Hi all,
I am proud to say i've finished a Hugh's project once again. This was a particularly different journey, given i decided to dig up some treasures found in the attic , stored from past ages, but nevertheless one of the most fun to do ever.
I should start to say thanks to Hugh.R.Dean, as this is THE man.
He is behind all this, and of course i am mainly the workforce in a job where the brains is all that matters. Hugh has kindly given my support during this assembly, particularly hard thing to do from the other side of the world about a design thought more than 15 years ago. This is proof of Hugh's commitment to people and to his work. Praises.
So this is my GK-LIFEFORCE.
A tube-hybrid preamp and power amplifier built around a GK-1 and a Lifeforce 100.
I decided to join these 2 products together and mount them in the same chassis, however they are fully independent right down to their AC power input. Built from scratch, i had to source and buy just about every litle part.
It has the same look&feel of my previous designs in the past, right down to Hugh's signature on the front fascia. My tribute to him reamins. Kudos again and again
It features 3x inputs using an ELMA rotary switch and a ALPS 20K volume pot.
There is an independent AC filter conditioning ( FO-FELIX by FOLSOM ) for the GK-1 and the LIFEFORCE.
The Lifeforce was built with its power transistors flip sided so they can directly coupled to the large heatsinks that make up the chassis. This proves to be a very efficient solution, it barely warms up.
Chassis was built with a perforated steel plate separating the AC from DC side (more or less). AC side has filters, transformers and power supply. DC side has the power amp pcbs and the preamp board (split in 2
)
I plan to add little extra in the future. I use a raspberry pi + HAT DAC for source. As this is really small and i still have space inside the chassis close to the inputs i was thinking to built it as a 4th input. Only worried about possible wifi noise going into the tube sensitive preamp. Maybe someone can share experiences ?
Not bad for 6 months work? At least I am happy with it.
All the best
Filipe
I am proud to say i've finished a Hugh's project once again. This was a particularly different journey, given i decided to dig up some treasures found in the attic , stored from past ages, but nevertheless one of the most fun to do ever.
I should start to say thanks to Hugh.R.Dean, as this is THE man.
He is behind all this, and of course i am mainly the workforce in a job where the brains is all that matters. Hugh has kindly given my support during this assembly, particularly hard thing to do from the other side of the world about a design thought more than 15 years ago. This is proof of Hugh's commitment to people and to his work. Praises.
So this is my GK-LIFEFORCE.
A tube-hybrid preamp and power amplifier built around a GK-1 and a Lifeforce 100.
I decided to join these 2 products together and mount them in the same chassis, however they are fully independent right down to their AC power input. Built from scratch, i had to source and buy just about every litle part.
It has the same look&feel of my previous designs in the past, right down to Hugh's signature on the front fascia. My tribute to him reamins. Kudos again and again
It features 3x inputs using an ELMA rotary switch and a ALPS 20K volume pot.
There is an independent AC filter conditioning ( FO-FELIX by FOLSOM ) for the GK-1 and the LIFEFORCE.
The Lifeforce was built with its power transistors flip sided so they can directly coupled to the large heatsinks that make up the chassis. This proves to be a very efficient solution, it barely warms up.
Chassis was built with a perforated steel plate separating the AC from DC side (more or less). AC side has filters, transformers and power supply. DC side has the power amp pcbs and the preamp board (split in 2
)
I plan to add little extra in the future. I use a raspberry pi + HAT DAC for source. As this is really small and i still have space inside the chassis close to the inputs i was thinking to built it as a 4th input. Only worried about possible wifi noise going into the tube sensitive preamp. Maybe someone can share experiences ?
Not bad for 6 months work? At least I am happy with it.
All the best
Filipe
Bloody hell, Felipe, this is not what I was expecting!!
This is brilliant construction, I have to say that I could not do better, probably couldn't do as well, it is a masterpiece!!
You know, I built the GK1 as a kit. It was complex and almost destroyed me with the email support. There were three pcbs in it, as I recall, and a LOT of wiring. To manufacture it for retail took many, many hours and at the cost I could sell it - largely set by the low bar of the Chinese audio market - I could not make any profit from it. So I dropped the preamp and confined myself to my core skill - power amplifiers, which are more of a challenge intellectually. But some years later I was doodling on a napkin in a cafe and came up with a second version of the GK1, which I called the GK2.
The GK2 was a major improvement in refinement and musicality. I could not improve on the tube section, but completely revamped the SS section. I had a few pcbs made for it and released them over the next couple of years. If I make any more I will let you know of course!!
The Lifeforce design replaced the original AKSA, and represented my second major improvements to my amps. The feedback was completely changed, using nested feedback and reduced global feedback. The compensation was revisited. And the input stage, a simple long tailed pair, was rebuilt with complementary fb pairs, and the result was a huge improvement in clarity, bass power, and depth of image. From the Lifeforce I did the Soraya, another improvement, and then the Maya series, still my best amp and still in production.
Thank you for paying such wonderful homage to my older products, the Lifeforce and the GK1. I have said it many times, no one creates new topologies in audio, but we can refine existing technologies by rearranging stages around to create new products. That is the great pleasure of audio.
BTW, how do you find the sound quality?
Congratulations for such a wonderful achievement, Felipe!!
Cheers,
Hugh
This is brilliant construction, I have to say that I could not do better, probably couldn't do as well, it is a masterpiece!!
You know, I built the GK1 as a kit. It was complex and almost destroyed me with the email support. There were three pcbs in it, as I recall, and a LOT of wiring. To manufacture it for retail took many, many hours and at the cost I could sell it - largely set by the low bar of the Chinese audio market - I could not make any profit from it. So I dropped the preamp and confined myself to my core skill - power amplifiers, which are more of a challenge intellectually. But some years later I was doodling on a napkin in a cafe and came up with a second version of the GK1, which I called the GK2.
The GK2 was a major improvement in refinement and musicality. I could not improve on the tube section, but completely revamped the SS section. I had a few pcbs made for it and released them over the next couple of years. If I make any more I will let you know of course!!
The Lifeforce design replaced the original AKSA, and represented my second major improvements to my amps. The feedback was completely changed, using nested feedback and reduced global feedback. The compensation was revisited. And the input stage, a simple long tailed pair, was rebuilt with complementary fb pairs, and the result was a huge improvement in clarity, bass power, and depth of image. From the Lifeforce I did the Soraya, another improvement, and then the Maya series, still my best amp and still in production.
Thank you for paying such wonderful homage to my older products, the Lifeforce and the GK1. I have said it many times, no one creates new topologies in audio, but we can refine existing technologies by rearranging stages around to create new products. That is the great pleasure of audio.
BTW, how do you find the sound quality?
Congratulations for such a wonderful achievement, Felipe!!
Cheers,
Hugh
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Hi all,
I am proud to say i've finished a Hugh's project once again. This was a particularly different journey, given i decided to dig up some treasures found in the attic , stored from past ages, but nevertheless one of the most fun to do ever.
I should start to say thanks to Hugh.R.Dean, as this is THE man.
He is behind all this, and of course i am mainly the workforce in a job where the brains is all that matters. Hugh has kindly given my support during this assembly, particularly hard thing to do from the other side of the world about a design thought more than 15 years ago. This is proof of Hugh's commitment to people and to his work. Praises.
So this is my GK-LIFEFORCE.
A tube-hybrid preamp and power amplifier built around a GK-1 and a Lifeforce 100.
I decided to join these 2 products together and mount them in the same chassis, however they are fully independent right down to their AC power input. Built from scratch, i had to source and buy just about every litle part.
It has the same look&feel of my previous designs in the past, right down to Hugh's signature on the front fascia. My tribute to him reamins. Kudos again and again
It features 3x inputs using an ELMA rotary switch and a ALPS 20K volume pot.
There is an independent AC filter conditioning ( FO-FELIX by FOLSOM ) for the GK-1 and the LIFEFORCE.
The Lifeforce was built with its power transistors flip sided so they can directly coupled to the large heatsinks that make up the chassis. This proves to be a very efficient solution, it barely warms up.
Chassis was built with a perforated steel plate separating the AC from DC side (more or less). AC side has filters, transformers and power supply. DC side has the power amp pcbs and the preamp board (split in 2
I plan to add little extra in the future. I use a raspberry pi + HAT DAC for source. As this is really small and i still have space inside the chassis close to the inputs i was thinking to built it as a 4th input. Only worried about possible wifi noise going into the tube sensitive preamp. Maybe someone can share experiences ?
Not bad for 6 months work? At least I am happy with it.
All the best
Filipe
Brilliant work, Felipe!
And achieved in only 6 months. How do you like the Modushop Dissipante cases? I really do not like the way you have to use those right-angled brackets at the top and bottom of each heatsink, to attach the front and back panels. Unless you leave lots of room in the case ... it's impossible to get access to the bolts and nuts on the bottom brackets.
Andy
Hi,
Thank you for the comments, i have been wanting to post this for a few weeks but only got to take the pictures now.
Sound wise this is something i am already used to, been using Hugh's gear for some years now, first with the AKSA100, then LF55 and then Maya's.
I can honestly say that the LF100 is very true to its origins and a very fast action and articulated amp. It has as immediate foot taping movement into it and quite clean in voices and strings. Nice soundstage too.
The addition of the GK1 brings a mix of feelings. It tones down the sound a bit. I feel it rounds everything in a bubble, making it more forgiving in harsher recordings. It also detracts a little immediacy and soundstage too unfortunately. I think its like a cushion, you can easily listen to it all day.
For rock guitars and heavy Fender like solos i think i prefer Source to LF100 directly. But its a fair compromise, and it does add volume control and switches.
Maybe the GK2 brings this back ? I don't know, a project for the future maybe.
I have bought a couple of new tubes ( Gold Lion E88CC ) that i will try to see if i prefer them to the 6ES8 originals.
andy,
You are right, the modushop cases are nice to look at but a pain to work with.
I sticked to them because i currently have all my Maya's with the same chassis ( slimline modushop) and wanted to maintain the looks.
Here are is my Maya family:
Removing the back or front plate is horrid due to access to lower bolts. In my case, i have to remove the toroids first !! To do this i have to disconnect them to the PSU that shares a center tap for ground, aaarrrgghh....yuck!
So 6 months of engineering , 3 of which were fighting bolts !
Another obvious advantage of modushop is that they custom build the front and back fascia to whatever you like. So maintaining the Maya look was an obvious option.
I am quite happy on how it turned out.
Now to think on what to build next .... maybe Hugh can wave with a candy
Thank you for the comments, i have been wanting to post this for a few weeks but only got to take the pictures now.
Sound wise this is something i am already used to, been using Hugh's gear for some years now, first with the AKSA100, then LF55 and then Maya's.
I can honestly say that the LF100 is very true to its origins and a very fast action and articulated amp. It has as immediate foot taping movement into it and quite clean in voices and strings. Nice soundstage too.
The addition of the GK1 brings a mix of feelings. It tones down the sound a bit. I feel it rounds everything in a bubble, making it more forgiving in harsher recordings. It also detracts a little immediacy and soundstage too unfortunately. I think its like a cushion, you can easily listen to it all day.
For rock guitars and heavy Fender like solos i think i prefer Source to LF100 directly. But its a fair compromise, and it does add volume control and switches.
Maybe the GK2 brings this back ? I don't know, a project for the future maybe.
I have bought a couple of new tubes ( Gold Lion E88CC ) that i will try to see if i prefer them to the 6ES8 originals.
andy,
You are right, the modushop cases are nice to look at but a pain to work with.
I sticked to them because i currently have all my Maya's with the same chassis ( slimline modushop) and wanted to maintain the looks.
Here are is my Maya family:
Removing the back or front plate is horrid due to access to lower bolts. In my case, i have to remove the toroids first !! To do this i have to disconnect them to the PSU that shares a center tap for ground, aaarrrgghh....yuck!
So 6 months of engineering , 3 of which were fighting bolts !
Another obvious advantage of modushop is that they custom build the front and back fascia to whatever you like. So maintaining the Maya look was an obvious option.
I am quite happy on how it turned out.
Now to think on what to build next
.... maybe Hugh can wave with a candyUnfortunately, Gianluca is not interested in the different attachment arrangement (for front & back panels) that I suggested to him.
Maybe you should also write to him, Felipe, telling him of your difficulties with the current arrangement - if he gets enough comments about how bad the current setup is ... he might be moved to make it better!
Andy
Unfortunately, Gianluca is not interested in the different attachment arrangement (for front & back panels) that I suggested to him.
Maybe you should also write to him, Felipe, telling him of your difficulties with the current arrangement - if he gets enough comments about how bad the current setup is ... he might be moved to make it better!
Andy
Yes Andy, and i have. Also not only the front and back panels could benefit from better attachment. The handles he sells were horrid, now a little better but not good enough (i have swapped them for my own). He uses a predrilled front panel with only 1 spot for the handles. In my case i had to drill my own and got lucky enough that they did not collide with some other pre-drilled hole. I would prefer no pre-drilling.
IT is nearly impossible to build a sturdy case without the bottom steel plate (optional) and even then, the back plate is not well secured. IT clearly bends due to lack of support , i had to place some L plates to make them steady (on the Maya's and on this one too).
All in all, i still think they are beautiful chassis, and with the necessary adaptations it ends up with a nice sturdy build. If the front fascia could be removed with little effort, i could recommend them to everyone.
On a side note, i just bought a smaller alu chassis from the Chinese market for a fraction of the price, and not only it has equally impeccable visuals , it also features a super easy way to remove front or back panel !
No custom printing or engraving though.....what you see is what you get
On a side note, i just bought a smaller alu chassis from the Chinese market for a fraction of the price, and not only it has equally impeccable visuals , it also features a super easy way to remove front or back panel !
No custom printing or engraving though.....what you see is what you get
Nice, but the hole drilling & engraving is vital!
Andy