[werd]

That post above by Wayne1..... thats what you call audio poetry. thats good stuff..... 

[Mudslide]

...uuum, if you want to take my name in vain, at least get the spelling correct....it's FALLER 


That said, I'm staying clear of this A/B DBT conversation....I know better. 

My apologies Mr. Faller.  I was rushed when I posted.

Let me say that I liked your article, found it very interesting, and appreciated the very careful and detailed steps you took to evaluate the gear.  I thought you did an outstanding job of testing and reporting.  My point in bringing it up was not to disparage what you had to say (or the testing you did), but to point out that when all variables are not controlled, truth cannot be verified.  And as you (approximately) said yourself at one point, "99% of listeners won't hear a difference". 

To be honest, I hesitated before entering this A/B-DBT fray, myself.  But I find that there is a bit of larceny in our hobby (not from you), and certainly unfettered biases are sometimes being stated as fact (you didn't).  There is also the component of "common sense" in the audio hobby that something should be true (which affects people's purchasing decisions)...but in fact isn't. 

[eclein]

Maybe..I missed something, I thought we were just talking about different components and our perceived importance of them. I was certainly in no way trying to persuade anyone's buying decision.
**If your reading this post with a buying decision pending, please consider that I was only commenting on what I heard**
Jim-I hope you get a chance to do your test as I think it would be very cool to see how it turns out.

Exit -stage right!!!....>>>>

[cacophony777]

Why do you think some people prefer battery power systems over AC. It is not because batteries are "better". It is because they are isolating their system from all the switching noise being shoved into their lines from all the little wall warts. Again, try unplugging a few and see if it sounds better.

Jim,

For a secondary blind test, you could have:

* Audio setup with Squeezebox that has linear power supply hooked up to power strip A

* A bunch of RFI emitting, AC polluting devices hooked up to power strip B (on the same circuit as power strip A)

Then just turn power strip B on/off to do the A/B switch!

[billmcc]

I see a bit of discussion about changing out PS's to upgraded ones to help with SQ and noise reduction. It makes senes to me and if I had a Squeeze Box or streamed music from my PC I would definitely try it.

A question I have which might not be for this thread but I will give it a shot. I have my system in my livingroom which has its own 15 amp breaker. I have had several tube preamps (Rogue Audio Perseus and TAD TADAC) and I had a problem with hum. I tried all the usual fixes such as disconnecting my cable TV feed and cheater plugs but still had the hum. Is there a way to get a clean AC feed for my livingroom circuit? Are there circuit breakers or any other devices that are specifically designed to generate clean AC? I have some of my components plugged into a Panamax 5100EX and my amp, 886, CD player and Parasound 2100 plugged into a PS Audio Duet.

Any suggestions would be appreciated

Bill

 

[eclein]

Bill- I'm not 100% sure but whenever I was around anything with tubes there would be some tube noise. I played with a guitarist who had like these big tube amps and when he wasn't playing you could still hear tube noise. When I put my Tube-ed DAC into my setup I heard that all too familiar sound again. I have accepted the fact that I get some tube hum, if its fixable I'd be interested in knowing how also.
 

[Scott F.]

My apologies Mr. Faller.  I was rushed when I posted.

No worries, just poking a bit of fun 

Let me say that I liked your article, found it very interesting, and appreciated the very careful and detailed steps you took to evaluate the gear. 

Thanks for the kind words.

And as you (approximately) said yourself at one point, "99% of listeners won't hear a difference". 

Let's make sure people take what I typed in context;

I feel the need to point out the obvious. 99% of the populous won't be able to hear the difference between the switching and the linear power supplies because their systems don't have sufficient resolution for the switching power supplies artifacts to be heard. It's only when you get into the high end realm of audio do the differences become clearly audible. This is no different than when you get into the high end realm of anything, Wines, Furs, High Definition Home Theatre, Jewelry or any market where true ‘premium' goods can be found. The differences are there but you have to develop your skills to see, hear, smell or taste a discernible difference.

What I typed [to be clear] referred to the 'general populous' meaning the average Joe and Jill on the street. Not your typical audiophile with a reasonably resolute system that possesses the ability to discern (and cares about) the audible differences between gear.

To be honest, I hesitated before entering this A/B-DBT fray, myself.  But I find that there is a bit of larceny in our hobby (not from you), and certainly unfettered biases are sometimes being stated as fact (you didn't).  There is also the component of "common sense" in audio that something should be true (which affects people's purchasing decisions)...but in fact isn't.

All I can say is try it and let your ears decide.

[jsalk]

I thought of a very simple test that would eliminate the human element from the equation.  Liberty Instruments created a software program to answer just such questions as we are considering here.  It is called AudioDiffMaker. 

As applied to this situation (different power supplies with an SB feeding an outboard DAC), you would simply unplug all cheap power supplies in the house, hook up one of the power supplies to be tested and use a professional recording application to record the analog output of the DAC unit.  You would then make the same recording with the other power supply.

Using AudioDiffMaker, you would then align the two recordings with respect to phase and gain (something the program is designed to do), subtract one from the other and see the difference.  It there was a difference, it could be attributed to the power supply.  If there was not, they had no impact on the analog audio signal.

This removes all subjective analysis.  It is simply not possible to hear differences that aren't there and you would immediately see them if there were.  The power supplies would either have an impact on the resulting audio or they would not. Very simple.

But after reading and considering all of these posts, I am having second thoughts about doing any testing at all.  It seems to me that those who did not like the results would complain about methodology or the merits of testing to begin with.

These seem to be "religious" issues and not "scientific" issues. In the end, it doesn't appear that the results would change opinions either way and could create a firestorm of debate and criticism. (There are already too many personal attacks in this thread.)

I would still like to perform the tests simply because I am curious.  But I'm starting to have real reservations about publishing results.  I just don't want to get in the middle of a "religious" debate.  I would prefer simply to build speakers and let others decide what they would like to hook up to them.

- Jim

[Wayne1]

Jim,

There are problems with using AudioDiffMaker, as well.

Here is an excerpt from a post by John Swenson :

The suggestion that all you have to do is run ADM to tell you if there is any change is only valid if the AD converter you are using is significantly better than the Touch itself. From my tests I do know the Touch has significantly less than 50ps jitter. You are going to have to look far and wide to find an AD converter that has say 5ps of jitter so you can make meaningful measurements with ADM. You simply cannot make meaningful jitter measurements of a device with 30ps of jitter with test equipment that has 100ps. The results are completely meaningless.

ADM is perfectly fine for detecting things like frequency response differences etc. But if you are making a hypothesis that some code change is somehow causing a change in jitter, and you want to use ADM to see if there is a change in the analog outs, the AD converter used HAS to have significantly lower jitter than the device under test.

Personally I CAN hear these differences. Its hard to do quick back and forth tests because it takes a minute or two to apply or remove the changes. I have not been able to do blind tests under these circumstances.

My suggestion is just to listen and make up your own mind.

[werd]

I guess i will stay in the religious camp and piece  my gear together by merit. Rather then jumping over to the scientific camp and spending most of my budget on speakers with meager amps and front end electronics...

[DMurphy]

I guess i will stay in the religious camp and piece  my gear together by merit. Rather then jumping over to the scientific camp and spending most of my budget on speakers with meager amps and front end electronics...

And in so doing you will provide yourself with a best case scenario for hearing all of the colorations in the speakers that you should have spent more on.  Not that there's anything wrong with that.....

[cacophony777]

I guess i will stay in the religious camp and piece  my gear together by merit.

If you replace "merit" with "faith" this statement makes a lot more sense 

[werd]

If you replace "merit" with "faith" this statement makes a lot more sense 

yes yes, faith in my own judgement....of course thanx....

[Nuance]

So here's a question: unless you're going to disconnect every non-linear power supply in your entire house, is it worth using a linear unit?  According to what I've gathered, you wouldn't hear the effects anyway...  Also, are you really going to disconnect every single non-linear unit in the house? 

Those devices that you recommended, Wayne: they even work with the non-linear PSU"s found in televisions?  I would imagine Televisions and Computers are major offenders, but what are we to do with something that sucks that much juice; hook them up to battery backups perhaps? 

I appreciate your advice and experience in this hobby Wayne, but implying the double blind method is not scientific is something I don't appreciate.  Dr. Toole would argue otherwise.

[Nuance]

And in so doing you will provide yourself with a best case scenario for hearing all of the colorations in the speakers that you should have spent more on.  Not that there's anything wrong with that.....

Bingo! 

Jim - don't let people like werd ruin your plans.  If you want to post the results publicly, do it.  There will always be someone who is unhappy with any result, no matter what it is.  Personally, I hope I am wrong so I can feel no shame in spending money on battery backups and linear power supplies.  But as of right now I don't think they are worth the money.

[cacophony777]

These seem to be "religious" issues and not "scientific" issues. In the end, it doesn't appear that the results would change opinions either way and could create a firestorm of debate and criticism. (There are already too many personal attacks in this thread.)

I would still like to perform the tests simply because I am curious.  But I'm starting to have real reservations about publishing results.  I just don't want to get in the middle of a "religious" debate.  I would prefer simply to build speakers and let others decide what they would like to hook up to them.

I would find the results very interesting, but I agree that it may be impossible to change people's minds in these matters. And you know what, that's alright.

So maybe just share the findings with me and Nuance   

In all seriousness, I don't foresee too much of a firestorm if the results are presented as "here are my observations...YMMV". We all hear different things after all, so as long as that's respected I would hope the discussion could remain healthy.

[floresjc]

And in so doing you will provide yourself with a best case scenario for hearing all of the colorations in the speakers that you should have spent more on.  Not that there's anything wrong with that.....

From my own personal experience, I think what werd is saying is somewhat lunacy. I think Dennis is right on the mark here. And I'll offer my experience in terms of the original post.

I felt like I had a good chance to mess with individual components and their effects, because I got the pieces of my system staggered in time after I returned from Afghanistan. Before I went with my Salk/AVA setups, my system consisted of an Outlaw 1070 receiver rated at 65wpc and AV123 Rocket 760's. Generally, my 2-channel source was the analog out from my iPod into the Outlaw, but the iPod did contain lossless files.

The first question would be, did the Rocket system sound good? I certainly thought so, as a baseline system (my first) and fairly cheap rig in the grand scheme of things, it probably sounds better than what 95% of the planet uses, which at best is normally some Sony HTIB from Best Buy. Does my Salk system (AVA Insight gear for all electronics and Salk HT2-TL/SongTowers) sound better? Unquestionably yes. And so I'll give you the 10 cent tour of what I think the differences are by component.

The first thing I got in was my Squeezebox Duet. Since I didn't have my DAC yet, I tried the analog outs. Made the Rockets sound a bit better, not night and day, but neither the iPod DAC nor the SB DAC are going to win any awards. I hooked up a Blue Jeans coax cable to the digital out and ran it through my Outlaw, which has pretty decent DACs in it. Going from a cheap 25 cent iPod or SB DAC's to the Outlaw was a marked difference.

Next piece I got in were some Insight series amps rated at 220wpc with the double die upgrade. I hooked one up to my 760's and there was a marked improvement. The difference between the Outlaw having to work a little and the sound with AVA being more full and effortless. But, I would attribute the difference to the fact that the AVA is a beast when driving a load, whereas the Outlaw is going to have to work a little. In a well designed circuit, the distortion is going to be really low, perhaps inaudible, but you are going to notice if the opera singer gets on stage and kind of whimpers out the song or really belts it out with gusto and making each note the best it could be. In short, I'd rather have an amp of adequate power (of any brand) rather than looking for "a Bryston" because I like their sound, the ability to drive each note to its potential is much more prominent than comparing amps based on colorations at .000003% THD.

I got the Insight DAC and preamp next.  Adding the DAC was good improvement, and overall more liquid sounding. But you would expect that since I paid $100 more for the DAC than I did the whole Outlaw receiver. The biggest improvement I noticed was hooking up the Insight preamp. While I was quite satisfied with each step of upgrade, I was pretty bowled over by a quality preamp, I thought it would have the least effect and would have been the first thing I cut out if I needed to spend less.

And lastly, Jim sent me 2 pallets of his speakers. Didn't matter what you hooked up, or in what order, or how isolated you made it, easily the biggest upgrade of the entire system. SongTowers or HT2-TL, doesn't matter. I tried to "even" out the systems. Hook up the old electronics to my SongTowers while running the Rockets off all Franks stuff. Still didn't matter, SongTowers sound better to this day with the iPod out, no matter what you do to a Rocket. Frank's DAC and the SB aren't going to magically erase the fact that the crossover in the 760's muddy the midrange compared to the Salk offerings. It won't erase the boom of bottom end that is present even on not so bassy material. Going from .00005%THD on the Outlaw to .000003THD on the AVA is insignificant.

So where would I rate them?

1. Speakers
2. Preamp
3. Amp
4. DAC
5. Source

Note that at #3, I'm advocating you select an appropriate level of power from the maker of your choice. After that, its unimportant, unless you are going for tubes vs SS. Note that I'm not saying that amps don't make a difference or sources don't make a difference. They do, but the difference they make is minimal compared to the output device. It doesn't get anymore barebones than hooking up a 1/8 minijack from an iPod to a cheapo receiver, and even that level of source abuse didn't bring a SongTower down to Rocket level. And $5k worth of solid AVA gear couldn't get rid of all the design faults in the Rocket 760. It made the Rocket 760's sound as good as they were going to get, but it wasn't breaking any ceiling or offering a comparable sound to a higher end speaker. If my wife absolutely put her foot down the call would be easy, keep the cheap electronics and spend the $1800 on SongTowers, rather than try and make the 760's sound better with 5K worth of gear.

[floresjc]

I'm not a measurements guy by a long shot. Never measured a speaker or component in my life, and don't own the equipment to do so.

What gets me about botique upgrades, which are generally quite pricey, is the level of reality you have to separate yourself from to see the benefit.

We live in the real world. Most audiophiles are lucky to have a dedicated circuit for their gear let alone have linear power supplies on everything in the home or convincing their wife not to turn on the hair dryer in the evening or whatever "ideal" or "best" would be. Its kind of like the difference between engineering and science. Science will come to the fight with plans of the best weapons ever conceived, and engineers will just beat the scientists over the head with a club. Sound engineering takes into account the environment and manner in which the item will be used, and I generally see "if you do x,y,z, a,b,c and oh yah, have your own power plant then this device will make 10e-8 inaccuracy 10e-9 inaccuracy, for only $1999!"

While I have seen the value of botique upgrades in the analog world, in the digital world it makes much less sense. At least as a value proposition because even the most cheapo digital output is light years more accurate than a turntable or any of its analog brethren. The DAC is the new dog in the fight. For example, spending 500 or 1000 to upgrade the analog section and power supply of your SB make sense, and most people here seem to agree that if analog is your schtick, then the upgrade is worth it. When people start talking picoseconds worth of jitter or bit errors reading from the disc, you are really into the minutae of the audio sound by the time it hits your ears. Perhaps there is some gain to be had there, but I bet you could easily find another place to spend that grand or two in your chain. For example, the crummy room you are in from an acoustical standpoint.

[Nuance]

Well said, floresjc.  Thanks for sharing that.

[ctviggen]

I definitely believe that room treatments should be way up on the list, assuming one can fit them into the room and the decor.  Personally, I like measurements, as they can tell you things that ears cannot.  For instance, you have boomy bass.  Exactly what frequencies cause the boom and is it possible to notch filter this?  Your ears can tell you there's a boom, but not much else.