Lifeforce

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Seano

Re: Lifeforce
« Reply #20 on: 3 Jul 2006, 10:45 pm »
Yes, a 100W Lifeforce is already designed, laid out, and 14 production boards are sitting in my workshop ready for stuffing.  I've built a couple already, though not yet mounted them in a box for auditioning.  This model will arrive when the 55W is properly launched and the initial sales spurt abates!

Typical! i ALWAYS PICK THE MODEL THAT'S LAST IN LINE FOR (ah yes caps lock) now where was I.........yep that's right I always end up last just waiting waiting waiting for something everyone else has already got......left out again no-one to play with always forgotten.......actually given my 100N+ is still sitting in a cupboard waiting for time and renovations to make way for fiddling with stereos.......I can probably afford to be a little patient :oops:

Hey Hugh........have you tried the Lifeforce out on those with uncritical (or just plain average like mine) ears yet?  I'm of the view that people with sensitive 'trained' ears often seem to tend towards overstating what they can hear whereas uncritical ears often go off first impressions - basically if it is an obvious thing then even they can tell.  Basically I'm curious if what you have is a ten tenths shift or a physical jump......... :scratch:

AKSA

Re: Lifeforce
« Reply #21 on: 4 Jul 2006, 12:27 am »
Hi Seano,

Lots of guys have the 100W - you ain't Robinson Crusoe!!

Ten tenths or physical jump.  Hmmm.  A good friend's wife, who is not an audiophile and reckons we are all overstating our observations, told me she really missed the new amp when I took it away to be replaced by the original 55N+.  She was 'caught' humming and tapping her foot at a late night engagement by my friend recently.  He looked on agog!  She just said she really liked the sound.

The difference is immediately obvious, even to my wife and daughters.  They don't identify it as such, but the younger, Alessandra, complains when the N+ plays because she thinks it's not as clear.  If you never heard the LF, however, you would not know this.  I have to be honest, we simply don't miss what we don't experience.

It's a bit like excellence in any field.  If you've never driven the V12 Seven series BMW, you'd not know just how good an automobile can feel, and your old GM Commodore would be quite satisfying.  I now drive an old Toyota Cressida, but for all it's antiquity, I could not drive a modern GM or Ford car any more.  It wouldn't give me any satisfaction.  The LF is a bit like that.

Not much of an answer, but rather than getting crossed up in self flagellating hype, it's just a class thang.  Bear in mind you are talking to an obsessive, who enjoys the chase for no other reason than it can be done.  This is not pragmatic need, this is obsessive aspiration, but for many of us (and I suspect you, too!), there is always at least one area of our lives where this drive is consuming.    :dance:

Cheers,

Hugh

SuperMart

Re: Lifeforce
« Reply #22 on: 4 Jul 2006, 02:37 am »
Hi guys,

I had to chime in here being the older half of the "good friend's wife" in question! You make a very good point Seano and one that I'm taking on board in my extensive listening sessions with the Lifeforce. Before I had the current Lifeforce production model in my system I also extensively listened to the beta version which was substantially similar to the final incarnation although not quite as refined as the final version - the beta was not sporting those lovely Black Gates. As part of my listening tests I returned the beta Lifeforce to Hugh and reinserted my 55N+ back into the system. I find this process to be very helpful in making comparisons and helps to temper those inevitable feelings of "gee whiz this new thing's different/great/louder/whatever." A bit like test driving a new car - once you drive back home in yours you have this feeling of "this thing's not so bad after all." So I'm trying very hard to take account of this in my listening to the Lifeforce. I'm also feeding it with discs that I feel are challenging - discs that I would normally avoid playing because I have found them to be harsh/complex/lots of high end fizz and so on. I'm also playing some pretty ordinary piano recordings and a lot of very busy jazz albums.

Without starting the review in detail I have to say that the Lifeforce is quite obviously, on first listen cold and out of the box, a startlingly refined design with astonishing capabilities. There you go I've been trying to avoid this sort of colourful description but I think ACers should be aware that the Lifeforce is not just another refinement of the 55 it has clearly leap-froged it into another class above.

Again, before getting back into the listening chair, I make my usual disclaimers about my friendship with Hugh - he's a hard bloke not to like - and my previous purchases of Aksa products.

Cheers,   

LM

  • Jr. Member
  • Posts: 250
  • Lyn
Re: Lifeforce
« Reply #23 on: 4 Jul 2006, 06:01 am »
Seano,

I do hear where you are coming from but be thankful that at least the stereo fraternity have it pretty easy compared to the surround sound world.  Here there are Blu Ray v HD format wars around the corner, newer HDMI standards to be settled and chipsets made and ideas of more than 7 channels etc. etc.  Unless the new technologies fail to fully catch on such as with SACD and DVD-A, chances are that any investment in receivers, pre-pros, DVD players etc bought today will have quite a short life for those that want to stay at the leading edge.  My 7 month old HT receiver is already outdated.

On the other hand, I don’t see how anyone with an existing AKSA particularly Nirvana models can feel other than pleased with what they have.  At least they will still have the second best amp in the world  :D and I for one would be mortified if Hugh decided to rest on his laurels.  I will be happy to keep playing my vinyl and CD collection till the cows come home and a good stereo amp and speakers will give huge pleasure for ages to come, even when better amps emerge, as they must.  Vandersteen speakers have been made to essentially the same design for 20 years and I don’t hear too many calling them outdated.  I for one am certainly far more comfortable with the rate of refinement in the stereo world as opposed to the massive rate of change in HT.

simbloke

Re: Lifeforce
« Reply #24 on: 4 Jul 2006, 09:24 am »
Hello,

I'm very pleased to here about the new Lifeforce  :D. The upgrade offer is particularly nice and not something to be expected in today's world. It's nice that finding/buying/building and finally listening to an Aska is more than just a commercial transaction. It may also help me get the wife to agree (though I have no idea of the cost yet!).

There is one catch though. What on earth would I listen to whilst waiting for the postman???

Regards,
Simeon

Geoff-AU

  • Jr. Member
  • Posts: 122
Re: Lifeforce
« Reply #25 on: 4 Jul 2006, 01:13 pm »
Hugh,

This new module certainly seems like the best thing since sliced bread, judging by the thread!

I am still quite content with my AKSA 55 but obviously would always like to improve (speakers will be the next link to change though).

Is there going to be a time limit on the trade-in offer? (I don't mean "trade in this month or you miss out" so much as do you see yourself offering the trade-in for a year or so.. or will it be a permanent offer?)

AKSA

Re: Lifeforce
« Reply #26 on: 4 Jul 2006, 01:51 pm »
Hi Geoff,

It won't be permanent, but it will last a long time.  You need not be concerned on that score!!

I don't expect people to rush out and change over until they have more substantive proof of the quality of the sonics, so this could take some time.  I'm working on product descriptions, reviews, and forum visibility to push it into the radar, but this is tricky to sustain!

Furthermore it will take some a little time to decide as potential buyers save their pennies.  I will price it for the N+ owners so that it's just a bit cheaper than the original AKSA 55N+ kit.  This ain't cheap, but it's really that good......

Cheers,

Hugh

Johnny

Re: Lifeforce
« Reply #27 on: 4 Jul 2006, 04:14 pm »
Hugh,
Will the stock 55 power supply do the the LF justice? (I'm not sure if N+ upgrades effect the ps.)
I have the original (optional at the time) ps kit  with 47k x 50 v Nichicon caps, BYQ28E-200 diodes and use a stereo pair of Avel Linburg Y236504.

Clink!
Thant's the sound of my piggy bank :green:

Cheers!
John

Jens

  • Full Member
  • Posts: 345
Re: Lifeforce
« Reply #28 on: 4 Jul 2006, 07:31 pm »
Hugh,
Will the stock 55 power supply do the the LF justice? (I'm not sure if N+ upgrades effect the ps.)
I have the original (optional at the time) ps kit  with 47k x 50 v Nichicon caps, BYQ28E-200 diodes and use a stereo pair of Avel Linburg Y236504.

Clink!
Thant's the sound of my piggy bank :green:

Cheers!
John


Hi Johnny,

When I upgraded to the N+ (which includes better caps for the PSU - Nichichon Gold Tunes), I started out with just changing the caps and played a while before modding the PCBs.

No doubt in my mind that "just" changing the caps was a clear improvement. Power supply caps do play a fairly important role, it seems.

I absolutely plan to go to the Lifeforce, using my existing N+ PSU, but I might even be tempted to try BGs instead of the Gold Tunes  :wink:

jules

Re: Lifeforce
« Reply #29 on: 4 Jul 2006, 11:21 pm »
Hugh,

a few of questions that might be of interest to others ....

   * Will the lifeforce be pop free when it's switched on/off? I'm using a ribbon tweeter and the N+ was of course very kind in this regard.

   * With the board exchange scheme, would you accept stripped down boards? Right at the moment I can't think what I'd do with the parts but a few spare black gates sounds useful.

   * Is the 100W form a relatively straightforward development from the 55W base or do you anticipate a fair amount of coffee and cafe time to do the processing?

I'm sort of presuming that this is the end of the line for the kit 55W and that once the 100W Lifeforce is alive it will be the end of an era for AKSA in the way many of us have come to know it. I hope you'll figure out a way to keep this seminal element of AKSA alive but at the same time the completed retail units will be a wonderful buy for that large part of the market that wants something off the shelf.

jules


ginger

Gingers Lifeforce Analysis
« Reply #30 on: 4 Jul 2006, 11:50 pm »
I was going to post this the other day BUT decided to pass it by Hugh first to make sure I wasn't giving away any of his intellectual property. Now with Hugh's permission:-

Those of you who have "hung out" here for a while will know that I "earn a crust" as an electronic design engineer. Unlike a couple of posters here I have NOT heard the Lifeforce (yet) however Hugh did send me the schematic (commercial-in-confidence) for me to do an analysis and to comment on his design.

Based purely on that analysis it is quite easy to see why the Lifeforce would offer superior performance. There are two major schools in amp design.The lazy way is to have massive amount of open loop gain and then throw an equally massive amount of feedback around it. This is the way to design one of those 0.001% THD "Cold Sterile and Boring" Amps which "infest" the commercial offerings down at the local HiFi Shop. The proper way is ensure that the Open Loop response is "pristine", has just enough gain, and throw just enough feedback around it as required. This has always been Hugh's design philosophy and the Lifeforce takes this philosophy to new heights.

Since we are concentrating on Open Loop performance - what is the Open Loop Gain (OLG)?

For 95% of SS Amps (including the AKSA range) we can write:

OLG = gm(diff amp) x beta(VAS) x  ZLoad(VAS) x output stage gain.

Where:
gm(diff amp) = diff amp output current vs differential input voltage (Vin - Vfeedback)
beta(VAS) is the current gain of the VAS (Voltage Amplifier Stage)
ZLoad(VAS) is the load impedance of the VAS
NOTE: VAS Output Current develops the Output Voltage across ZLoad(VAS)
Output Stage Gain = approx 0.96 (its just a power buffer)

From that it is easy to see that to improve open loop response, then we need to concentrate on improving the diff amp and the VAS, where all the gain is (because the output stage gain is approx 1) and indeed the N and N+ mods to the AKSA55 and 100 did largely concentrate on doing just that.

The Lifeforce has taken this philosophy to a new level.

In the Lifeforce the diffamp has had a total redesign to give it the "turbo charger" treatment.
As a result:
- The gm vs differential input voltage characteristic (which looks like a bell curve centred about 0V input) has been significantly flattened which means there is less COMPRESSION of larger input signals - this will give enhanced bass drive and control.

- The linearity of the actual devices has been enhanced which will reduce 3rd (and other odd) harmonic distortion

- The balance of the diffamp has been enhanced which will give reduced 2nd harmonic distortion

- The output impedance has been reduced which enhances its ability to drive the VAS AND in particular enhances its ability to drive the charge and discharge currents of the dominant pole capacitor around the VAS. This will significantly reduce high frequency distortion, improve the high frequency response and increase slewrate (which will also reduce intermodulation distortion).

I would expect all this to give better imaging and air and better detail particularly at higher frequencies.

The VAS Stage has had enhancements to reduce interaction between the dominant pole capacitor and actual device capacitances - I would expect this to emphasize the improvements offered by the "turbo'ed" diff amp.

A few years ago Hugh sent me details of a modification to the AKSA55 to make it sound more like a Valve(tube) amp. You will be please to hear (or you should be) that an enhanced version of this mod. has been integrated into the new design.

The "tricks" which gave the AKSA55 and 100 that "warmth" and "emotion" have been retained.

The Output Stage (the Power Buffer) remains much the same.

So from a pure analysis and without even having heard the Lifeforce I expect it to provide a significant step up in performance - and all achieved without any major increase in open loop gain or feedback - that is, it's been done the "proper" way.

I'll be signing up for the upgrade - how about you?

Cheers,
Ginger (Ian Miller)

AKSA

Re: Lifeforce
« Reply #31 on: 5 Jul 2006, 12:17 am »
Hi Jules,

Congatulations on being made a Facilitator!  John doesn't give this away lightly......   :idea:

You ask very good questions!  Here goes:

Quote
* Will the lifeforce be pop free when it's switched on/off? I'm using a ribbon tweeter and the N+ was of course very kind in this regard.

Yes, it is almost completely silent.  There is considerably less pop than the AKSA, in fact, and no DC voltage applied during switch off to the speaker.

Quote
* With the board exchange scheme, would you accept stripped down boards? Right at the moment I can't think what I'd do with the parts but a few spare black gates sounds useful.

Actually, no.  The trade-in value (which will surprise you when you see it!!) is based on a fully operational, functioning amp.  Reason:  I may offer them reburbished for people wanting a built up AKSA, which I fully intend to keep offering in the kit market.  I'm sorry, Jules!!  But you'll get fresh BGs in the Lifeforce!   :thumb:

Quote
* Is the 100W form a relatively straightforward development from the 55W base or do you anticipate a fair amount of coffee and cafe time to do the processing?

Yes, it is a logical development, and all the work is now completed, including an elegant pcb with identical width to the present 100W board, and depth another 3mm at 79.5mm.  Both pcbs are being made in quantity as we speak.  Ginger (Ian Miller in Adelaide) has just done an exhaustive analysis of the circuit and design philosophy and has just posted his analysis in the post immediately preceding.  Thank you, Ian, I acknowledge your analysis with gratitude, and appreciate the gesture.  Actually, I even have a couple of 100W Lifeforce boards nearing completion, and will use them to fine tune the compensation scheme. 

The Lifeforce is the result of three years of formal, hard slog.  There are five prototypes lying on the cutting room floor, three tube/SS hybrids, and two fully SS.  None measured up sonically, yet all took months to develop, hundreds of hours and embarassing investments of dollars.  The integrated Lifeforce topology was only conceived about two months back;  things move quickly only when the right formula is found.

Nevertheless, many lattes will still be consumed into the future......!!   aa

Quote
I'm sort of presuming that this is the end of the line for the kit 55W and that once the 100W Lifeforce is alive it will be the end of an era for AKSA in the way many of us have come to know it. I hope you'll figure out a way to keep this seminal element of AKSA alive but at the same time the completed retail units will be a wonderful buy for that large part of the market that wants something off the shelf

In some ways this is true, Jules.  However, as Aspen changes direction I'm conscious of the risk factor, the difficulties in negotiation and getting paid, the strategies which may involve marketing professionals, and the insane complications of labour, shipping, packaging and warranty.  At my age, and with health issues inevitably emerging, I don't want to do this much, my roots are in DIY, but I must earn a living wage, and I look to my own Father who started a business 22 years ago at age 62 which is now employing eight people and turning over millions each year.  It can be done, and I must look to the last 13 years of relative indolence doing what I loved most and smelling the roses, so in a sense, I've already enjoyed my retirement and it's time to roll up the sleeves again!!   :whip:

That said, most of my new products will be tested in the DIY market.

I believe we should all try to take the Death Bed View (DBV).  This may seem a little tacky or even macabre, but I try to make life choices now based on how I will feel at the end of my life, looking back.  It's true none of us will look back and say, 'I should have spent more time at the Office', but I think most of us would look back and say, with regret,  'I had a talent, but I never worked it through'.  I seem to like electronics, and find it not too hard to follow;  this came late in life, at 44, and was hard won.  Now it's there, it's worth doing something with it, but I'm no inspired Tesla, so it has to be by sheer repetition, and this involves long hours of experimentation, looking for the needle in the haystack.  When this gets me down, I'd like to write a few short stories in the SF genre, like Grey Rollins, just for relaxation.  In fact, this is the way a lot of practitioners work, and we can do a lot worse than spend our lives looking for the needle!!   :lol:

Cheers,

Hugh

« Last Edit: 5 Jul 2006, 12:28 am by AKSA »

LM

  • Jr. Member
  • Posts: 250
  • Lyn
Re: Lifeforce
« Reply #32 on: 5 Jul 2006, 09:10 am »
I can vouch for the essentially pop free shutdown.  And thanks Ginger and Hugh for two very enlightening posts.  Great stuff!

Felipe

Re: Lifeforce
« Reply #33 on: 5 Jul 2006, 09:23 am »
Just want to leave my support here, to Hugh and to all that are helping him in his quest.
He has been delivering us a full hand of beutifull products for some time now, and i thank him for not leaving us (AKSA owners) out of the deal with this trade-in offer !  :thumb:

I am glad that you keep on improving your products and really hope you start making pennies $$ now !

Put me down for the 100w trade-in as soon as its available. I am NOT passing on this one ! Gotta have it !

Felipe

JohnR

Re: Lifeforce
« Reply #34 on: 5 Jul 2006, 10:09 am »
Seconded.

And thank you Ginger for your analysis :thumb:

rabbitz

Re: Lifeforce
« Reply #35 on: 5 Jul 2006, 01:10 pm »
But you'll get fresh BGs in the Lifeforce!   :thumb:

Noooooooooooo!  :cry:

Grumpy_Git

Re: Lifeforce
« Reply #36 on: 5 Jul 2006, 02:20 pm »
Hugh, how much for a fully assembled Lifeforce?

I'm feeling lazy and my box making skills suck big time.

 I want something pretty.

Nick.

AKSA

Re: Lifeforce
« Reply #37 on: 5 Jul 2006, 10:04 pm »
Hi Nick,

This ain't gonna be cheap, because I have to make it look good and it's a plug and play.....

I don't know in detail yet, Nick, but I'll get back to you.

You might just have forced me to get moving and set things up for the retail product!!  Thank you..... :oops:

Cheers,

Hugh

Grumpy_Git

Re: Lifeforce
« Reply #38 on: 6 Jul 2006, 08:18 am »
All this talk about wanting to make money is just a lie for your wife isnt it!

you have no interest at all making a big pile of cash, to quote Slim Devices, "It's all about the Music"!

Nick.

AKSA

Re: Lifeforce
« Reply #39 on: 6 Jul 2006, 10:17 am »
Nick,

Money is the conventional measure of success in this facile world.  Not making any money brands one as a failure of sorts, but the truth is I don't need a lot of money to survive.  Actually, almost no-one does, if they are modest and resourceful.

But a good wage would be nice........ :lol:

On a more serious note, Lifeforce 55 prices are now posted here:  http://www.aksaonline.com/buying/buying_price.html

Cheers,

Hugh
« Last Edit: 6 Jul 2006, 12:41 pm by AKSA »