ack's system - end of round 1

LL21

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Wow, Ack. That is some serious dedication. Well done! I really admire the meticulous nature with which you have approached your entire system...and the technical elements as well which I admit I am loathe to try and [literally] burn my fingers doing it. My primary areas of careful, critical listening has been around isolation with various products, a degree of grounding and a degree of power but not anywhere near in the class of commitment you have shown.

Congrats.
 
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ack

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Thanks Lloyd, thanks sbnx! One thing I should add is that all 7 of these cords took at least 24 hours to come to life, and around 4 days to fully settle. I found that weird at the very least. Would love to hear what others' experiences have been.
 

ack

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The sound of a Resistor

This is a crazy hobby... talking about dedication, here are some 46 resistors - Mundorf, Duelund, etc - that I have experimented with, just for the panel in-series resistance, for a total cost of more than $1000. On top of that, there are 6 more sitting on the speaker, plus many more inside the cabinet as part of the crossover, plus others so heavily used that I had to throw them away. I am guessing some $2000 in total over the years just for resistors.

IMG_4312.JPG

But that's not the point... the point is that they all have a clear sound... and while I thought the carbon [black] Duelund would easily top them all, the reality is that everything but the Mundorf MResist Supreme have a rather soft, dull sound, and really nothing sounds as clear and in control as the Mundorf. This has been a major revelation for me, and am glad that I picked Mundorf all around for the internal crossover some 10 years ago. These products are just world-class, and am so glad to see them in most Magicos and other such world-class speakers. Resistor values that I have worked with range from 0.10 ohms to 5.6; even small values like 0.22 ohms sound different between manufacturers... fascinating

-ack
 
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ack

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Relentless Assault On Noise: "Timbre and Articulation" Realized

In post #1 a decade ago, I stated that my goal has always been Timbre & Articulation, and this is the first time I can safely say, this has been achieved to an extremely high degree.

Before getting into the details, I wanted to catalogue the changes in the last 12 months, many described upthread, which have been very instrumental in this feat, but due to covid, no one else has heard:

1) Finalizing my custom Mundorf-based crossover design on the panels and woofers: a beautifully executed electrostatic hybrid is something to behold. I wish the factory would do what I have done over the years
2) Purchasing the Yggy2 DAC
3) Finalizing the Alpha DAC modifications and volume-control setting
4) Redoing the VPI's suspension with Isodamp
5) Isolating the A90 from the arm with isodamp
6) Adjusting anti-skate for maximum tracking and minimum distortion
7) Reverting back to the HD setting on the MIT speaker cables' box
8) Redoing my tuner's power supply with Mundorf capacitors and those Vishay HEXFRED power diodes also used in the Alpha DAC and Pass XP-25 Phono
9) Fully shielding the XP-25 phono with mumetal, main unit and power supply, enabling me to turn up gain to its native 76dB for maximum dynamic headroom, with virtually zero hum or hiss
10) Replacing the XP-25 umbilical with the fabulous Tubulus (thanks Marc!)
11) Suspending the XP-25 main unit on Isodamp
12) Purchasing the fascinating Shunyata Denali 6000/S V2 fed by a Venom V10 XC cord. It drives the amps, preamp, DACs, phono, tuner, CD transport. Unlike the Everest which features much higher filtration, the amps can be plugged into the Denali
13) 13 more Shunyata power cords:
- Venom 10XCs to the amps
- Venom NR V10s to the preamp, phono, DACs, transport, MIT power distributor to ancillaries
- Venom NR V12s elsewhere, including the VPI's motor (more on that below)
14) Air flow control to the amps, using ultra-quiet fans and a Variac
15) Shielding of the Yggy2's transformers with mumetal
16) Lifting of the amps' grounds
17) Shunyata Venom RCA interconnects for the Alpha DAC

The Denali offers very wide spectrum of VHF noise reduction according to Shunyata's specs, while the NR cords appear to complement it with a more narrow field. There is also audible improvement going from an NR V12 to an NR V10, and these V10s are an absolutely groundbreaking product (see also user comments on MusicDirect's web page), as I am sure are their more expensive cords. For me, cost was a consideration as well as sticking with copper-only designs.

It was important to me to properly understand what noise reduction was doing, and approach it in a holistic way. The net effect has been multi-faceted:

- Evening of musical notes by removal of certain euphonic colorations (which might be interpreted as robbing the music from its excitement),
- Extreme linearity in the entire audible spectrum
- Major reduction in distortion (staggering in fact)
- Complete, realistic notes, with beautiful long sustain
- Extremely high purity of timbre and very high articulation, to be able to hear everything in a recording
- Much higher dynamic headroom
- Blacker backgrounds, increasing transparency
- Perhaps unexpected, plugging an NR V12 to the VPI's motor rendered an audible improvement in attack with all notes, a more vivid presentation if you will
- Very significant drop in radiated magnetic fields, as measured with a magnetometer
- Palpable images
- Music just draws you in and sounds BEAUTIFUL, if not utterly realistic with the right recordings. My son is certain transfixed. You've GOT to listen to the timbe and power of the violin on redbook HDCD, out of this heavily modified Alpha DAC - e.g. the Janaki Debut CD

In terms of impact of any one of these upgrades, the Shuyata stand apart - a simply profound effect everywhere, as documented earlier in this thread.

For the first time in some 40 years in this hobby, I've been able to listen to Mahler's 2nd with the BSO & Ozawa on CD end-to-end with no distortion. This is a major feat in here. This symphony and recording have it all: power, emotion, brio, contrast, complexity, beautiful strings, timpani to die for, stupendous chorus, the organ, sopranos. It's all there inscribed on the silver disc, at redbook resolution.

This is my first personal Wow moment in here. And yes, analog still sounds superior to my digital.

I'm just going to leave this image here for reference
1606586551801.png

-ack
 

sbnx

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Congratulations! That was a LOT of work but I am certain you feel very much worth every moment of the effort invested.
 
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ack

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Congratulations! That was a LOT of work but I am certain you feel very much worth every moment of the effort invested.
Thank you! Yes, this has been an excruciating effort, almost day in and day out, oftentimes playing the same tracks over and over again as I have said before, with frustrations often running high; followed by replacing one power cord at a time. But the results are truly rewarding, as I am sure you also experience in your own system. The covid isolation has helped in dedicating the time to do it all. As you can probably also attest, it all starts with clean power - the difficult question though is: what does that look like.
 

Ron Resnick

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Congratulations, ack! I am very happy for you that you have achieved your original goals!
 

spiritofmusic

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Ack, have had a fascinating experience with the IsoDamp you favour.
I've installed a new SOTA Eclipse Condor tt motor. It sits in a cylindrical pod, the bottom half as empty void.
This means there's a certain amount of ringing, that translates as a mild steely colouration. So under advice from a fellow owner of this motor, and remembering your advocating IsoDamp, I've used some thin strips attached to the interior of the pod void.
Interestingly, coating 100% of the pod with IsoDamp is too much, leaving a dead sound.
After some ABA listening, I've settled on no more than 25% of the pod interior damped.
 

ack

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spiritofmusic

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Ack, my issue with IsoDamp is that one can maybe use too much. Anything more than 25% coverage of interior of my tt motor was deleterious. Anything less than 25% didn't quite feel damped enough.
 

sbnx

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Thank you Ron!

Marc, Isodamp - as you found out - is phenomenal; glad you get great results. And there is good reason Magico started using it as well years ago on the front baffle, and then in their QPod feet. BTW, I got more of these jeweler's stainless steel blocks https://www.amazon.com/gp/product/B000RAZR0G/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1 and here's what they look like in real life and weigh a little less than 2 kilos

View attachment 71952 :
Ack, you find the most interesting things. Is that the 1" rubber stamping block you have sandwiched in between the metal plates? Can I ask what you are using this under? (I tried searching the thread but didn't find any other reference to it)
 

ack

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Ack, my issue with IsoDamp is that one can maybe use too much. Anything more than 25% coverage of interior of my tt motor was deleterious. Anything less than 25% didn't quite feel damped enough.

Yeah, no disagreement that it may also have a negative effect; I have no experience with it inside motors, so can't say much more. I suspect your motor requires some rigidity as well, like mine. I use the Isodamp underneath my motor, and only as such needed as to no longer hear whirring on the shelf with a stethoscope. The motor body still exhibits whirring.
 

ack

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Ack, you find the most interesting things. Is that the 1" rubber stamping block you have sandwiched in between the metal plates? Can I ask what you are using this under? (I tried searching the thread but didn't find any other reference to it)

These are metal blocks to weigh things down, much like those HRS blocks, but much heavier and effective. I use them on top of the amps, preamp and transport, to stop the plates from vibrating. Don't ask me if they make a sonic difference :) These ones in the picture have that concave shape and are painted black, for whatever reason. They just look cool as is. I don't think I have posted about them, I think they came in a private discussion with Marc and HRS. What did make a sonic improvement is to place piles of marble tiles on top of the MIT speaker boxes, about 6 kilos per, in addition to the mumetal around them. Those MIT boxes do react to sympathetic vibrations - not good.
 

spiritofmusic

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Ack, I might try that. The new motor is currently on an 8mm thick Symposium Svelte pad, soon to go on one twice that thickness.

In the new yr I'm gonna try your idea of IsoDamp as top chassis damping. Your suggestion was 0.25" thick IsoDamp mass loaded by these steel bench blocks

At 4"x4" each, I'll try two to four blocks each on my preamp and preamp psu, three to six on my cdp, one on my phono, and a couple on my analog psus.
 
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sbnx

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Well, your recent post inspired me to finally get off my rear and I ordered a couple sheets of the isodamp. I'm excited to see what that might do in a few locations. Of course I don't have a TT so I won't be using it there.

Do you know if it leaves any oily residue on the surfaces it is used on behind?
 

ack

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Well, your recent post inspired me to finally get off my rear and I ordered a couple sheets of the isodamp. I'm excited to see what that might do in a few locations. Of course I don't have a TT so I won't be using it there.

Do you know if it leaves any oily residue on the surfaces it is used on behind?
So it was originally claimed years ago that it can stain the surface it sits on. I can tell you that, after 10 years, it leaves a tiny wet mark that can be easily wiped off with isopropyl alcohol; nothing egregious, and I do use it under my speakers directly to the hardwood floor with no issues, and with major sonic gains. In certain places - like the turntable platter interface - I do use a very thin layer of Saran Wrap so as to not stain the vinyl; mylar would have been better
 

ack

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The Schiit Yggdradil 2 + Shunyata NR + Spectral active buffer



To make a long story short, this is really great redbook digital sound on par with analog.

Background:

1) That the Shunyata Venom NR power cords and Denali 6000S/v2 have had a stupendous effect on the system has already been described. The last piece - an obsession, really - was to make the Yggy2 sound truly analog, with the right recordings.
2) The 30SV preamp has an active, discrete, unity-gain, balanced input buffer at input 6, which is slated to be used with DACs (more on that below)

The Yggy's balanced-out sounds clearly more refined that its RCA (there is a summation circuit in the latter), but the output voltage (claimed to be 4V) appears to overload the Spectral 30SV's RCA inputs when using XLR-to-RCA adaptors, and oftentimes the sound is too forward, euphonic and somewhat distorted. On the other hand, running XLR-to-RCA to the balanced-in module - which I have done with both of my DACs, as an experiment - tones the sound down by some 9dB and is too soft, though smooth. And having run the Yggy2 XLR-to-XLR in the past did not render better results; but that was before the Shunyata stuff.... this is now different...

The Spectral 30SV's 304 Balanced Input Module​

From their bulletin:

The Model 304 Balanced Input Amplifier
To address the shortcomings inherent in the output sections of todays high-end digital processors, Spectrale ngineers have developed the model 304 balanced input amplifier. The model 304 is a discrete, high-speed class A unity gain buffer operating on unusually high voltage rails. This fully push-pull topology is derived from our innovative SDR-4000 I/V balanced amplifier and features superior performance to any IC buffer. The model 304 is design optimized as a discrete buffer amplifier unlike conventional IC input buffers.Custom discrete buffers are a rarity in audio today but still are found in the best ultra-premium recording consoles.

Although difficult to design and hugely expensive compared to op-amps, the optimized discrete input buffer is the only uncompromised solution for interfacing digital audio components and amplifiers.Spectral engineers have taken the discrete input buffer to the next level in the 304 balanced input amplifier.Custom matched J-fet transistors are employed in the cascode front-end. Built to Spectral specifications for low gain applications, the hand built devices lower crossover distortion, noise and improve common mode rejection. Bandwidth, slew rate and distortion are all vastly superior to conventional buffers. The speed and resolution of the 304 balanced input buffer are exemplary and perfectly compliment the superlative performance of the new G3 line section of the DMC-30SV

Well, I decided to get a pair of Shunyata XLR Venom interconnects (all-Ohno copper, shielded), and the results have been rather staggering. Everything Spectral writes is true in this system, starting with lower noise, which renders very analog timbre and even more detail and transient speed. Noise is really a killjoy. Next, nary a hint of distortion with the loudest of passages and no overload. How they do it is beyond me, but it works as advertised, and there is zero loss of information thanks to those custom J-Fets which comprise the unprecedented and ground-breaking SV technology. This redbook sound is on par with my analog, it's as simple as that.

Let me just say this: The Spectral engineering team is a bunch of geniuses, and apparently, so is Schiit's in this DAC.

Happy New Year to all!
 

ack

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Vishay Dale resistors for crossovers: looking at MIL-PRF-18546​

If you care to improve upon the beautiful Mundorf Crossover MResist, read on...

This military spec relates to power resistors mostly, but I thought I'd try Vishay's versions and compare against my Mundorf MResist in the in-series resistance I have for the panels, and the results are interesting.

Specifically, I am using two non-inductive 2.5 ohm 1% Vishay NH0502R500FE02 (NH = non-inductive, RH = inductive) in parallel and comparing with the same value Mundorf 2% MResist (also non-inductive).

At half the price, the Vishay slightly outperform the Mundorf, with a faster, crisper sound, quite evident with strings. The Vishay also appear to be more linear, as judged by some somewhat pronounced notes coming out of the Mundorf, flatter from the Vishay. The Mundorf are just a tad rounder and slower, sweeter perhaps, as if they store some energy. It takes a very high resolution system to be able to tell these differences, but they exist.

The Vishay are claimed to use the Ayrton-Perry non-inductive wounding technique https://en.wikipedia.org/wiki/Ayrton–Perry_winding and I don't know what the Mundorfs use - maybe the differences lie therein. The Vishay are likely here to stay.

IMG_4489.jpg
 

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