[bummrush]

some nice posts going on with this product,,,I wouldnt mind if you could go deeper on this paragraph from above,,thanks
Conversely we have products being offered by the (in my opinion) "not so gifted" set.  They see the struggle to achieve the above goal to be so great and fraught with hazards that they simply choose to avoid the issue altogether.  Instead, they intentionally use either very little or no external feedback and thereby purposefully "wreck" the potential for low output impedance/high DF in their designs.  "If you can't do it right, then don't do it at all" seems to be their motto and "less is more" their mantra.  The upshot is that while it's true such designs do not incur the "secondary" form of distortion mentioned above, then again they do nothing to reduce the "primary" form either.

[Aether Audio]

bummrush,

OK? I'll take the bait.  In order not to offend though I should really re-state my meaning in a different way.  It is a fact of amplifier engineering that the use and intentional application of negative feedback can greatly increase the complexity of the design.  What one might call a "first order approximation" in a basic implementation thereof can be relatively simple in concept, but as they say, "the devil is always in the details" - those details being the actual amount used and its intended use.

A basic application can be viewed as the use of what is called a "nested" or Local Loop.  This is where the feedback is applied only around a given set of components that make up a single stage of the amplifier, as in the Output Stage.  The next level is what is often referred to as a Global Loop.  This is when the feedback is taken from the Output Stage and fed-back to some point very near the input of the amplifier.  When a Global Loop is used, the stage near (or at) the input is often called the Error Amp Stage.  It is at this stage of circuitry wherein the signal from the Output stage is compared to that of the signal originally applied to the input of the amp (say from your preamp).  The original input signal is then often referred to as the Demand Signal.

At the Error Amp Stage the feedback from the output is then compared to the Demand Signal, and assuming a "perfect" comparison, any difference between the two signals (i.e., distortion) creates a new signal, such that it is 180 degrees reversed (out of phase) with the distortion present at the Output stage.  The 180-degree phase-shift (i.e., Negative Feedback) then essentially cancels the original distortion, and now the amp is (theoretically) putting out a perfect and distortion-free signal.

As complicated as that sounds, it gets even more complicated.  The Global Loop can actually be composed of numerous signals summed together from (possibly all of the) different stages in the amplifier, not just the Output stage.  On top of that, the Global Loop can be split to also have included (and it usually does) a signal that is literally tapped directly off of the Output binding posts (where you hook your speaker wire up). 

In this case, part of this "split-signal" feedback comes from before a little passive circuit called a Zobel Network, and the other part comes from after the Zobel Network (the part directly from the binding posts).  The feedback coming from before the Zobel is called the Internal Loop and the part coming after the Zobel is called the External Loop.  The Internal Loop is mostly concerned with amplifier stability at high and ultrasonic frequencies, and the External Loop is mostly concerned with correcting for errors being generated by the Load (loudspeaker) at low (possibly even DC) to mid audio frequencies.

To really grasp all of this one needs to have a good understanding of Control Theory.  Needless to say, it can become incredibly complex, as there are all sorts of things that can happen to mess up any balance of these terms that the engineer does manage to achieve. 

To give you a further idea as to the complexity, the speed (Slew Rate), damping (Settling Time), bandwidth (Frequency Response), noise and thermal profile, along with the basic stuff like voltage and current limitations...of every device in the chain must be taken into consideration.  On top of that, how each device behaves when it goes into Saturation (overload) must be considered too. 

Combining all of that with the possibility of having any combination of "nested" or Local Loops, Internal Global and External Global Loops, and we have one scary set of variables.  Basically, we ARE pretty much talking rocket science here folks.

Now do you have an idea of what I mean by "gifted"?  I once worked under one of the greatest amplifier geniuses in the world, Gerald Stanley, of Crown International.  We were designing and building 40,000-Watt amplifiers for the Medical Imaging industry with a level of complexity and sales volume that made audio applications look like a hobby for tinkerers.  Let me tell you, I'll bet if you ever get an MRI you'll probably sure be hoping the machine doesn't break and that it produces the most accurate results possible.  We're talking the need for a level of accuracy and reliability that you'll never see in the audio market.

So let's try and guess how many Gerald Stanley's there are out there?  Whaddaya wanna bet?  Oh, and he was recently granted a Fellowship in the Audio Engineering Society.  His Master's Thesis project (when he was little more than a kid) became the legendary Crown DC 300 and was inducted into the AES Technology Hall of Fame a while back too.

http://www.crownaudio.com/gen_htm/press/pr158.htm

http://www.crownaudio.com/gen_htm/press/pr157.htm

Along with Gerald, the former co-founder of Infinity John Ulrich, (now of Spectron) http://www.audioprophile.com/eng/agenturer_spectron.htm

and Tranh Nguyen of NuForce http://www.6moons.com/audioreviews/nuforce/ref8.html

come to mind as well.

THOSE are the kind of designs I'm referring to when I speak of engineers being "gifted."  Anything less is just a hack, but then again, I guess I've been severely spoiled.  OK all the rest of you "hack" engineers; I guess you're off the hook. 

-Bob

[br85]

Alright, it's all a bit complex for me to fully grasp, but essentially you have given me all the information I need to understand what these black boxes do. Since I am already a big believer in GNF, I am convinced that your product would be of a HUGE benefit, especially to those of us not willing to shell out more for our amplifiers than our speakers.

I sincerely hope these things take off on the market. Are you implying, by any chance, that BB's will have their greatest effect on amps without GNF circuits? Or that the greatest effect will be on low output Z amps (mostly tube amps), GNF or not?

Reminds me, am acoustic engineer/physicist/audio guru/nutcase once told me about some rare speakers that actually contained an extra set of binding posts for negative feedback (actually couldn't remember whether it was the speaker binding posts or the drivers themselves). Would this provide any more or less benefit than a BB in your opinion? (I'm pretty sure you can't buy any of these speakers anymore so it's not like we're all going to take that route over a BB in any case).

[Aether Audio]

br85,

Are you implying, by any chance, that BB's will have their greatest effect on amps without GNF circuits? Or that the greatest effect will be on low output Z amps (mostly tube amps), GNF or not?

Well... that requires sort of a complex answer, but Ill do my best to make it simple to understand.  First of all, amplifier output impedance is basically the function of two issues.  The dominant factor is the "channel" impedance of the output stage. 

As an example, in order for an amp to be able to output higher levels of current so that it can more easily drive lower impedance speakers, many manufacturers will use 2 or more output devices (transistors or tubes) in a "parallel-wired" arrangement.  That means the final output current being delivered to the speaker is (hopefully) shared equally between each of the individual devices.  By doing this the "on" or channel resistance of an individual device is divided by the number of devices being used.  As the number of devices being used increases, the total output stage resistance (impedance) decreases.  The reason the term "impedance" is used is because the values of this resistance can (and virtually always does) vary with frequency as a function of design.  Of course the amplifier's power supply must also be able to provide the current being called for at any given moment as well, but this is another subject.

The above is the basic reason most larger high-power amplifiers also have a lower rated Output Impedance.  This fact applies whether or not any Local or Global Feedback is applied or not.  Now, regardless of how many output devices are being used, once Negative Feedback is applied it has the effect of forcing the output stage to "turn on" more (harder) in order to squelch (attenuate) any signal that is not supposed to be present (distortion) at the output.  This then has the effect of lowering the "Effective" Output Impedance of the amp.  We must remember that ANY alteration of the output signal from that being being commanded for by the over-all gain structure of the amplifier... is considered a form of distortion.  This means that a simple voltage dividing process which is always present is considered distortion too.

VL = ZL* IL and IL = IT wherein IT = VT/(ZA + ZL).

VL = Voltage across Load (speaker)
IL = Current through Load (speaker)
VT = Total Output Voltage from Amplifier
IT = Total Output Current from Amplifier
ZA = Amplifier Output Impedance
ZL = Load (speaker) Impedance

As we can see from the above simple equations, as the amplifier's Output Impedance increases, the voltage developed across the loudspeaker decreases.  Conversely, if the amp's Output Impedance remains fixed, as the Speaker Impedance decreases the voltage across it also decreases. 

Well, if the amplifier uses no Negative Feedback (be it either Local around the Output Stage or Global) it can do nothing to correct for the voltage drop occurring across the loudspeaker resulting from the voltage that drops across its own internal (Output) impedance.

That means the voltage across the loudspeaker will "sag" to some value less than that which would otherwise be programmed by the amplifier's internal gain.  Such an amplifier's ultimate performance then is extremely vulnerable to the effects of the loudspeaker load impedance.  Seeing that speaker impedance is truly a complex vector sum of pure resistance, reactive capacitance and reactive inductance, (we're talking imaginary numbers math here, +j, -j, etc.) any amplifier using no significant feedback in any form will suffer from a widely varying frequency response at the speaker output, depending on the variations of the loudspeaker's impedance.  Oh, and loudspeaker impedance can (and usually does) vary to significant extremes.

Alright-y then.  Conversely... the application of Negative Feedback to the design will cause the amplifier to "see" any un-programmed voltage drop at its output terminals as an error (form of distortion) and then adjust its output signal to correct for the error.  This is good.  The upshot is that the amp's Effective Output Impedance will decrease as the Load Impedance decreases and increase as the Load Impedance increases.  Doing so thereby corrects for the variations in Load Impedance and results in a flat (hopefully) frequency response at the amplifier's output terminals. 

OK, so now somebody tell me why you still want to use an amplifier that doesn't use any negative feedback?  You say you have speakers that have perfectly flat impedance?  Well, OK then... but if not... don't waste your breath.

Now, we must realize that this process is happening on a microsecond-by-microsecond basis and is actually far more complex than I've just described, but I think you get the idea.  The key point is to remember that while Negative Feedback generally does far more good than bad, its usually not a perfect process and is highly dependant on the over-all design.  When using feedback, the area of worst offense is usually at high frequencies.  If you can imagine both complex musical signals being generated... clear up to 20,000 potential variations per second... AND a complex louspeaker impedance - both coming into play at the same time, it's not hard to imagine how the circuitry could make an occasional "mistake" trying to correct for it all. 

Back in the early days of amplifier design many engineers applied massive amounts of GNF without consideration of numerous important variables, believing it to be a sort of cure-all, particularly in Solid-State designs.  That led to the idea that there was something intrinsically "wrong" with the "sound" of SS and drove many audiophiles back to tubes.  It is a shame that stigma is still at work to a great degree these days, and in many cases falsely so as SS design has progressed light-years from what it once was.

But... in most cases amplifiers aren't perfect yet and feedback loops can still generate small errors that were not part of the recorded material.  This is true whether the amplifier is of a Linear SS, Tube or Switching design, as the majority all use some form of NF for the reasons clearly seen above.  The upshot is that in most cases then, the Black Boxes offer the potential for some significant improvement in system performance.  Again, even in those few cases where the amplifier uses no Global Loop but the Output Impedance above 1KHz is around 2-Ohms or so (less is better), they still offer a potential for improvement in performance - GNF or not.

Now... go measure your amp's Output Impedance from 1KHz on up and you'll have a "sure-fire" set of facts to go by to know whether or not to give the BBs a try! 

Take care,
-Bob

[bummrush]

thanks for writing,while i like great sound ,have a stereo thats probably not to far into the high end arena by some standards,but pretty high end for me,i really appreciate the time spent when i probably am asking basic questions,that the people on this forum  take the time to answer them,i know good sound, but technically the more i can learn makes it that much better.

[dart6]

Hi Bob
I've sent you an email cheers

[Aether Audio]

Brett,

Haven't gotten your e-mail.    Did you send it to aetheraudio@gmail.com ?  If so, I didn't get it... you may want to try again.  In the mean time, just so you and everybody else knows, the old "engineering@4sptech" address is dead and gone.

Take care,
-Bob

[ted_b]

In all my years with audio as a hobby and a business, I have never heard at tweak like this.

I'm playing on a notebook based system with a modified Orpheus One DAC, eAR 1001 mono poweramps and at the moment SP Timepiece Mini speakers. These speakers are the most revealing, accurate speakers / monitors I have ever listened to, they just shows what is in front of them. I my opinion my system was very open, dynamic and life like.

Then Bob offered me an opportunity to try his Black Boxes, one of the earlier Prototypes without the "Smith Cell". On my system it was very obvious, that this was insane. What an improvement... the sound was so lifelike and clear. My wife, whom has become a good listener over the years, was reading a magazine in a chair with here back to the system. She turned around after a few seconds and looked at me and said loudly; " Call Bob and tell Him He's crazy!"

Seriously, this is absolute the most convincing tweak I've ever heard. The sound gets even more accurate with these BB's on. It's like the signal gets cleaned up, or gets rid of some sort of artifacts. Leaving the original signal undisturbed and uncolored. The imagining gets pinpoint accurate and realistic, with a very wide and deep soundstage. Its like overtones and roomcues gets to your ears without any smear or ringing. Just leaving what was originally recorded. It affects all of the signal, the Bass gets cleaner and more articulated, the mids and highs gets more focused. It's like the amplifiers gets more control over the entire range, better start / stop abilities. Voices and instruments are like carved in stone. More realistic than ever.

Imagine a poor TV reception on a cheap antenna, when You turn the antenna, the picture gets cleaner and more detailed. The BB's do something like this to the sound.

I will keep these prototypes till I can get my hands on some of the new ones with the Smith Cell included, period. 

Brian,
Hi.  it was great meeting you at RMAF.  i hope to see you there again. 

(Note: this Danish audio lover has some of the best ears I've ever witnessed; he heard stuff at RMAF, then we checked and sure enough, we were getting leakage through an input, etc.).  Net/net, I believe his ears.  I also believe in Bob and his design expertise; I've put my money in it!!     So, it is with this that i offered to try the 'black box" network pieces parts (without the Smith Cell) since Bob was busty building boxes for others.  he knew the values of the parts very well, of course; he built my speakers.  I installed them yesterday on both hi and low speaker post (one set each).

WOW!  I echo Brian's great descriptions 110%.  It's as if leading edges have been polished clean, and harmonics have been uncovered like geologic finds!  Very nice job Dr Madscientist Bob!   

[mcullinan]

This space left intentionally blank.

[pardales]

Guys,

My previous posting regarding the Black Boxes and amplifier output impedance got me to thinking.  Tics me off that this didn't come to me sooner.   It IS possible that by moving the BBs directly to the output of the amp and then running your speaker cables from it's output to the speakers *may* improve their performance.  I would suspect that would be most notably so with regards to the higher output impedance amp scenario outlined in my last posting (juanito... this means you too).  I sure wish I had thought of this earlier when a few of the first guys had tried them.  They along with the rest of us may have benefited from their experiences.      

Also, they just may work better hooked up that way with those amps that do have a lower output Z as well.  Those of you that have already purchased them and have the version with the pigtails, you can try reversing them and connecting the spade lugs to the output of the amp and then use (what is labeled as) the inputs to connect your speaker cables to.  Have no fear... no harm will be done.  I can't guarantee anything, but it would make for an interesting experiment.

If anybody tries this, please feel free to post your results.  Have a great weekend guys and...

Take care,
-Bob

Just received my BB's today and hooked them up at the speaker end -- this was much more convenient for me. Any tests on whether they really do work better at the amp end? My pair has a "0" and "3" marks on it. Since I am using a low powered tube amp I set it at  what should be "1". I'll try to get to some critical listening by the weekend.

Best,

[rms]

My Mysterious Black Boxes arrived Tuesday and though the science end of what they do is still a mystery to me, even after reading through Bob's explanation, the effect on the sound reaching my ears is definately not mysterious. I totally agree with what BrianDK and others have said so well. The change is not subtle in my system, it is quite profound, and beautiful. The biggest apparent change for me is in the soundstage which is now even bigger and more 3D and more holographic. And I think that has to do with the distinctness and clarity that I am hearing in every instrument. Each musician is now even more of an individual on the stage in front of me and the speakers, even as big as they are, just disappear. I can hear absolutely every nuance in the music, but in a really good way. I have heard some systems, even monitoring desks in some studios, where the clarity was kind of painful. This is not like that at all. It was said by an earlier poster very well "like looking through a very clean window but now even the glass is removed."

I just finished listening to the Yellowjackets "Dreamland" CD and now I'm listening to Leni Stern's "Ten Songs". The word that comes to mind is exquisite. Really, it is just beautiful. The first recording I listened to with the BB's was Chick Corea's "To The Stars" which is a very demanding listen. But it is recorded and mastered incredibly well and should sound phenomenal even though there is a lot happening. It sounded great on my system before and now it is even considerably more 3D with a space and definition around each instrument that is nothing short of amazing! The other interesting thing is that the sweet spot is a whole lot bigger now, like the sound is improved no matter where I am in the room.

[pardales]

First off, thanks to Bob for sending the BB's on tour and including me. I wish more manufacturers would do tours of their gear.

I spent a week with a pair of BB's on tour. They arrived well packed and while they were in decent shape, they appear to have been handled some. You can see my system below my signature line. I hooked them up using the supplied cables right near my Horns and set the dial to the "1" position, which is what is recommended for low powered tube amps.

The BB's did alter the sound of my system but not at all in dramatic ways. Actually, the changes were very subtle and seemed almost recording dependent. On some tracks the bass may have been a little thinner but the midrange more pronounced. On other tracks the bass tightened up a bit and maybe the treble region sparkled a bit more.

I am sorry to say the effects just were not consistent enough for me to reliably judge as qualitatively better or worse. In fact, at times it was very difficult for me to get a handle on what the BB's were doing. Chalk it up to system dependency I guess.

Best,

[dart6]

Hi Bob
 Did you get my email yesterday cheers

[mixsit]

I just figured I'd give a hey there' 'cause its been a while and ask how things are going too.
Really hoping to see your speakers coming back out the other side of all of this.
I've been putting off swapping out' the SP flag links in all my forum sigs. 
Best wishes
Wayne Smith

[bbchem]

  Hi, its me again the Mysterious black showed mysteriously today!!

I opend them up and began to play around. Played 4 songs without, then repeated at 0,1 , 2, 3
I use Mapleshade Cds as a reference fo me. I think their sound is the most realistic to me.
I am using a Rogue 90 tube amp and a tube preamp. My speakers are timepiece 3.0s.
The sound of these is world class as it is, as some of you already know. Well at #2 the sound is coming out of the box pumped like a 3d picture expanded on a large screen! The instrument air is blown up,  the bass is tight and rock solid!!  I can't conceive of anything sounding like this although I had said that about the 3.0s in the past. I have used several tweeks and this takes the cake in my system. The absolute BOMB!! 

[bbchem]

Hi, its me again the Mysterious black showed mysteriously today!!

I opend them up and began to play around. Played 4 songs without, then repeated at 0,1 , 2, 3
I use Mapleshade Cds as a reference fo me. I think their sound is the most realistic to me.
I am using a Rogue 90 tube amp and a tube preamp. My speakers are timepiece 3.0s.
The sound of these is world class as it is, as some of you already know. Well at #2 the sound is coming out of the box pumped like a 3d picture expanded on a large screen! The instrument air is blown up,  the bass is tight and rock solid!!  I can't conceive of anything sounding like this although I had said that about the 3.0s in the past. I have used several tweeks and this takes the cake in my system. The absolute BOMB!! 

To add, some closing remarks after 9 days of testing.
1. I have timepiece 3.0s killer as you know
2. Read #1 again
3. Let me say this, you know the value of something when you miss it. This is the case with the Black Boxes. When I pulled them out of the system, the sound flattened out. Now consider the amazing timepieces, that is no small achievement since they are masterful in soundstage and dynamics etc.
4. I played Rock, Jazz, Classical, Newage and others, through a Transport/Dac setup.
5. The term " ON STEROIDS" is the best example of what happened. The speakers open up and extend out in all directions with smooth and 3d sound like nobodies business!!
6. There is no grit or artifacts added only lush and full and smooth music beyond that of even the TPs
7. Again you will never want to go back after trying these as happened when I pulled them out
8. Bob Genius again, IMHO Bill

[konut]

After a couple of months of using the BBs on Omega A8s, I switched back to my Timepiece Minis to listen to the new Beatles boxed set.  JUMPIN' JEHOSAPHAT! The precision of the sound stage is staggering! Near as I can tell, and I'm talkin' outta my ass here(some would maintain that I'm always talkin' outta my ass), the BBs impart a precision to the phase of the signal to give that exact rendering of sound stage.

[JakeJ]

Here is my report on Bob's new tweak:

I have recently had the pleasure auditioning the ?Black Boxes? from Bob Smith?s new company Aether Audio.  I found them to be quite interesting and worthy devices for me.

A bit about my system, it is a fairly high resolution system without suffering the hi-fi sound that, to my ears, is usually dry and lean, with perhaps a bit of etch on the top end that leads to listener fatigue.  My system errs to the warm side of neutral but retains the ability to render a highly defined soundstage with all the spatial cues the recording has to offer up.  The current equipment line-up is:

SOTA   Sapphire Turntable
SME M@-9 Tonearm
Lyra Lydian Beta Cartridge
van den Hul Tonearm I/C
Adcom GCD-750 CD Player
Analysis Plus Silver Oval   I/C
McCormack Audio   ALD-1 w/ SMc mods Full function preamp
DIY Neotech NEI-3002 UPC-OCC I/C
Valve Amplification Company PA-160 Mono tube amps
Omega Mikro Planar V Speaker cables
Genesis 5.2   Speakers
Audio Magic   Stealth XXX Power conditioner
Audio Magic   Various Power cords

Overall the system is balanced and uncolored.  Just need a bit of speaker placement tweaking and some more room treatments.

The first thing I noticed after inserting the BBs in my system was an increase in height, width, and depth in the whole soundstage.  The second thing I noticed was they didn?t change the system?s voicing or color the sound in any way, no small feat as I have heard some tweaks that really change the sonic cloth of a system.

Next, and to a lesser degree, I noticed a refinement to the instrument placement and layering is improved.  With classical recordings sometimes the orchestra gets compressed in size in relation to real thing but the BBs seemed to restore some if not most of that feeling.

On still a lower level of effect was there slightly more air around the instruments and ambient info was clearer giving a better sense of the recording space. Along with this or perhaps as a function of it, bass was better defined and tighter.

The next day I removed the BBs and listened for about half an hour before I wanted them back in.  The first and most obvious item was the moderate collapse of the soundstage.  It doesn?t completely shrink to nothing; it just loses what I perceive as about two feet in height and width and about three feet in depth (which I missed the most).  The refined instrument placement does almost disappear but that may also be due to soundstage shrinkage.  Kind of like going swimming in cold water for an extended period of time, if you know what I mean.

On my JVC XRCD Sarah Vaughn?s How Long Has This Been Goin? On? Track ten, ?When My Lover?s Gone? is a duet with just Sarah singing and Louie Bellson playing the drum kit.  Always before the individual drums sounded like they are as wide as the space between the speakers regardless of which drum was being struck.  With the BBs in the snare was now coming from a spot just inside the left speaker and the big tom now came from a location just inside the right speaker with cymbals and other drums filling the space in between correctly.  I like these little doodads and see a set of these adorning my system in the near future. 

Jake Jacobson

[DeadFan]

Hi all Aether Audio ( SP - Bob Smith ) fans.

Just thought I'd pass on my good news. I'm partway to being SP - Revelation owner. I have made a downpayment on a pair being made for Paul.
Unfortunately Paul (like many others in todays financial climate), has fallen on hard times and needed to onsell before he could take delivery. The Rev's are in Walnut hardwood and fron the photo's Bob supplied, look gorgeous. From all reports they sound even better than they look!!!!

I'd like to thank all you AC/SP Tech, forum contributers, as your enthusiasm coupled with my assessment of Bob (via his many informative posts) helped make an expensive (for me) purchase, sight unseen.

I am hoping I can obtain some more direct advice in regards to the rest of what I hope will be my "final system".

I will be leaving my amp upgrade for a little while as I already have a pair of NuForce Ref 9V2SE and they should be able to drive the Revs reasonably.
When I have looked after my more immediate need (source equipment) I will research amps more thoroughly.

With source equipment I had thought I would purchase both a high grade Redbook CD player and a computer based setup like the Modwright/Transporter. I know people like Ted_b and DoubleUgly have experience with Modwright. Any suggestions as to best cicle/thread to pose that type of question?

Regards

Graham

[Aether Audio]

Guys,

Thanks for your posts and comments on the BBs.

I just wanted everyone to know that we'll be posting our new website any day now.  The URL will be www.aetheraudio.com

I've e-mailed just about everybody I can think of that are former SP Tech customers, but some may not come through for whatever reason and some I may have missed.  In that, we're looking for SP Tech owners that would be interested in becoming reps for Aether Audio now.  In the end we may have a dealer or two, but our primary focus will be on having our owners offer potential customers an audition from out of their home.  We believe an actual owner is a far more credible rep than any profit-driven dealer.

If I've missed anybody and you see this and are interested, please contact me at aetheraudio@gmail.com.  I'll then give you further details as to how it will all work.  We already have a few guys signed up but would like to see more.

Anyway... we're soon to be "back on line" and just as a little teaser, the new site BLOWS AWAY any of former SP Tech's websites.  There's enough content ther to keep you reading for hours.

Finally, we're also asking all speaker owners that are willing to send us nice pics of their rig for posting on our gallery page.  We have a few now, but sure would like to have as many as possible.  Just send them to me at the e-mail address above.

Thanks again for you ongoing interest and support, and rest assured were here for ya whenever your in need of new goodies. aa

Take care,
-Bob