post
Which could be:
amp
speakers
room acoustics
music source(s)
speaker placement
the human's expectation(s) and perception(s)
"faulty" wires/cables
improper setup/calibration
and.... probably more.
Of cause, no need to mention those. After all those are optimized, the amp and speaker cables do make a difference in the sound as long as the speakers are good enough to tell the difference.


More importantly, even the room is not optimize, if the speakers are good enough, the amp and cable still make a difference.

Own designed power amp, own designed preamp, JM LAB Spectral 913.1 speakers, Rythmik F12SE sub.
Not hooked up: Nakamichi Stasis PA-7 power amp, Velodyne VA1210 sub, Kef Reference Series center, Kef Bookshelf speaker, Monitor Audio bookshelf speaker, Infinity rear speakers. Acurus 3X200W amp.

Last edited by alan0354; 11-15-2019 at 02:11 PM.
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post #69 of 73 Old 11-15-2019, 02:12 PM
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Of cause (sic), in your opinion(s), which is ultimately the amp and speaker wire. Not the other "stuff" I mentioned previously. Okay.



If you can’t explain it simply, you don’t understand it well enough – Albert Einstein
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post #70 of 73 Old 11-15-2019, 02:32 PM
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Of cause (sic), in your opinion(s), which is ultimately the amp and speaker wire. Not the other "stuff" I mentioned previously. Okay.

Quote:
Originally Posted by alan0354 View Post
......................
Speakers is the most important part in the system. I consider the job of amp and the cable are to bring out the best of the speakers. So in order to talk about the amp and cable, you have to have define the speakers first.

You read my post, I said with a GIVEN PAIR OF SPEAKERS, amp and speaker cable.


Read the post.

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post #71 of 73 Old 11-15-2019, 02:44 PM
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You read my post, I said with a GIVEN PAIR OF SPEAKERS, amp and speaker cable.


Read the post.
Read my post. What's the "GIVEN PAIR OF SPEAKERS"?

There's more than your speaker choice, your DIY amps and speaker wires.


As I tried to convey... there are more parameters to take into consideration.



If you can’t explain it simply, you don’t understand it well enough – Albert Einstein
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post #72 of 73 Old 11-15-2019, 02:59 PM
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Originally Posted by Ratman View Post
Read my post. What's the "GIVEN PAIR OF SPEAKERS"?

There's more than your speaker choice, your DIY amps and speaker wires.


As I tried to convey... there are more parameters to take into consideration.
Read the post, I said even if the room and everything else is NOT optimized, with a given pair of speakers, amp and speaker cable do make a difference if the speakers are good enough. It's not like if you mess up the room and position, then ALL systems sound just as bad. At ANY given room/placement, the good system is still going to sound a lot better than an average system in the same room/position. Period. Of cause, unless your system is so bad that the room/placement won't even help!!!
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Not hooked up: Nakamichi Stasis PA-7 power amp, Velodyne VA1210 sub, Kef Reference Series center, Kef Bookshelf speaker, Monitor Audio bookshelf speaker, Infinity rear speakers. Acurus 3X200W amp.
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post #73 of 73 Old 11-18-2019, 10:05 AM - Thread Starter
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I said even if the room and everything else is NOT optimized, with a given pair of speakers, amp and speaker cable do make a difference if the speakers are good enough....

Agreed in full. I feel like this derailment can be over now.

"If I had asked people what they wanted, they would have said 'faster horses'." -H. Ford | Krell Showcase 7.1/Anthem Statement D1 pre/pros | Musical Concepts' LX Elite Mini-Platinum Mod Adcom MOSFET GFA-5500 | Acurus/Mondial A200x3 | Bluesound Node 2/Apple TV 4K | Toshiba SD-9200 CD/DVD-A | Vizio 55" LED/LCD | L+R: Chane MTM Prototype | Chane A2.4 center | custom-finished Chane A5rx-c surrounds | Member: NATIA, LEVA, & AES.
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