[Niteshade]

The best kind of upgrades are ones that are not controversial.
As a result, I rarely suggest component upgrades such as capacitors, kinds of wire, binding posts, etc..

The best upgrades are circuit based. In my opinion, component upgrades should be avoided because, for example, going from a .22uf XYZ to a .22uf ABC will not make a difference if they are both the same grade. If the grade of components used exceeds the circuit's specifications, then there is no need to replace it.

An upgrade should be defined by a easily identified performance improvement. My favorite upgrade for all Niteshade amps is our DC filament package. What's so special about it? It's one of the few upgrades that dramatically improves sound quality and is not in the audio signal's path! This is what I call an ideal upgrade. It works by cleaning up the audio circuit's operating environment. Tube filaments are traditionally ran off of AC. Alternating current by nature can be picked up by nearby metal objects. By using DC to run tube filaments, a quiet backdrop changes to a near perfectly black backdrop. More detail surfaces within music. We want to hear subtle details, in the milliwatt range while listening to well recorded songs. A black backdrop is the best way to surface detail with a tube amplifier.

The other way is a continually variable feedback loop. This is a standard feature on all Niteshade amplifiers. Too much or too little feedback will create synergy issues. There are thousands of speaker types being used. How is an amp going to work with a fixed feedback loop? They are set up to comply with fairly severe impedance curves. In another words, I have found them to learn towards over-compensating. This actually works fairly well, but the result is often a syrupy, overly warm or sterile sounding amp. Along with that baggage, the amp is slowed down due to a very active loop that's always behind the times. It's a law of physics that outputs come after inputs, so a delay exists if a loop is formed between the two. When you have the ability to control that loop, it goes a long way towards making a sound system perform much better. (Variable feedback used to be optional. It is now standard equipment.)

I will have more information on our upgrade options & circuit abilities later!

[jtwrace]

If it's so good why not make it standard?  It can't be that expensive.  Right?

[JohnR]

If feedback loops were as "slow" as you say they are, then they wouldn't work at all... All that aside, how would the end user know where the correct setting is?

[Niteshade]

DC filaments are standard on all preamps now.

An amp without this upgrade works very well. My equipment is extremely quiet, so it is not necessary for normal operation. However, for those wanting to make something good even better...here is an affordable way to do it.

[jtwrace]

DC filaments are standard on all preamps now.

Then it's not an upgrade.  If the preamp was called NSPre then you did this as a production upgrade it could be the NSPre.1 or some sort of name change.  Right?

[Niteshade]

Feedback loops have lag, it is inevitable. That lag has to have inhospitable consequences. They are minute in most cases.

The feedback control is set where the best sound is obtained. While a song is playing, the feedback can be adjusted to where it sounds best. Measurements do not have to be taken and there is no way to damage the amp if it's turned up too high. A very high setting will result in a muffled or totally cancelled (no sound) output.

[Niteshade]

That's right. It was an upgrade at one time. I made it standard because the benefits were so great. This upgrade brought the preamp line up to the next level of performance. I didn't bother changing the name.

Then it's not an upgrade.  If the preamp was called NSPre then you did this as a production upgrade it could be the NSPre.1 or some sort of name change.  Right?

[JohnR]

I give up.

[bunky]

I dont think that electrical engineers are taught in school that resistors,capacitors or tubes impart a sonic signature when they are employed in a audio circuit.if a textbook does not say that there are sonic differences between electical components with the same ratings when used in a audio circuit does not mean that these differences do not exist .if something cannot be measured using known methods does not mean that it cannot exist.for example capacitors can make a difference even in a excellent circuit.i used to own a BAT VK60 tube power amplifier which sounded very good in stock form. i replaced the factory installed .22uf Jensen PIO coupling capacitors with .22 V-cap TFTF capacitors in thier place and after a rather long break in period the amp went from very good sonics to stellar sonics. yes the V-caps are very exspensive but in a well designed circuit the sonic improvement can be well worth the cost of the upgraded capacitors.thanks....WCW III

[JohnR]

I think I fell into a rabbit hole. What does capacitors have to do with lag in a feedback circuit?

[bunky]

I think I fell into a rabbit hole. What does capacitors have to do with lag in a feedback circuit?

Hey John,my comments are in response to Blair's comments regarding capacitors as a upgrade at the start of this thread and had nothing to do with feedback circuits 

[BobRex]

It's somewhat ironic that while Blair, as a relatively new manufacturer, claims that there is no difference between say, a polyester cap and a teflon cap (assuming the same value), other, more established manufacturers (Audio Research, conrad johnson, Audio Note, hell, even B&W has discovered the sonic advantages to Mundor caps) have been converting to better components.  So who is right? 

Yes, there are others who share Blair's philosphy - Frank Van Alstine and Roger M. come to mind, but again, they are niche manufacturers (granted, very well rgarded niche manufacturers) who more than likely don't have have either the time,inclination, or cost incentive to play the component game (some of these suckers can get expensive!)  Although I seem to recall that Jeff Behr has modified Rogers EM7 amps with positive results.

That B&W has done the research and concluded that the Mundorf oil caps are sonically the best for their diamond tweeters is enough for me to accept that here are sonic differences between components. 

So to me it boils down to these questions: 
1) Blair, why do you beleive that components don't make a sonic difference? 
2) Have you experimented with the exotics?
3) Is it possible that some circuits are more sensitive to upgrades than others?
4) Are all the other rather large and successful manufacturers spewing marketing bullsh*t?
5) Are all of the field reports  delusional?
6) Does anybody really know what time it is?

[bigjppop]

I'm not normally one to jump in on stuff like this, but just wanted to add that just because some well known manufacturers are using exotic components does not make those components better.  Good business people give their customers what they want.  If customers demand something, ie exotic components, a good business person is going to give them what they want.  When you start to get into the megabuck stuff like B&W's Diamond line, those companies almost can't compete without exotic parts.  Customers that are dropping 10K on speakers (or more) want to know they're getting "something" for their money.

Anyway, not making a judgement call one way or the other on the sonic properties of anything, just saying...

It's somewhat ironic that while Blair, as a relatively new manufacturer, claims that there is no difference between say, a polyester cap and a teflon cap (assuming the same value), other, more established manufacturers (Audio Research, conrad johnson, Audio Note, hell, even B&W has discovered the sonic advantages to Mundor caps) have been converting to better components.  So who is right? 

Yes, there are others who share Blair's philosphy - Frank Van Alstine and Roger M. come to mind, but again, they are niche manufacturers (granted, very well rgarded niche manufacturers) who more than likely don't have have either the time,inclination, or cost incentive to play the component game (some of these suckers can get expensive!)  Although I seem to recall that Jeff Behr has modified Rogers EM7 amps with positive results.

That B&W has done the research and concluded that the Mundorf oil caps are sonically the best for their diamond tweeters is enough for me to accept that here are sonic differences between components. 

So to me it boils down to these questions: 
1) Blair, why do you beleive that components don't make a sonic difference? 
2) Have you experimented with the exotics?
3) Is it possible that some circuits are more sensitive to upgrades than others?
4) Are all the other rather large and successful manufacturers spewing marketing bullsh*t?
5) Are all of the field reports  delusional?
6) Does anybody really know what time it is?

[bunky]

It's somewhat ironic that while Blair, as a relatively new manufacturer, claims that there is no difference between say, a polyester cap and a teflon cap (assuming the same value), other, more established manufacturers (Audio Research, conrad johnson, Audio Note, hell, even B&W has discovered the sonic advantages to Mundor caps) have been converting to better components.  So who is right? 

Yes, there are others who share Blair's philosphy - Frank Van Alstine and Roger M. come to mind, but again, they are niche manufacturers (granted, very well rgarded niche manufacturers) who more than likely don't have have either the time,inclination, or cost incentive to play the component game (some of these suckers can get expensive!)  Although I seem to recall that Jeff Behr has modified Rogers EM7 amps with positive results.

That B&W has done the research and concluded that the Mundorf oil caps are sonically the best for their diamond tweeters is enough for me to accept that here are sonic differences between components. 

So to me it boils down to these questions: 
1) Blair, why do you beleive that components don't make a sonic difference? 
2) Have you experimented with the exotics?
3) Is it possible that some circuits are more sensitive to upgrades than others?
4) Are all the other rather large and successful manufacturers spewing marketing bullsh*t?
5) Are all of the field reports  delusional?
6) Does anybody really know what time it is?

I believe that Blair knows exactly what he is doing otherwise i would not consider being a customer and would never have ordered a tube amplifier from him. the blanket dismissal of capacitors as a upgrade path is what led to my response to Blairs comments.i wanted to share a 1st hand experience i had with exotic capacitors....WCW III

[saisunil]

Cap rolling makes difference just like tube rolling ...
So does moving off of AC to DC
 
Of course the key is the base circuit implementation ...
Which tweak / upgrade is better than the other is so implementation dependant ... some circuits (for some reason or the other) are less sensitive to upgrades / changes than others ...
 
Whatever works ...

[bunky]

Feedback loops have lag, it is inevitable. That lag has to have inhospitable consequences. They are minute in most cases.

The feedback control is set where the best sound is obtained. While a song is playing, the feedback can be adjusted to where it sounds best. Measurements do not have to be taken and there is no way to damage the amp if it's turned up too high. A very high setting will result in a muffled or totally cancelled (no sound) output.

i used to own a TAD 60 tube amplifier that had variable feedback via a knob on top of the unit.i liked the feature as it allowed me to fine tune the sound to my particular system 

[BobRex]

I believe that Blair knows exactly what he is doing otherwise i would not consider being a customer and would never have ordered a tube amplifier from him. the blanket dismissal of capacitors as a upgrade path is what led to my response to Blairs comments.i wanted to share a 1st hand experience i had with exotic capacitors....WCW III

I never said Blair doesn't know what he is doing, nor would I say the same for Frank and Roger.  My point is that I don't know if Blair's decision is based upon textbook or practical experience.  Engineering textbooks only go so far - for instance, college texts will talk about circuit behavior, but they rarely mention sonics.  As such, the sonic impact of different capacitor dissipation factors is a non starter.  Does that mean the effect doesnt exist?

That you, Bunky, found a difference in upgrading caps should tell you that maybe Blair has the TECHNICAL knowledge, but that maybe his POV suffers from dogma.  After all, I would never say that Vicktor K. doesn't know what he is doing, but you decided that his component choice could be improved upon, AT A PRICE. 

Blair made a wide ranging statement, one that apparently doesn't hold true for others, either experimentors or designers.  Does that mean that one knows exactly what they are doing and the others don't.  Or does it mean that differing priorities enter into the picture?  Or does it mean that experiences should be shared and everyone learn from it?

[Ericus Rex]

Yes, there are others who share Blair's philosphy - Frank Van Alstine and Roger M. come to mind, but again, they are niche manufacturers (granted, very well rgarded niche manufacturers) who more than likely don't have have either the time,inclination, or cost incentive to play the component game (some of these suckers can get expensive!)

I'm not so sure about that.  Roger's RM-9 has Wondercaps as the coupling caps.  For 1985 (or whatever year mine was made) that was THE premium cap.  The caps outside of the signal path are standard electros.  It would seem that Roger accepts that they effect the sound but doesn't stupidly put them were they make no difference.

[bunky]

Formal education lays a very important foundation but there is no substitute for real world experience. i have learned much more from listening to gear and from advice from folks with tastes similar to my own than i have looking at specifications or technical manuals. I respect Blairs opinions but that in no way means that agree with his opinions on the sonic effect of different brands of capacitors in a given audio circuit....WCW III

[Niteshade]

I'll go into this further- but for now I want to make sure people read this part of my original post:

"...for example, going from a .22uf XYZ to a .22uf ABC will not make a difference if they are both the same grade. If the grade of components used exceeds the circuit's specifications, then there is no need to replace it. "

Two points are being made:

1. Both components are the same quality
2. Both components exceed the requirements of the circuit

It is worth it to upgrade components if you're going from inferior to superior components. I never said that it was not. What I am saying is this: IF the original components are high quality AND exceed the circuit's requirements for quality, I would advise against a so-called upgrade.

The point of an upgrade is to improve something. You really can't improve anything if the best component for the job is already installed.

There are different components for different jobs. For example, there are multiple 2uf capacitors and multiple 10 ohm resistors. They will read exactly the same on a tester (that is, 2uf or 10 ohms) but will be designed for different jobs. With that in mind, I know the difference between component types based on their construction materials and where they were intended to be used. In a nutshell, the capacity and voltage ratings are just a couple of specifications out of several. The same goes for other electrical components.

I will go through the thread closer tomorrow morning. There's too much to digest after a nice plate a BBQ ribs, a salad and some bean soup!