Pre-Amplifiers

[GKU]

Hi every body,

I'm new in this forum.
I needed a certain time to read the main threads of interest for me. There are a lot of them from which I have learned a lot and to which I would like to contribute to. But one thing has astonished me, there are only little projects on pre-amps.
Please don't kill me imediately if I start some provocative discussions.
Everybody is focused on power amps and talk about musically comparisons without mentioning the most important part in their chaine, the type of pre-amp used. Based on my personal experience, the pre-amp has much more influence on the musicality of a chaine as any modification of the power amp - type of resistors, capacitors, bi-polar or J-/MOS-FET's transistors etc. - .
Has some of you guys build ever the Kaneda pre-amp? I would like to learn about your experience - if any - and would like to exchange positive and negative experiences.
By reading other threads, I have learned that some of you are very experienced in Hiraga, JLH and Kaneda designs. Why not discussing the Kaneda pre-amp and solutions acquired.
I would very much appreciate any contribution.

Rgds

GKU

[icefox]

Hi there,

Given your are from Switzerland, I wonder if you are aware of any diy project that rival the quality of amplification electronics of FM Acoustics? Or it's base on the concepts of FM acoustics.

One mystery of FM Acoustics is that majority of its product are base on "balackbox" modules..... cannot see the circuit..

iCefoX

[GKU]

Hi icefox,

Unfortunately I'm not aware of any DIY pre-amp projects on the level of the Swiss-made FM-Acoustics equipment. They are very anxious to publish any information on their design.
But the main reason for their black-box design is less confidentiallity of their circuitry design but more to the reason to guarantee a homgenious thermal distribution and less thermal sensitivity of their device by casting the whole assembly with elastic epoxy casting resins. I assume they are using J-FET's in their entry part, which are very temp. sensitive.
In my previuos function as R&D director of a big Swiss chemical company I have been approached by FM-Acoustics for the development of such a casting resin with slightly improved thermal contactivity. Unfortunately the transistor markings have been removed thus I could not see which type of transistors they were using. Anyway even having these informations, due to a NDA between our companies I would be restricted to disclose any details.
For my self, I have build several years ago the Japanes pre-amp Kaneda for which I have build several PSU's and which I have compared on their impact on the sound and musicality, the reason for my post.
In addition I have the opportunity to compare this pre-amp with my recently acquired Audio Research SP 16 tube pre-amp. which use 12AX7 tubes. This pre-amp is in the USA one of the reference pre-amps. I can tell you, my last version of the Kaneda with a mix of battery and huge C's and regulated PSU sound very comparable to the AR.
Probably some other forum members are experienced with this design and would like to share their experience.

Rgds

Gerd