[medium jim]

One must first realize, that perfection itself does not exist, to then understand, that it can never be reproduced...

Wow, pretty astute

Jim

[bside123]

A few years back, I was listening to a Live Cream LP. It didn't sound so good, as a matter of fact, it sounded like kaka. So I began struggling with my system's synergy. I went on a rampage. I changed my cartridge, changed out the tonearm, bought a new turntable, went back and forth between tube and SS amps. I tried both active and passive preamps, experimented with every possible combination of metals in my interconnects and speaker wires. I shortened the signal path of every wire. Hardwired for sure. Acoustic treatments, power conditioning and speaker placement were to no avail, as I changed between ported, 3-way, 2-way, boxed, open baffled and full-range drivers. The Cream just didn't sound "live" in my listening room, and I got really crapped out. I thought the only way I'd be happy hearing these tracks was to actually hear the band live. Live Cream.

So, I came up with a this great idea. I called up Eric Clapton and asked if he'd get the ol' chaps together, fly out to my crib in the sticks, set up in my living room and give me a private concert. 'Course, amicable bloke that he is, Eric arranged for everything mind you, and the following weekend, the first reunion of the Cream was at my house... Live. No shit. This was before the famed Albert Hall Reunion. That's how they got the idea to get back together.

Well, the power trio set up and started playing, but soon into, "Strange brew... look what's inside of you," I stopped the show. It sounded horrible! At first I couldn't figure out why. When I attempted to question the band about it, that's when all hell broke loose.

This began a protracted and extremely heated argument between me, Eric, Ginger and Jack. I didn't like the setting that Eric was using on his Vintage Fender Deluxe Amp. He was incensed when I told him he might want to consider different tubes and that his tone was a little thin. Then me and Jack Bruce got into it about the capacitance of the wiring on the active pickups on his bass, and whether or not his stack of 4 X 12 cabinets was just too much bass for the room. Besides all of that, Ginger Baker was using old heads on the drums and the Zildjan crash cymbal didn't have the right decay. It sounded too "tizzy."

They played a couple of more numbers, until I lost my patience and told them all to get out. Live Cream sounded like crap. 'Matter of fact, it sounded worse than the record, and this stint cost me a whole lot more money than I'd care to admit to paying.

Since then, I've just tossed albums on to the record player, and I'm done with it. NCore, Peace Corps or Live... don't matter, you can't always get what you want. You can try sometime, and you just might find..."

Oh, remind me sometime to tell you my Rolling Stones story. 

[OzarkTom]

One must first realize, that perfection itself does not exist, to then understand, that it can never be reproduced...

But it is fun trying, that is what this hobby is all about.

[OzarkTom]

Ozark the link has a virus!  Just stopped by Avast

That is odd, everytime I click on it, it works for me.

Paul says:

Volume controls

Well, this is a fine hornet’s nest I’ve gotten into.  Half of you seem to think I live in a cave and haven’t any clue what high-end audio is all about and the other half think I have it right – and then yet another half think I am opening Pandora’s box and letting all the digital nasties out to seek and destroy all of analog.  Wait a minute, how many halves are there?
 
For the record (and not to make a pun) I love analog, have been designing analog circuits for over 40 years, continue to do so and near the end of this series will be advocating a hybrid approach as part of the new paradigm I am advocating that plays nice with both analog and digital.  So, deep breath my friends, I am not out to kick your dog or put a damper on your analog dreams and I hope we can simply enjoy these posts in the spirit they are written, fun and informative – forward looking.  I really am on your side and the side of great music and audio.  Really. 
 
One of the core elements of any preamplifier is the volume control – without it you cannot adjust the level of what you’re playing and the system becomes rather useless.  Let’s talk analog volume controls today.
 
There are 50 ways to Sunday to build an analog volume control and I think I may have tried and listened to every single one.
 
In its simplest classic form most analog preamplifier volume controls are but a simple variable resistor or potentiometer (called a “pot” for short).  How do these work?  They are simple mechanical devices that have a long strip of resistive material with a connection on each end of the strip.  One of these two connections (A) is attached to the audio source and the other side (B) is connected to ground (zero audio).
 
A third contact (W) is pressed against this strip and connected to a knob or a lever so that the user can move the contact up and down the length of the resistive strip.  This contact becomes the output of the volume control.  By placing the contact on a different area of the strip you get different volume levels out – louder when you move towards A and softer as you move towards B.  Put two strips together with two contacts moving together and you have a dual potentiometer or – a stereo pot.  Move either one of the two contacts differently and you adjust the left and right channels differently – thus making a balance control.
 




Remembering that all types of resistors sound different when used in the signal path, it should be no surprise that the quality of the music running through one of these pots is very much dependent on the quality of the resistive element, the contacts and the way it’s implemented.  In fact, there is no such thing as a neutral or transparent sounding pot or volume control.
 
The fact that any form of volume control has a negative effect on the sound is a really important concept to grasp.  Switched attenuators, Gain Cells, pots, electronic attenuators, CMOS switches, photo cells and every scheme imaginable to change the volume has a negative affect on the sound.  The challenge is to figure out how to do as little damage to the sound as possible and there are many schemes out there – ranging from the absurd to the lame and cheap and everything in between.
 
The point I want to make in today’s post is that the volume and balance controls in an analog preamp all suck to some degree.  We have to accept that we cannot change the volume without affecting the sound.
 
Lastly I want to give you a piece of advice when it comes to volume controls.  Less is more.  By that I mean the higher the volume control level the better it sounds because less of the resistor is in the signal path.  Look at the drawing I included – if the W connection is tied right to the audio input A (full volume), then essentially there is nothing in the signal path to damage the music.  The farther away W gets from A (turning the level down), the more sonic damage is done.  Less is more.
 
I wrote about this nearly a year ago in a post labeled Step on the gas and I think it’s not only worth repeating but it also leads us to tomorrow’s post about digital volume controls.
 
Interesting how in both cases, less is more when it comes to volume controls.

[bhakti]

Not a cool aid drinker, but like cool aid!

Just responding to the op.  I'm not a big fan of ss amps, but I like these so far.  They are shape shifters - so beware!  Simple plug and play into your system may not reveal the amps capability.  They may be better than I originally thought.  Chasing ghosts   

[DaveC113]

That is odd, everytime I click on it, it works for me.

Paul says:

Volume controls

Well, this is a fine hornet’s nest I’ve gotten into.  Half of you seem to think I live in a cave and haven’t any clue what high-end audio is all about and the other half think I have it right – and then yet another half think I am opening Pandora’s box and letting all the digital nasties out to seek and destroy all of analog.  Wait a minute, how many halves are there?
 
For the record (and not to make a pun) I love analog, have been designing analog circuits for over 40 years, continue to do so and near the end of this series will be advocating a hybrid approach as part of the new paradigm I am advocating that plays nice with both analog and digital.  So, deep breath my friends, I am not out to kick your dog or put a damper on your analog dreams and I hope we can simply enjoy these posts in the spirit they are written, fun and informative – forward looking.  I really am on your side and the side of great music and audio.  Really. 
 
One of the core elements of any preamplifier is the volume control – without it you cannot adjust the level of what you’re playing and the system becomes rather useless.  Let’s talk analog volume controls today.
 
There are 50 ways to Sunday to build an analog volume control and I think I may have tried and listened to every single one.
 
In its simplest classic form most analog preamplifier volume controls are but a simple variable resistor or potentiometer (called a “pot” for short).  How do these work?  They are simple mechanical devices that have a long strip of resistive material with a connection on each end of the strip.  One of these two connections (A) is attached to the audio source and the other side (B) is connected to ground (zero audio).
 
A third contact (W) is pressed against this strip and connected to a knob or a lever so that the user can move the contact up and down the length of the resistive strip.  This contact becomes the output of the volume control.  By placing the contact on a different area of the strip you get different volume levels out – louder when you move towards A and softer as you move towards B.  Put two strips together with two contacts moving together and you have a dual potentiometer or – a stereo pot.  Move either one of the two contacts differently and you adjust the left and right channels differently – thus making a balance control.
 




Remembering that all types of resistors sound different when used in the signal path, it should be no surprise that the quality of the music running through one of these pots is very much dependent on the quality of the resistive element, the contacts and the way it’s implemented.  In fact, there is no such thing as a neutral or transparent sounding pot or volume control.
 
The fact that any form of volume control has a negative effect on the sound is a really important concept to grasp.  Switched attenuators, Gain Cells, pots, electronic attenuators, CMOS switches, photo cells and every scheme imaginable to change the volume has a negative affect on the sound.  The challenge is to figure out how to do as little damage to the sound as possible and there are many schemes out there – ranging from the absurd to the lame and cheap and everything in between.
 
The point I want to make in today’s post is that the volume and balance controls in an analog preamp all suck to some degree.  We have to accept that we cannot change the volume without affecting the sound.
 
Lastly I want to give you a piece of advice when it comes to volume controls.  Less is more.  By that I mean the higher the volume control level the better it sounds because less of the resistor is in the signal path.  Look at the drawing I included – if the W connection is tied right to the audio input A (full volume), then essentially there is nothing in the signal path to damage the music.  The farther away W gets from A (turning the level down), the more sonic damage is done.  Less is more.
 
I wrote about this nearly a year ago in a post labeled Step on the gas and I think it’s not only worth repeating but it also leads us to tomorrow’s post about digital volume controls.
 
Interesting how in both cases, less is more when it comes to volume controls.

Sounds like a setup for pushing digital volume controls. 

[JohnR]

Ozark the link has a virus!  Just stopped by Avast

Google is showing warnings on coming to this page, which is a bit stupid since it's a link, whatever the problem is WE don't have it. Anyway, it's been modified, for now at least.

[medium jim]

Sounds like a setup for pushing digital volume controls. 

+1

Jim

[Freo-1]

Everyone here is a fanboy!!! Just deal with it.
Cab and Rclark love NCore
Tyson is 100% bias against SS
Fero loves class A
Sts9fans is pretty much a Pass fanboy, anti tubes and pro class A.
How do you deal with it? Just tune them out. Would I ever put any weight behind a Tyson amp review? Never.
Would I ever listen to RClark without doing my own research? Hells no.
Am I going to try Ncore? Maybe.
Where's the Koolaid?

Asile 3, middle shelf.   
 
BTW, I'm partial to Pass designed Class A, thank you.     ( Some tubed based Class A as well).

[medium jim]

This has turned into a political debate, I'm a Bottlehead...I'm SS....I'm Class D all the way...and the betweeners...

It's pretty obvious that there will never be a winner in this debate as 99% of us have already made up our minds as the years have weened and leaned us to a path of certainty (for ourselves).  The only way to learn is through the trial and error process and hope for the best. 

My livelihood is in vintage, rare and otherwise used guitars and for me there has been a paradigm shift towards new guitars that replicate guitars from the golden era....Pre-war for Acoustics and the 50's for electrics.   

While I still love old guitars, the newer ones are built better, sound better and play easier.  I suppose the same will happen with Audio Gear.  That said, I really feel that as far as tube amplification goes, they got it right a long, long, time ago and it is at its pinnacle and has been for well over 50 years.

I hope I live long enough to see if something does come along that will blow me away again, but frankly, I haven't been blown away in many a year.

Jim

[OzarkTom]

Paul sez today on preamps:

Trying to put the genie back in the bottle

So if the days of the analog preamp are numbered because the number of analog sources for it to control are diminishing and if digital preamplifiers really haven’t appeared on the scene in any numbers and have a long way to go before they are accepted as musically satisfying enough, what’s a music lover to do for control?
 
For many of us nothing: what we have is just fine, thank you.  But, if you’re anything like me, it’s unsettling to know that inserting an extra piece of gear in the signal path is giving me less than what’s there.  It’s kind of like being comfortable with your daily drive through the backroads of the city to get to work – it’s been your route for many years – and then to discover the city just completed a straight-shot thoroughfare that cuts the drive time in half.  The first time you take the shorter path it’s clearly faster, better and makes more sense – but the old drive was prettier, had more charm, wasn’t all that bad and in fact you miss it.
 
Problem is, every time you’re driving on the old road you are now painfully aware you are taking extra unnecessary steps and those steps are now cutting into your day – and your formerly pleasant drive will simply never be the same.  It’ll never be the same because now you have tasted something better.
 
In our sound room we have a PerfectWave DAC/Bridge setup feeding our power amplifier directly through a long set of XLR cables.  All the sources are plugged into the PWD.  But we also have one of our analog preamps in the sound room as well.  Why is it there?  For testing.
 
Let’s say we want to compare our PWD to another manufacturer’s DAC and their DAC doesn’t have the ability to act as a preamp – or we want to narrow down the comparison to just the DACS themselves. In that case we have to plug both DACS into the analog preamp and then move the long XLR cables feeding the power amp to the output of the preamp.  This process always depresses me – I put it off forever – sometimes never doing it.  Why?  Because the first thing I have to do is adjust to the sound of the system all over again.  It doesn’t sound anywhere near as clean, open and spacious with the preamp in the path.  I simply don’t feel like I am doing justice to the music anymore and then how do you make a decision with impure audio?  It’s kind of like choosing between two really bad politicians running for the same race.  It just sucks.
 
OK, I am done venting.  Tomorrow let’s talk about Paul’s solution to the preamp problem.

[jtwrace]

What does Paul have to do with this thread?  How about starting a Paul thread in the commercial zone?

[OzarkTom]

What does Paul have to do with this thread?  How about starting a Paul thread in the commercial zone?

I am hoping that Hypex(Bruno) will decide to come out with an all digital amp with built-in Dac, that's all. Since Bruno is on top of his game, he can help to further improve the sound by getting rid of preamps. Preamps have been dead for the last 25 years, IMHO.

[jtwrace]

I am hoping that Hypex(Bruno) will decide to come out with an all digital amp with built-in Dac, that's all. Since Bruno is on top of his game, he can help to further improve the sound by getting rid of preamps. Preamps have been dead for the last 25 years, IMHO.

I see.  Well, maybe Bruno can respond. 

[munosmario]

I am hoping that Hypex(Bruno) will decide to come out with an all digital amp with built-in Dac, that's all. Since Bruno is on top of his game, he can help to further improve the sound by getting rid of preamps. Preamps have been dead for the last 25 years, IMHO.

OzarkTom, unfortunately, and never mind being at “the top of his game”, it appears Bruno is moving in opposite direction to your wish. Under his other company named Mola-Mola, a sister company to Hypex, Bruno just launched (at a Munich high-end show) an Euro 10,000 Preamp that includes a DAC. This Pre/DAC is intended as a matching unit to his EURO 10,000 (per pair) monoblocks that he has specifically designed to showcase his Ncore technology. 

Notice that, reportedly, these correspond to Bruno’s current best efforts. This is Bruno himself designing and marketing/selling through a company of his own, not the efforts of a third party "luxury" high-end audio company using his modules. Incidentally, it makes one wonder right away how much real SQ value has Bruno added into his Euro 10,000 rendition of a pair of monoblocks, in particular, aside of just more power, when compared to a DIY rendition--at 1/10th of that price--of a pair of monoblocks using NC400 modules.  How high was the bar set before and how higher is he actually setting it now?

Mario

[jmbulg]

OzarkTom, unfortunately, and never mind being at “the top of his game”, it appears Bruno is moving in opposite direction to your wish. Under his other company named Mola-Mola, a sister company to Hypex, Bruno just launched (at a Munich high-end show) an Euro 10,000 Preamp that includes a DAC. This Pre/DAC is intended as a matching unit to his EURO 10,000 (per pair) monoblocks that he has specifically designed to showcase his Ncore technology. 

Notice that, reportedly, these correspond to Bruno’s current best efforts. This is Bruno himself designing and marketing/selling through a company of his own, not the efforts of a third party "luxury" high-end audio company using his modules. Incidentally, it makes one wonder right away how much real SQ value has Bruno added into his Euro 10,000 rendition of a pair of monoblocks, in particular, aside of just more power, when compared to a DIY rendition--at 1/10th of that price--of a pair of monoblocks using NC400 modules.  How high was the bar set before and how higher is he actually setting it now?

Mario

Some partial answers:

http://www.diyaudio.com/forums/vendors-bazaar/190434-hypex-ncore-196.html#post2898572

http://www.diyaudio.com/forums/vendors-bazaar/190434-hypex-ncore-9.html#post2608169

[DaveC113]

Paul sez today on preamps:

Trying to put the genie back in the bottle

So if the days of the analog preamp are numbered because the number of analog sources for it to control are diminishing and if digital preamplifiers really haven’t appeared on the scene in any numbers and have a long way to go before they are accepted as musically satisfying enough, what’s a music lover to do for control?
 
For many of us nothing: what we have is just fine, thank you.  But, if you’re anything like me, it’s unsettling to know that inserting an extra piece of gear in the signal path is giving me less than what’s there.  It’s kind of like being comfortable with your daily drive through the backroads of the city to get to work – it’s been your route for many years – and then to discover the city just completed a straight-shot thoroughfare that cuts the drive time in half.  The first time you take the shorter path it’s clearly faster, better and makes more sense – but the old drive was prettier, had more charm, wasn’t all that bad and in fact you miss it.
 
Problem is, every time you’re driving on the old road you are now painfully aware you are taking extra unnecessary steps and those steps are now cutting into your day – and your formerly pleasant drive will simply never be the same.  It’ll never be the same because now you have tasted something better.
 
In our sound room we have a PerfectWave DAC/Bridge setup feeding our power amplifier directly through a long set of XLR cables.  All the sources are plugged into the PWD.  But we also have one of our analog preamps in the sound room as well.  Why is it there?  For testing.
 
Let’s say we want to compare our PWD to another manufacturer’s DAC and their DAC doesn’t have the ability to act as a preamp – or we want to narrow down the comparison to just the DACS themselves. In that case we have to plug both DACS into the analog preamp and then move the long XLR cables feeding the power amp to the output of the preamp.  This process always depresses me – I put it off forever – sometimes never doing it.  Why?  Because the first thing I have to do is adjust to the sound of the system all over again.  It doesn’t sound anywhere near as clean, open and spacious with the preamp in the path.  I simply don’t feel like I am doing justice to the music anymore and then how do you make a decision with impure audio?  It’s kind of like choosing between two really bad politicians running for the same race.  It just sucks.
 
OK, I am done venting.  Tomorrow let’s talk about Paul’s solution to the preamp problem.

It seems to me that Paul has an amp with more gain than needed and a poor sounding preamp. The point of a preamp is voltage gain, not just volume control, and the power amp current gain. It also doesn't make sense to put switching and volume controls in a hot chassis with high currents. And, it is best for the voltage gain to have it's own power supply, integrated amps rarely if ever do this.

[Don_S]

Curious minds (mine) needed to know.

On August 5th, 2012 the exchange rate is 1 EUR = 0.8055 USD.

10,000 EUR = 12415.1425 USD

[doug s.]

Paul sez today on preamps:

Trying to put the genie back in the bottle

So if the days of the analog preamp are numbered because the number of analog sources for it to control are diminishing and if digital preamplifiers really haven’t appeared on the scene in any numbers and have a long way to go before they are accepted as musically satisfying enough, what’s a music lover to do for control?
 
For many of us nothing: what we have is just fine, thank you.  But, if you’re anything like me, it’s unsettling to know that inserting an extra piece of gear in the signal path is giving me less than what’s there.  It’s kind of like being comfortable with your daily drive through the backroads of the city to get to work – it’s been your route for many years – and then to discover the city just completed a straight-shot thoroughfare that cuts the drive time in half.  The first time you take the shorter path it’s clearly faster, better and makes more sense – but the old drive was prettier, had more charm, wasn’t all that bad and in fact you miss it.
 
Problem is, every time you’re driving on the old road you are now painfully aware you are taking extra unnecessary steps and those steps are now cutting into your day – and your formerly pleasant drive will simply never be the same.  It’ll never be the same because now you have tasted something better.
 
In our sound room we have a PerfectWave DAC/Bridge setup feeding our power amplifier directly through a long set of XLR cables.  All the sources are plugged into the PWD.  But we also have one of our analog preamps in the sound room as well.  Why is it there?  For testing.
 
Let’s say we want to compare our PWD to another manufacturer’s DAC and their DAC doesn’t have the ability to act as a preamp – or we want to narrow down the comparison to just the DACS themselves. In that case we have to plug both DACS into the analog preamp and then move the long XLR cables feeding the power amp to the output of the preamp.  This process always depresses me – I put it off forever – sometimes never doing it.  Why?  Because the first thing I have to do is adjust to the sound of the system all over again.  It doesn’t sound anywhere near as clean, open and spacious with the preamp in the path.  I simply don’t feel like I am doing justice to the music anymore and then how do you make a decision with impure audio?  It’s kind of like choosing between two really bad politicians running for the same race.  It just sucks.
 
OK, I am done venting.  Tomorrow let’s talk about Paul’s solution to the preamp problem.

what a load of b$  paul (or you?) obviously don't have a good preamp.  and the analogy is not a good analogy.  are you trying to get through the listening session as quickly as possible?    

a better analogy would be the new road that takes you the same amount of time, but also has much nicer scenery.  i.e.: using a quality preamp instead of doing w/o. 

ymmv,

doug s.

[James Romeyn]

I am hoping that Hypex(Bruno) will decide to come out with an all digital amp with built-in Dac, that's all. Since Bruno is on top of his game, he can help to further improve the sound by getting rid of preamps. Preamps have been dead for the last 25 years, IMHO.

Dan Wright played his prototype DAC/preamp at 2012 CES, fantastic looks and performance among the top five @ CES, not hindered by his best stereo amp and $30k worth of AudioMachina speakers (cabinets carved from solid aluminum with I presume only one removable panel being the rear, Scan Speak's best drivers, first order crossovers).  Dan said the best feature of a one-piece DAC/preamp is deleting one complete gain stage compared to separate DAC/separate preamp.