[AKSA]

Folks,

A clean slate for Lifeforce listening impressions!!

Please reserve for ACTUAL REVIEWS, people who have HEARD IT, and wish to comment on the sound, good or bad.

Discussions about other aspects, such as value for money, relevance to DIY, etc etc, should be put into a fresh thread.

Sorry for the bother!

Cheers,

Hugh

[aurelius]

As moderator, do you have the capability to merging all of the genuine listening impressions into one thread?  Would be very handy.

[stvnharr]

Due to the unfortunate circumstance with the original thread I thought I would repost my original impressions here at the beginning of this thread.  Continued listened has only reconfirmed everything I originally wrote.
--------------------------------------------------------------------------------
Hello all,
Here are some Lifeforce impressions from one of the first to take the plunge.

LIFEFORCE

I have one of the first pairs of Lifeforce55 modules Hugh made for sale.  I’ve finally had enough time with them to be able to write a bit about them.

First, some background info; I listen mostly to classical sacd’s, high rez recordings.  My speakers are one of a kind 2.5 ways with Seas W18E drivers and Hiquphon OW1 tweeter, high rez drivers to be sure. My speakers are set up 7 feet out into the room, and I sit in a near field position, and have a very good 3D effect from this setup. My N+ amp has attenuators build in, and thus I have no preamp. 

I heard one of Hugh’s Lifeforce prototypes during a visit in March.  It was just a short casual listen, but I was so impressed by the sound that afternoon that I wrote Hugh the following day that I felt he was really on to something with the new design.
Once Hugh published his price for the new Lifeforce modules, well, I didn’t really have to think too long before ordering a pair.

What most got my attention in the casual listen at Hugh’s were the superb clarity and three dimensionality of the music.  This three dimensionality stood out to me, as music I had previously heard at Hugh’s had never really sounded that way.  However, my own system, setup, and listening choices already stood out for high resolution, clarity, and three dimensionality.  I was not sure of how much improvement the Lifeforce would really add, as the music was already quite good and at a fairly high level.

After giving the amps some hours to play and myself to listen, I can say that the Lifeforce raises the level of music playback up a fair bit.  What I believe to be the strength of the Lifeforce is an increase in the low level detail of the music.  This gives the music a higher level of clarity and precision, a much firmer stereo image, and a much more natural sound.

Low-level detail is a real benchmark of an audio system’s quality.  Classical music is all about musical detail, decay, and notes fading to infinity.  The more an audio system is able to resolve these musical notes, details, and decays the more natural the music will sound. The more low level detail present, the lower one needs the volume to be, in order to hear everything that is there in the music.  If you have to turn up the volume in order to “get into the music”, well, it’s just not there. It’s just loud.

I have made numerous changes to my audio system through the years.  And some of the more profound changes have been amplifier changes.  Going to a BAT VK60 several years ago, made the music overall sound so much better than before.  The Aksa N+ kept the VK60 tonality and added superb bass response and driver control, as I described in my testimonial that is still on the website.  And now………………
The Lifeforce has increased the low level detail that is in the recorded music, to a superb level.  And I think it is a performance level on par with, or beyond, the highest performing audio amplifiers.

I think this is why the music sounded so very good at Hugh’s.  The Lifeforce seems to raise the level of performance of the total audio system to a very high level.  I certainly think this is what Aurelius was alluding to in his comments about Hugh’s system with Lifeforce being a notch above his N+ w/Orion’s.

Much has already been written about the increase in bass performance of the Lifeforce over the N+.  Classical music doesn’t exactly have the pulsating bass line of most popular music.  Classical bass is more of a foundation to the sound of the orchestra, best done with a large bass driver or subwoofer.  My system here has neither.  Yet there have been times in certain pieces when I’ve noticed the tympanis sounding much louder than before, and other times where there was a greater firmness to the orchestral foundation.

The other day I put on a couple of old popular music rbcd’s that I still have in my collection. And like WOW, where’d that bass come from!  It was like my nice little 55-watt amp had become a mini Krell. And my 7-inch W18E lower woofer (the .5 woofer) had become a 12-inch bass monster.  This definitely got my attention!
Oh, and I must mention that I wouldn’t really think of this quality as slam.  I don’t really think that slam is a very good musical term; although I realize that others might beg to differ.  I’d rather say that it’s “increased bass performance”.

At this same time, I also put on a couple classical rbcd’s still in the collection.  Again, another WOW, as I heard more resolution and detail than ever before in these discs.  It was somewhat like the resolution had almost risen up to sacd level, although not quite.

In conclusion, the Lifeforce is such a high performer that every other component in the audio system seems to also have it’s level of performance significantly raised as well.
I think the Lifeforce is the most cost effective improvement one can make to one’s audio system, provided of course that you already have an Aksa.

I rather like this Lifeforce amplifier.  It gives the music a Life Force all it’s own.  Or perhaps I should say that it gives the music more LIFE!!!!


Steve
 
 
 

[LM]

As with stvnharr above, just repeating what I wrote some weeks ago in the other thread as nothing further changed over the final week that I had the demonstrator in my house except an ever deepening respect for this amp.  I genuinely miss it at the moment and as good as stereo is on my Arcam HT kit, my real (separate) stereo area is sadly silent.  My only mistake was to listen to it so early and well before a fully built item was available for purchase as Hugh is fully commited to his upgrade programme first up.  I don't currently have time for DIY so unlike many existing AKSA owners, I have been judging the LF100 in competition with Arcam, NAD etc separates that I might otherwise have bought.

......Previosly posted Jul 31..................................... ..........

Some two weeks ago, I posted my first ‘wow’ impression of the LF55 after listening at AKSA HQ for an hour or so through Hugh’s backup speakers.  So I couldn’t wait to get it home and try it in my dedicated stereo system but by the time the opportunity came up this weekend, it was the LF100 that Hugh placed in my boot.

Having reread most of the previous posts about both the LF55 and latterly the LF100, I’ve realised that I have found what everyone else has already said to be true and that repeating the descriptive accolades would simply take up space.  So I will take a slightly different approach and apart from summarising my impressions at the end, I will rather describe what the LF100 (trial) has done for my system.

To set the background then, I have been deeply researching speakers over recent times as my taste is for accuracy and detail, but neutral.  After much listening, Vandersteen 2CE sigs headed my list but in the ‘saving up’ meantime, I had picked up some very old but pristine Vandy 1s.  Whilst they are bottom end of the range, I had found them very good but lacking a little something, dynamics I suspect, with the previous amplification I had heard them with.  Whilst lovely, they were perhaps a touch more laid back than I wanted.

So, enter the LF100 stage left, hook it up to the Vandy’s with a reasonable CD source and lets see how they go together.  Well my first reaction is that ‘wow’ simply doesn’t cut it as a descriptor any more.  This has been simply the most pleasantly, astonishing upgrade weekend that I have ever had.  Talk about coming alive.  The LF100 has been simply brilliant in bringing out the best in the speakers.  Base is now amazing for a 2 way system.  That lower octave I was missing over the bigger 2 series is of course still missing in an absolute sense but the drive and slam on what I do have, is excellent.  More importantly to me, the overall naturalness and musicality across the whole frequency spectrum is pretty much everything I have previously dreamed of.  And I can’t even imagine how much better the next model up might be.

I have thrown every sort of music I can at the system to see if it trips up anywhere, but not so far. I hope I am not going too far now but I prefer the LF100 overall to the Glass Harmony for the reasons above.  To me it is quite neutral and while it perhaps lacks that little bit of extra warmth and finesse in the midrange, it is so punchy and fast such that to my ears it is reproducing all of the musical detail in an extraordinary way.  I have one quality recording of a string quartet that I have listened to about three times now and I still find it hard to grasp just how realistic the timbre of the instruments is.  Imaging and soundstage were superb such that you are really part of the performance.

Things I have particularly noticed were the handling of decay; brilliant.  Echo and reverberation detail are such as I have never heard before and as well, there is a totally natural instrument separation and an almost holographic soundstage.  My overall impression was of effortless rather than absolute power giving great dynamic range, transients, tonal purity and superb openness and imaging.  The dynamics gave me a huge sense of the performance, particularly during dynamic orchestral passages, that was very, very impressive.  There was no congestion, distortion or harshness that I could detect.  Strings, wind and vocals are remarkably lifelike.  String plucks are clean and all the stages of a drumbeat detectable.

I hope everyone reading this realises that I am neither a true audiophile nor a professional reviewer, just an enthusiast.  I haven’t listed any negative points as I have not noticed any.  I am sure, on rereading the above, that my description may sound a little enthusiastic for essentially budget speakers and source, but that’s how much the LF100 has enhanced my system to my ears.  In the end, I virtually dragged Hugh around to my place to have a quick listen to the amazing synergy between amp and speakers in a customer system.  I hope it was worthwhile Hugh.  My only problem now is being able to hang on after returning the demonstrator amp till Hugh can supply my order.

[DSK]

Below is my post from 18-Jul-06 that opened the original 'LifeForce Listening Impressions' thread, followed by some more recent thoughts...

Though there is already a LifeForce thread, it is full of more questions on availability and trade-in details etc etc than on impressions of what the amp sounds like. This thread is for those who are interested in what the new LF sounds like and other auditioners/owners are encouraged to post their thoughts here.   (Apparently this was too subtle  )

Last week I was lucky enough to audition the LF55 in Hugh's system (which I know quite well) for a few hours and then in my own system for a few days. I have been using an AKSA 100N+ in my system for the last couple of years, since upgrading to it from a Plinius SA100 mk3 amp (100wpc, class A) that I bought several years earlier after it outperformed amps from Electrocompaniet, Perreaux, Rotel, Arcam, Musical Fidelity etc. My source is a Bolder modded SqueezeBox2 with Bolder Deluxe power supply (replaced my Sony SCD-XA777ES SACD player), pre-amp is a modded AKSA GK-1 (replaced a BAT tube pre-amp), speakers are modded Ambience Ultra 1600 SE's (with Hovland XO's). Room is 19' x 24' x 9' ceilings with a few room treatments.

Upon installing a new component I usually hear 2 or 3 major differences within the first few minutes then listen longer to ensure that these differences are indeed improvements, and to identify other less obvious differences. The aspects that first hit me with the LF55 were: bass; dynamic headroom/effortlessness; purity across the audible range; openness and imaging.

It was immediately obvious that this amp has plenty of grunt. Bass slam and detail were superior to the 55N+ and possibly even the 100N+. The palpability and detail of the bass was improved and we heard chords in the bass that were not noticed previously. The sense of the venue acoustic during dynamic orchestral passages was very impressive and there was no congestion or flattening of the imaging or soundstaging. The performance continued in a completely open and unhindered manner, very impressive. The LF55 gave the impression that it could knock down a brick wall just by breathing on it, a sense of power and majesty that is not evident from my 100N+ and gives the appearance of greater dynamic range. On one Mighty Sam McClain recording there are vocal peaks that audibly distort with the 100N+ and other amps. I had figured that it was on the recording given that it was my only CD that does this, but it is on an audiophile label and this seemed strange. However, played through the LF55 at the same or even higher volume, the distortion disappeared!

Strings and vocals are more lifelike than the N+ with a beautiful balance between the body and breathiness of voices. Percussion and guitar plucks are also better, their initial attack is cleaner and they float up more effortlessly in a quieter soundstage, sounding more pure and 'in the room'.

I have a couple of CD's that I don't tend to listen to very much as the female vocals are slightly bright and I find them irritating after a very short while. Again, I had put it down to the recordings. Again, the LF55 stripped away the brightness and hash to leave a wonderfully smooth, pure and beautiful voice. It does not do this by 'smoothing over' things, reducing transparency or giving up detail. Instead, it provides even greater transparency and detail, removing the slight hash and edginess that had caused irritation and hidden some of the detail and presence.

In a nutshell, the LF55 is a more refined sounding amp than the N+ with a wonderful transparency and a beautiful purity. No grain, no peakiness, just silky smooth and pure. The macrodynamic performance of a much larger amp, with the microdynamics, inner detail and poise more typical of a smaller one. The LF55 just disappears, leaving the performers in front of you, with palpability and presence I have not heard before (even from a $60k tube based system).

It is worth noting that my Ambience ribbon hybrid speakers, though excellent performers, are not the last word in dynamics. The fact that the LF55 was so impressively dynamic and effortless is therefore all the more impressive.

As good as the 100N+ was, hearing Hugh's flagship tube hybrid Glass Harmony monoblocks in my system revealed greater harmonic completeness and organicness, to a degree that I had never heard from a solid state or digital amp. My long term goal was looking like it would be a tube or tube hybrid amp .... not any more  ...  Bring on the LF100! 

EDIT: For completeness, I should mention that my early assessment stands:
AKSA stock amp   7.5/10
AKSA N+ amp       8.5/10
LifeForce 55 amp  9.7/10

I also forgot to mention that the LF55 does piano better than any amp I've heard, same for the realism of sticks and hands on drum skins.

Since my impressions above on the LF55, I have received my LF100 which now has approx 70 hours on it.

The LF100 sounds largely identical to the LF55, the only detectable difference being in the bass. The bass performance and quality of the LF55 surpassed the 100N+ (greater weight, impact, detail, control) and the LF100 bass is the same but with even greater impact and control .... it really is the proverbial iron fist in a velvet glove.

Initially I noticed a slight degree of edginess to upper mids and a slight over emphasis of sibilance. These traits disappeared before the amp had 30 hours on it and the music became even more open sounding, with quieter and cleaner space between performers, greater coherence and even greater inner detail floating up. The detail floating up from instruments deep in the soundstage on classical music is extraordinary. I was a little surprised that the amp settled down this quickly as I've known BlackGates to take much longer than this.

With the LF100 fully burned in, various recordings have taken on a dimensionality, transparency and organicness that I simply haven’t heard before. The sense of life and jump factor from this amp is truly outstanding. Tonality and timbre are superb! The sense of the 'iron fist in a velvet glove' is further enhanced with burn in. When we listen to bands at clubs there is a real weight to the bass lines that underpins or carries the entire performance and gives it a real sense of rhythm and life. Most stereo systems do not reproduce this feeling very well, leaving an unconvincing performance. The LF amps do this better than any I have heard, giving the performance a real (dare I say it  ) Life Force.

I've now played a wide variety of artists and genres, doing my absolute best to find even the smallest weakness. So far I have come up empty. The sense of front to back layering and the inner detail on instruments toward the back of the soundstage are top class. The imaging across the stage is now more coherent and the wall of sound presentation from the Ambience ribbon hybrids is the best I’ve heard. The music has more poise, the emotion and artistry just flow out effortlessly. It’s cliché  I know, but the system has disappeared and I’m just enjoying the performances. The suspension of disbelief is no longer periodically interrupted by artifacts that remind you that you are not at a live event. There is no conscious sense of listening to a tube or solid state amp, just real performances.

Perhaps I can finish with a sentence that I sent Hugh after burn in was complete ...

F@#K THIS AMP is GOOD!
 

[aurelius]

Me too... I placed an order for an LF55 this week!
Last night I had the pleasure of a visit to the home of AKSA and was given the privilege of hearing both the LF100 and the LF55.

Before I talk about the amps, let me qualify the discussion by stating that I now consider my Orions at least a class or two above any of the speakers Hugh had available for demonstration.  This is not to denegrate Hugh's set-up, but rather to highlight that there may be many strengths of the amp that I under-empasize, due to speaker differences.

In regard to the following aspects, the LF amps are clearly superior (LF + Hugh's speakers beats 55N+ plus Orion):

Preservation of decay: this is truely awesome.  Sounds fade from their peak to nothingness in perfectly textured natural decay.  As a result, environmental cues are much more realistic and the presentation of space is astonishing.

Sound Field: The aural image is substantially deeper, wider and higher.  Wall-to-wall, floor-to-ceiling; it's pretty magic stuff.

Mid-range tonal fidelity: I find voices a very difficult reference from which to judge tonal fidelity. Unless you intimately know the person singing (a la Dick Olsher's Leslie test), you can't possibly make a judgement; however, acoustic guitar is another matter entirely.  If one was well versed in these things, one could determine the wood of the sound board.  Whist no so practiced and estute myself, it was certainly a very engaging experience.

With regard to Mid range smoothness and effortlessness , the session gave me reason to believe that the LF is better than the N+, but speaker differences make it impossible to say for certain.

Specifically, one minor disadvantage of the N+ is the slightest propensity to make any midrange distortion in the original material stand out like dogs' balls.  Johnny Cash's version of Trent Reznor's "Hurt" off "Ring of Fire" is a fair exapmle.  The LF seemed to have relaxed the midrange without taking away any of it's dynamicism or musicality.

The area that most listners have noted to date is the bass slam.  I must confess that Hugh's speakers (with or without the Lifeforce) are a poor match for 2 x 10" Peerless XLS dipole woofers, equalised to 20Hz, 0.5Q, driven by 2 x 55N+. I can only go by what others have said.

As for the LF55 versus the 100, I will go against the tide and state a strong preference for the 55 for two reasons. 1) The sound field on the 100 sounded a little stretched for my taste... hard to explain, but it felt as though it were forced wide... some times it was as if I were wearing headphones... never experienced that with the LF55 which flowed effortlessly into its space. 2) Just a little more tonal elegance.  Swimmer or ballet dancer?  In a fight, you'd take the swimmer, but when beauty and grace rock your world, there is no comparison.

Would I part with the cash? If I had a simple stereo system, I wouldn't have walked out the door without slipping Hugh a lazy $750... as it is, I have a quad-amped system... do the math... it ain't pretty.  I suspect that I will upgrade one day any way... I'll just have to come up with more sophisticated marital cash laundering systems.

Cheers.

[ginger]

Well not really listening - the guys above have covered what it sounds like very well.
Now the LF55 Tech Head stuff:

Frequency response at 10W output (into a 3.5 Ohm resistor)
-3dB points at 8Hz and 82.5 kHz

Surprisingly I found that the frequency resonse at 1W, 10W and at 80W was nearly identical. That means that the amp is NOT slewrate limited. Probably where the great imaging (phase response) is comming from (also means no or low intermodulation distortion)

Max power (just below clipping), continuous sine wave, one channel ONLY driven, into 3.5 Ohm resitor load
80 Watts

10kHz Squarewave at 10W level into 3.5 Ohm resistor load - viewed on the oscilloscope showed single, well damped  half cycle of slight overshoot. This confirmed good high frequency response and good stability (into a resistive load at least). I should have added a capacitor across the load and checked this again but did'nt get around to it. Was busy listening to it again before it crossed my mind - it can wait for another day.

Cheers,
Ian

[AKSA]

Hi Ginger,

Many thanks for this technical information;  matches my measurements, though I'd not verified the power bandwidth, wow, much appreciated!

I've just had word from Rob White, a South African AKSAphile in Port Elizabeth who owns the AKSonics, a Swift, and now a LF55.  His comments are very interesting, and disclose a sharp audiophile with insightful things to say about the Lifeforce.  His email is reproduced here without change, with his permission.  What is so interesting is the complete consistency with things remarked upon earlier in this thread;  he picks up very strongly on the resolution, the warmth, the bass, and the sound stage. 

Hugh, I have listened to quite a lot of vinyl this weekend, and am convinced that this amp favours CD/DVD, unlike the 55N+ which favoured vinyl.  I have a lot of listening to do before I can honestly say that vinyl sounds better.  I am not convinced that the LF55 is run in yet, and I have a lot of AKSonic adjustments to make before I get the preferred position and settings.  The sound is natural and extremely detailed, more so than the 55N+.  The lows are more involved with extra grunt, so to speak.  There is definitely more separation from left to right and center stage is just lovely.  I have brought forward my sitting position slightly and this does help to surround me with or pull me into the sound.  It is a totally new listening experience and different to the 55N+, which is still in my memory, so I am comparing all the time.  At this stage I think the 55N+ is slightly warmer and valve like.  As I said the LF55 does need more time to settle in.

The LF55 is a classy amp and a totally new listening experience for me.  There is a lot of power there and detail at low volume is very impressive.  Quite seriously I don't think, at this stage, that anyone would need to consider bi or even tri-amping with the LF55.
 
In a nutshell, I think the LF55 is just great and satisfies all my hifi dreams, but I would never speak negatively about the 55N+.

Rob's comment about the relative warmth of the 55N+ is noteworthy.  The LF has a distortion spectrum around 15dB lower than the 55N+, and because I was gunning for extreme resolution in this design I did not engineer any H2/H3 into the signal as in the 55N+.  With less distortion, there was less masking required to eliminate the nasties, and the very clean, high resolution sound of the LF55 brings this out, adding a sense of intimacy due to the almost subliminal sound of the venue.  This in turn explains technically why Rob refers to the LF55 as a '...completely different listening experience'.  However, a little warmth is always a good thing for almost any SS amplifier, and this is the reason I like to see the LF55 coupled with a tube preamp, specifically the GK1/Swift.

Thanks Rob, this was a great rap, and I appreciate the time and effort you've gone to!

Cheers,

Hugh

[jules]

Putting all the reviews together we now have a clear and exciting picture of the new amps.

Hugh ... I hadn't realized that you'd got rid of the H2/3 engineering in the LF. That's quite a step and the fact that people are still talking "warmth" is a great credit to the design. For someone in Rob's position maybe a little tube rolling in his Swift could be interesting for vinyl but as he says, the LF isn't run-in yet.

Don't give yourself RSI with all that soldering Hugh 

Jules

[AKSA]

Hi Jules,

Thanks for the post - I think the word for the LF sound is 'intimate', whatever the heck that means.....  something like 'being there', for those Peter Sellers fans amongst us.   

The LF resolution is so fine that the notion of warmth is probably not relevant, given that in most 'warm' amps (read 'tube') there is usually an attendant loss of detail, however slight.  The LF detail is so evident, yet not aggressive, that you hear every nuance of the recording, including environmental cues and instrument and performance noises incidental to the music, but all at very low levels.  This gives a feeling of realism which I term 'intimate'.  This seems to more than compensate the need for warmth;  rather like freshly squeezed orange juice rather than sweetened, preserved concentrate (though this analogy is unkind to tube amps, some of which are just extraordinary!).

Rob nailed it, it's a totally different listening experience, and if anything the marriage with the Swift/GK1 is even more appropriate than for the AKSA.  The LF makes it possible to follow individual instruments in a small orchestra, for example.  I believe this is what is meant by 'seeing into the music'.  But as NP says, if you want it to sound like a tube, you use a tube.

The Swift/GK1 has that tube, but its distortion is kept very low as it is not used as a gain element, merely as an impedance transformer (a cathode follower, in fact).

The more I get into this technology, the more I think the amp should be utterly transparent and the preamp an analogue music processor, adding a little color to 'humanise' the sound.  By 'humanise' I mean somehow work on the music so that it grabs your heart - brings out the tingling spine and the tear to the cheek.  Of course, this cannot be measured, but you'll know it when you hear it......      I realise this is not purist, and many object, seeking the holy grail of low measured distortion.  But in a global feedback amp the distortions introduced are not musical as they are high order, massively objectionable the higher you go, and inevitable because of intermodulation through the feedback network.  So, the designer must either mask them with a smidgin of H2/H3, or banish them altogether from the power amp and add the 'organic' sound in the preamp - which is zero feedback, all Class A circuitry where distortions created are low order and benign musically.

I'm sure there are those who would disagree vehemently, let 'em eat cake I say, these are just my conclusions and I'm into what works, not religious argument!!

PS  Jules, I'm not too scared of RSI from all the soldering, it's the heavy metals that worry me.....  I might have my hair tested to see how much Pb I'm picking up from all that sniffing!!

Cheers,

Hugh

[ginger]

The LF resolution is so fine that the notion of warmth is probably not relevant, given that in most 'warm' amps (read 'tube') there is usually an attendant loss of detail, however slight.
....

The more I get into this technology, the more I think the amp should be utterly transparent and the preamp an analogue music processor, adding a little color to 'humanise' the sound.  By 'humanise' I mean somehow work on the music so that it grabs your heart - brings out the tingling spine and the tear to the cheek.  Of course, this cannot be measured, but you'll know it when you hear it......      I realise this is not purist, and many object, seeking the holy grail of low measured distortion.  But in a global feedback amp the distortions introduced are not musical as they are high order, massively objectionable the higher you go, and inevitable because of intermodulation through the feedback network.  So, the designer must either mask them with a smidgin of H2/H3, or banish them altogether from the power amp and add the 'organic' sound in the preamp - which is zero feedback, all Class A circuitry where distortions created are low order and benign musically.

I'm sure there are those who would disagree vehemently, let 'em eat cake I say, these are just my conclusions and I'm into what works, not religious argument!!

Hi Hugh,

A bit of a Quiche .. er Cake Eater Philosophy
I'm mostly in agreement with the above BUT am still a fan of the frequency dependent 2nd harmonic current distortion (ref Partridge) you get in a tube amp output transformer as the tubes output impedance approaches the impedance of the transformers primary inductance. That however is a VERY specific sound where you get significant 2nd harmonic distortion at low frequencies but that 2nd harmonic disappears at higher (fundamental) frequencies. This also limits "harmonic multiplication" (where the distortion products are themseves distorted and produce higher order distortion products again). From that point of view I like the final "sound" to be tailored in the TUBE power amp.

How I cope with this is that I modified the wiring in my GK-1 such that the HT bypass switch on the back now switches between:
Switch Up: Output taken directly from the volume control wipers (no tube buffer stage)
Switch Down: Output taken from the standard tube buffer output.

When I run a tube power amp I use the GK-1 with the switch up (Tube buffer out)
When I run the Lifeforce 55 I use the GK-1 with the switch down (Tube buffer in)

So - If you have enough time, money (enough for say 15 to 20 LF55s) and skills to prototype 3 or more tube amps then use the most basic preamp (maybe even a passive) and set the sound in the power amp.

Else use a Lifeforce to get that detail/energy/immediacy/image and tailor the sound in the preamp (GK-1 or other).This is certainly the most cost effective method to get to the sound you want.

The big caveat on all this is of course that speakers will always determine say 50% 'ish of your final sound   
or at least with an power amp of the quality of the Lifeforce they will. When we start talking about TUBE amps we necessarily have to talk about power amp / speaker combination and interaction.

Cheers,
Ian

[AKSA]

Hi Ginger,

Else use a Lifeforce to get that detail/energy/immediacy/image and tailor the sound in the preamp (GK-1 or other).This is certainly the most cost effective method to get to the sound you want.

No argument on this one!   I agree emphatically, and so continue to work on ways of processing the music so that the preamp gives this sound.

Thanks for the post, good points....

Back to ripping....

Cheers,

Hugh

[AKSA]

Folks,

I'm moving this back to the front page in the vainglorious hope that more LF reports/reviews come flooding in!!

Cheers,

Hugh

[Hegemony]

Hi all,

Just a quick update as I have had the LF55 in mysytem for many hundreds of listening hours now.  My system consists of SB3, Zhaolu 2.5 DAC modded with 2107 opamps and couple of other small mods, GK1, LF55 all playing through some Acoustic Energy bookshelf speakers that I picked up as an interim but never cease to amaze me with their ability although being smallish they do not let the amp do its full bass extension, which I have however heard on other speakers which were capable of a proper 35 hz or so.  For those who care I have average interconnects and cardas speaker cables.

The LF55 is one of only two items I have ever purchased that every time without fail when I use them I always say to myself "that is bloody fantastic", they always surprise me even though I know what to expect!  The other is my Kawasaki ZRX1200 motorcycle.  Even if I have just listened to my system a couple of hours ago, I am still often unprepared and surprised by unexpected depths of emotion from the amp.  This amp, especially with the GK1 just portrays music in the most fantastic ways.  (I also like listening to my motorcycle  )

I listen to a wide variety of music, classical, especially Paganini, lots of string compositions mostly, I love portishead, radiohead and some other more obscure Alternative/Triphop bands, I also love many genres of jazz, and also have a penchant for vocals like Jeff Buckley, Norah Jones, Eva Cassidy etc, Lastly I really enjoy almost anything accoustic.  So I believe I give the Amp a good wideranging workout.  I tend to listen to most of my music at about a realistic volume....give or take a bit.

The LF55 has an amazing ability to just play music!  I very rarely find myself wishing for something else.  I rarely think "that could have been clearer" or "that was not as dynamic as I expected".  It just seems to effortlessly do exactly a little better than I expected.  With the 55N+ there are places in many parts of the tracks I like where I would sort of hold my breath because the amp gave they impression it just might not quite make it (I am talking big dynamic transitions, or vocals like Jeff Buckley).  The LF55 is just effortless over these parts, it never hints it might struggle.  I find this adds immensly to my enjoyment of my music, I just know when I play the album it is going to be great!  It renders instruments and voice with an uncanny accuracy but is never harsh or tiring, to the contrary it is a pleasure to listen to entire albums.  Violins sound organic and alive with emotion as they do in real life, voices have edge and emotion.  The LF55 has a quality which I find hard to put into words and I have rarely heard on many other amps, something alive that allows the music to flow.

I have refrained from doing a particularly technical review here as this is not my forte'.  I do however read the other reviews and wholeheartedly agree with their comments on the LF from a more tech standpoint.  I really wanted to let people know that this is a really versatile amp that just effortlessly plays your music way above expectation all the time over many genres.  Compared to my 55N+ this is in a different galaxy all-together.  An amazing piece of equipment.

I am happy to audition this for anyone and wouldn't hesitate to recommend the LF to anyone looking for a very high quality product for a very reasonable price.  You will get more enjoyment out of this product than you possibly thought.

Thanks for reading this rambling review.
Russ

[DSK]

Russ, well said!

I sat here nodding as I read your post. Your following paragraph sums it up perfectly...

It just seems to effortlessly do exactly a little better than I expected.  With the 55N+ there are places in many parts of the tracks I like where I would sort of hold my breath because the amp gave they impression it just might not quite make it (I am talking big dynamic transitions, or vocals like Jeff Buckley).  The LF55 is just effortless over these parts, it never hints it might struggle.  I find this adds immensly to my enjoyment of my music, I just know when I play the album it is going to be great!  It renders instruments and voice with an uncanny accuracy but is never harsh or tiring, to the contrary it is a pleasure to listen to entire albums.  Violins sound organic and alive with emotion as they do in real life, voices have edge and emotion.  The LF55 has a quality which I find hard to put into words and I have rarely heard on many other amps, something alive that allows the music to flow.

I have about 175 hours on my LifeForce 100 now and all my earlier comments and observations still stand. I have just upgraded my speakers to a more transparent, refined, dynamic and articulate pair. The LF made it very easy to discern the differences between speakers and just lets the music flow without loss of emotion or beauty.

   aa 

[fajimr]

just installed my LF55 this evening and letting it settle in so I can test it....  give me a week and I'll let you know what I think

can't wait 

jim

[AKSA]

Hi Russ,

Very nicely put - thank you!  I must admit to worrying about the emotion thang;  the AKSA was designed, within the limits imposed by conventional topology, to convey warmth, like a tube amp;  the Lifeforce is a radically different approach, and I knew it would have an order of magnitude less distortion.  The absence of warmth might have been a concern to those who have listened to clinical amps, but the fact is the detail and resolution is now so fine that you absolutely hear everything.  Often excessive detail is an artefact of crossover distortion;  not so on the Lifeforce, where elaborate design steps were taken to remove all trace of this problem.  Thus, the detail is evident, making the amp 'intimate' in its rendition of the performance, but the fatigue is absent, because the usual high order distortions of crossover are banished.

Your comments are reassuring, thank you, and I certainly agree with you about the Kawasaki too!!  It's a stonking motor, very stable running gear, an absolute hoot to ride, even quietly!

Darren, I must visit very soon.....  thank you for your input.  Are your new speakers that much better than the ribbons?  That surprised me!!

Cheers,

Hugh

[SuperMart]

Hi Hugh,

My God man - what a way you have with words! I've been reading this thread wondering what I could possibly add given that I'm again in total agreement with all the other posters. And then you do it. Yes, indeed the Lifeforce truly is "inimate". Loads of my mates agree when I say to them "This amp is good inimate?".

All jokes aside, add me to the long list of very happy LF campers. I'm a 55er at present but I've got my name down for one of the retail LF100's in due course - can't resist having more of a very good thing.

I'm presently running Andyr's modded GK1 into it (thanks Andy - tell 'em what you've done to it -it sounds great) with a bog standard SB3 up front (analogue outs) and it's making great music. With 750 albums on Random Mix I've never had so much audio fun. Random Mix makes much better choices than I do.

Martin,

I'm very sorry - a spelling error!!  I have corrected it;  it should have been 'initmate', in the nature of convivial, rhetorical affirmation........    Hugh


Cheers,

[andyr]

With 750 albums on Random Mix I've never had so much audio fun. Random Mix makes much better choices than I do.

Cheers,

Well, SuperMart,

I guess SB "Random Mix" doesn't suffer from Alzheimers?      

Regards,

Andy

[Greg Erskine]

Hey Hugh,

With the number of LF/SB users here, have you thought of becoming a Slimdevices distributor or maybe a LF/SB package deal.

Looks like I'll have to upgrade my AKSA to fit in with the crowd.

I have to agree SuperMart about the "Random Mix", it certainly makes the decision easy, but do you select "Random songs" or "Random albums". 

regards