I think my System is virtually finished

[GDHAL]

Hal any format. A great recording is a great recording. BTW Steve how did you implement the volume control ??? Last thread was removed.

charles

Charles, you are most qualified of anyone on this forum to vouch for the quality of my digital recordings. Sorry folks. no analog here, been there, done that. To name a small (EDIT3: small as in .01%) portion of what I have that is the most pristine you could ever obtain (as of today given today's technology):
--------------------------

Grateful Dead - Europe '72 (50th Anniversary) (2022) Remastered LP [24-192]

50th Anniversary remaster version of the original EUROPE '72 album. This has been newly mastered by Grammy Award-winning engineer David Glasser with newly restored audio by Plangent Processes.
------------------------

Oh, and if you don't like any kind of "artificial" digital processing, I have *every* 24/96 Grateful Dead "Ultra Matrix Soundboards" shows *ever* released. If you don't think Grateful Dead are the pinnacle of where analog or digital recordings can go, google it.
------------------
Saint-Saens_Symphony_No3_24-96_2.0
The Symphony No. 3 in C minor Op. 78 was completed by Camille Saint-Saëns in 1886 at what was probably the artistic zenith of his career.

Digital: Weiss ADC2 Analog to Digital Converter
Mytek ADC192 Modified by Steve Nugent of Empirical Audio
Lynx AES16 used for digital I/O
Antelope Audio Isochrone OCX Master Clock
Weiss Saracon Sample Rate Conversion Software
Weiss POW-r Dithering Software
Analog: Studer 810 Reel to Reel with JRF Magnetics Custom Z Heads & Siltech wiring
Aria tape head pre-amp by ATR Services
Manley Tube Tape Pre-amps Modified by Fred Volz of Emotive Audio
Cables: Purist Audio Design, Pure Note, Siltech
Power Cords: Purist Audio Design, Essential Sound Products
Vibration Control: Symposium Acoustics Rollerblocks, Ultra platforms, Svelte shelves
Sonic Studio CD.1 Professional CD Burner using Mitsui Gold Archival CD's
---------------------
Nagra 70th Anniversary Collection (2022) [24-352.8]

NAGRA is on a course to become a major force in the world of vinyl. Having just launched their first-ever turntable - the "statement" level, Reference Anniversary turntable/tonearm system - they now follow with the production of The Nagra 70th Anniversary 45rpm double vinyl album. Mastered at 2xHD on Nagra equipment and cut at famed Bernie Grundman Mastering, the set is pure analog from analog master tapes. The LPs feature tracks from Bill Evans, Louis Armstrong, Monty Alexander and Buddy Tate along with some amazing audiophile tracks recorded on the legendary Nagra IV-S tape machine.

Release Date: October 7, 2022
-------------------------

My list goes on and on and on. The aforementioned will suffice for now.

 

Best.

Hal

[steve]

As a suggestion, why don't we start another string if we are going to stray off subject into recording quality.

Thanks.   

steve

[GDHAL]

not until you tell us how you can make the perfect playback gear when the recording quality is all over the map.

doug s.

As a suggestion, why don't we start another string if we are going to stray off subject into recording quality.

Thanks.   

steve

Doug, thank you!! I love a sense of humor, especially when in good spirits. And, even more so when the question you pose is precisely the point!

Best.

Hal

[rollo]

  Doug ain't no dummy.

charles

[steve]

Steve how did you implement the volume control ??? Last thread was removed.

charles

Yes, that takes a lot of consideration due to the complexities involved Charles.

1. The volume contol resistance is the weak link, whether passive or directly into a gain stage within
the same inclosure (no interconnect cable needed).

2. By itself, the volume control will affect the highs, and lows if the source is capacitively coupled. A
passive is really not the way to go. It would be better to place the control inside the integrated
amplifier itself (if possible) so as to eliminate the interconnect cable (ic) and minimize the capacitance.

3. The volume control is generally placed to feed the gain stage. With this placement, and with most
tubes plate to grid capacitance (Miller capacitance is gain times this capacitance), this setup will be most
influential in determining the high frequency response. (Long ics with high capacitance will also affect
the high frequency response. See more below.

The plate resistance (Rp) and plate load resistance (RL) into the load will also affect the high frequency
response. (The output capacitor will determine most of the low frequency response.)

Example: Suppose we use a 6SN7 family tubes, 10k ohm RL, 8.5k ohm Rp. Parallel is 4.6k ohms.

With 250pf output load capacitance (ic + load input capacitance), we can expect to see  -0,75db at 550khz.
With 100k volume control, mid resistance, 6sn7 input, 40pf Miller capacitance,                 -0,73db, 550khz
With 25k volume control, mid resistance, 6sn7 input, 40pf Miller capacitance,                   -0,25db, 550khz

100k control, mid resistance, 40pf             -0,15db at 100khz
25k control, mid resistance, 40pf               -0,012db at 100khz

------------

6dj8 family tubes, 4.3k ohm RL, 3.3k ohm Rp, Parallel 1.86k ohms.

With 250pf output load capacitance (ic +load input capacitance),                                      -0,48db at 550khz.
With 100k volume control to 6dj8 input, mid resistance, 20pf Miller capacitance,               -0,5db
With 25k volume control to 6dj8 input, mid resistance, 20pf Miller Capacitance,                -0,08db

100k control, mid resistance, 20pf                    -0.045db  100khz
25k control, mid resistance, 20pf                      -0.003db     100khz

The deviations seem small, yet they are important.  When one considers most specifications are within +/- 0.1db at oly 20khz, +/- 0,1db means little.

4. Next, let’s consider adding a cathode follower etc to the wiper arm of the volume control to eliminate the  Miller effect consideration. There are different ways to consider, but each will add  complexity and will deteriorate the musical quality.

Suppose we add a cathode follower, or similar to lower the output impedance of the preamp. With 250pf output load, we have an incredible response to over 500,000hz (500khz). If we add more load capacitance, we are starting to approach a 0,001uf capacitor. But is that really desirable?

I hope this helps Charles, and others when considering a design.

----------

"not until you tell us how you can make the perfect playback gear when the recording quality is all over the map."

It is more desirable to enjoy the music with as many sonic faults, distortions, and colorations as possible.

Interesting philosophy.

I suppose if hard rock only, one would want to add as much/many distortions as possible.
 
But as 26 RCA engineers state, that is not high fidelity reproduction. (RCA Radiotron Designers Handbook)
This discussion/string is dealing with high fidelity reproduction.

My lab work over the decades deal with ridding the playback of its many sonic faults for a better, more
natural listening experience.

We have to start somewhere if we wish to improve the musical experience.
I have taken the steps to start with the playback.

Cheers

steve 

[steve]

Gentlemen, this string is exclusively concerned play back accuracy.

I have considered and Playback should be the first place to start improvements, and then afterward,
the recording quality. But even in playback territory there are problems, as mentioned below.

There are some higher quality recordings, and improving playback will reveal
those recordings. Hopefully, those high quality recordings will set the standard for others to follow.
However........

I have seen what happens to superior parts over the last decades. Let's present an example,
capacitors. Due to improper testing methods, wrong values ufd, and using inferior quality testing
components, the superior capacitors are discredited, given low numbers, and become extinct.

Instead of excellent/accurate capacitors costing $20.00/each, the cost is now hundreds
and even thousands of dollars for each capacitor, whose accurate sonic quality we do not know.
Who wants to purchase such expensive parts and find they are inferior, or no better than the less expensive
parts.

How is Audio playback to improved when the better quality parts are diced into extinction. And those
same high quality parts are necessary for recording components.
 
So the merry-go-round continues with little, if any sonic improvements.

Cheers

steve

[GDHAL]

Gentlemen, this string is exclusively concerned play back accuracy.

If you wish to discuss recording accuracy, please start another string.

Cheers

steve

Great point, Steve. Specifically, with your point to play back accuracy,
please answer Charles' question as far as volume control regardless of what method you implement and the accuracy that ensues from your implementation.

My question, how would your implementation affect the end result, which is the enjoyment that the listener has while listening to music?

Furthermore , do you think in any way that your implementation is going to result in an *audible difference" versus any other or different implementations?

Best.

Hal

[steve]

Gentlemen, this string is exclusively concerned play back accuracy.

If you wish to discuss recording accuracy, please start another string.

Cheers

steve

Great point, Steve. Specifically, with your point to play back accuracy,
please answer Charles' question as far as volume control regardless of what method you implement and the accuracy that ensues from your implementation.

My question, how would your implementation affect the end result, which is the enjoyment that the listener has while listening to music?

Furthermore , do you think in any way that your implementation is going to result in an *audible difference" versus any other or different implementations?

Best.

Hal

Please re-read my post to Charles (Rollo) as the answers are contained therein. 

cheers

steve

[GDHAL]

Gentlemen, this string is exclusively concerned play back accuracy.

If you wish to discuss recording accuracy, please start another string.

Cheers

steve

Great point, Steve. Specifically, with your point to play back accuracy,
please answer Charles' question as far as volume control regardless of what method you implement and the accuracy that ensues from your implementation.

My question, how would your implementation affect the end result, which is the enjoyment that the listener has while listening to music?

Furthermore , do you think in any way that your implementation is going to result in an *audible difference" versus any other or different implementations?

Best.

Hal

Please re-read my post to Charles as the answers are contained therein. 

cheers

steve

Hi Steve. If you're referring to your post to Charles December 16, 2022, 05:19:17 PM, I reread it at your suggestion.

I couldn't glean from it the answers to my questions which is how do you feel or know your implementation will positively affect the overall *enjoyment* that the listener experiences and whether or not your implementation by virtue of it being better relative to other designs and/or parts used is clearly audible that most would conclude the sound is "better" as opposed to "different".

I suppose the essence of my question is, in your opinion, at what point in the theoretical best amp/preamp/integrated design that you or anyone else can build does it become a matter of "so what"? (Miles Davis, or not, reference)

Best.

Hal

[rollo]

  Thanks Steve. Not an easy task I see.

charles

[steve]

  Thanks Steve. Not an easy task I see.

charles

You are correct Charles. A few points if I may.

1. I used 25k volume controls although that requires a larger source output coupling
capacitor. 50k would only marginally reduce the high frequencies if I remember correctly.

2. Some are mid resistance frequency response (FR) measurements, that is around 2 o'clock
on the shaft setting (A taper). Less rotation (less resistance to ground) and more rotation (less resistance
to the source) would improve the high frequency response.

3. We are using a nice control. I remember when someone actually used a 250k or 500k cheapy control
and claimed better highs mid resistance. That would be because of the physical materials, elements, used
actually distorted the highs. It had highs, but questionable quality.

I hope this helps all who read this string.

cheers

steve

[steve]

I made a change that has worked out very nicely. I was using a pc mount 26 turn trimming
potentiometer in parallel with resistor for precision adjustment. But even using a Vishay Bulk Foil
potentiometer was not stable enough as the contact resistance changed with time due to mechanical
play.

The wiper arm/resistance strayed too much, so I have been testing another technique
where I could use a short 18 gauge wire in place of a pot. Wire has better resistance stability. Little
inductance to speak of. Working great.

cheers

steve

[steve]

Performed another experiment a few weeks ago that involved bypassing the full range driver polyprope crossover
capacitor "X" with polystyrene capacitor " Y ", and subsequent added Y caps added in series with Y to reduce the capacitance. (Y capacitors are the same capacitors, each 47pf in value.)

What value of total bypass capacitor Y would it take to Not alter the sound that I normally hear with
just X capacitor?

X capacitor was 50 ufd. That is 50 times 10 to the minus 6 farads. Y 47pf is 47 times 10 to the minus 12 farads.
47pf is ~1 million times less than 50ufd.

I started with a Y bypass capacitor, 47 pf, 630 volts.
The sound was horrible as the highs were accentuated way too much. Nasty indeed.

I series one Y cap with one Y capacitor for 23pf; still way too bright.

Then another series Y for three 47pf capacitors in series, 16pf; still too bright.

I finally stopped with 4 Y caps in series for 12pf across the 50ufd; and still brighter than
without the 12pf across X 47ufd capacitor.

Additional info.

At 20khz, the reactance of Y 12pf capacitor is ~663,000 ohms. That is across the 50uf poly
capacitor with a reactance of ~0,159 ohms. So the paralleled reactance of Y total, 12pf, is
~4,100,000 times larger than the size of the 50 uf's reactance. Phase change is virtually zero.

Now let's say the signal voltage varies directly proportional to the capacitance change. It will probably
be less, but let's be conservative. We would be talking ~ -132db down change from just the lone 50 ufd.

Interestingly, the result correlates with other tests I have performed. Examples:
 
A. I was using 10 stranded 18 gauge wires in parallel in each speaker leg. Subtracting or adding
one wire from one leg made a clear sonic difference.

B. Rotating a speaker 0,5mm made a sonic difference, both frequency response (FR) and spacial etc.

C. Altering the RIAA R1 resistance by less than 1 ohm in ~20,000 (very easily heard),

D. Moving a lead wire on a crossover choke by a fraction of an inch.

E. Torquing the speaker wire jacks affected the sonics.

F. Changing wire types, switches affected the sonics.

As mentioned above, our ears are incredibly sensitive. Far beyond what is normally considered.

Another conclusion is the laboratory system (now home) is incredibly mask free.
Virtually nothing to cover over the finer details of the music while still sounding spot on natural.

An important note is the components were designed from scratch around new JJ tubes (and Tung Sol
output tubes are even better), and not designed around NOS and/or DHT tubes.

cheers

steve

ps. I rewrote for hopefully clearer, easier understanding.






 

[steve]

Although I posted this before, one of the least appreciated aspects of audio is to
make sure the speaker wires are properly tightened at the amplifier jacks and speaker jacks.

Of course don't strip the threads, but the contact resistance must be constant, or the
speaker damping, for each driver, will be inconsistent. Doesn't seem like much, but it
can make a difference, and does in this system.

Most system setups have contacts for each channel to deal with;
the connections at the amplifier and the connections at the speaker the most obvious.
Some may wish to solder the speaker wires to the speaker crossovers and even at the amplifier outputs.

Some very nice reference recordings to check out one's audio system is at "Music Discussion" sub forum.

"Sharing Top Notch, Reference Musical Links..."
https://www.audionervosa.com/index.php?topic=6076.0


cheers

steve

ps. Some time ago, I soldered the speaker wires to the crossover board. I am seriously considering soldering
the speaker wires directly to feed through amplifier output wires.

[steve]

One other tidbit if I may.

It is almost always advantageous to use the same brand, and even model, capacitor throughout
a design. When one has to compensate an inferior capacitor with a different
brand capacitor, the end result is almost always degraded sound in one or more aspects.

Using the same brand, the most natural/accurate capacitors in a design results in fewer abnormal
aspects in sound. Of course, the budget needs to be considered.

As an example, adding a single 1ufd solen capacitor into the crossover network negatively affected
the sound of the entire system.

One outstanding, natural, accurate capacitor, in absolute terms, is the Mundorf M EVO aluminum,
in oil (white covering). Small to large values I have tested are outstanding and recommended.
(I am not affiliated, and/or compensated in any way from Mundorf.)
 
cheers

steve