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Putpixel::Jacco Flenter

Marantz CD-63

Posted in Audio by Administrator on the August 3rd, 2006

It’s been a while since i’ve posted new stuff here. But that was because i was busy with other stuff then writing on this blog.

I’ve been mostly busy modding my father’s old Marantz CD-63SE cd-player. There’s a huge thread on DiyAudio.com about this (click here to see it). There’s tons of interesting information in it. And modifying the cd-player will give a huge improvement. In my opinion the most rewarding were: changing the powersupply for the indivdual parts of the player, changing the opamps (not because it was an extreme improvement but because i installed sockets so i could switch between 2 opamps and hear the difference). Mod’s that also made a big difference: removing the muting circuitry and bypassing the HDAM module.

How big is the difference? Well once i played a cd on my DVD-player for fun, but the songs i heard were soo different. Some instruments seemed to be hidden by the dvd-player which were clearly defined in the sound of the cd-player.

The bad stuff: unfortunately during my last attempt to upgrade the cd-player with extra regulators i seem to have caused a short somewhere in the player and thusfar i’ve been unable to fix that. I knew something like this would happen, my cd-player has been opened and closed tweaked modded and prodded at for hundreds of times now and it was starting to show. But one hell of an adventure, and certainly not something i regret… I’m just trying to find a cheap old marantz player for some extra modding :)

On last note: for all the people that have an old marantz lying around, the mod’s are also applicable to the Marantz CD-43, CD-53 and the CD-67. Which are all based around the same PCB (accept the CD-67 which is a later version of the 63 with differences in the PCB layout and the chips used etc).

Mosfet matching

Posted in Audio by Administrator on the December 5th, 2005

All right I must admit, it has been a while, but I have something I really think I should write about. Earlier this sunday I was working with my father on the circuit to match the IRF 9610 Mosfets for the Aleph-x when we were annoyed by the lack of precission of our measurement equipment. Until my father thought of the following schematic:
Matching schematic
The idea is to have 1 fixed/constant mosfet and measure the difference between this mosfet and the other mosfet (by measuring the difference between the Vgs).

Hoping to get some feedback on this idea I have posted it at diyaudio.com. That site is currently offline but I will post a link soon.

Silver interlinks

Posted in Audio by Administrator on the August 6th, 2005

A few weeks back I ordered some silver wire from ebay for use in my amplifier. I couldn’t wait however to build my own little interlinks. Using 2 x 4 strains with each 0.5 mm in diameter I created interlinks. Compared to my Xindak interlinks the placing of the instruments in stereo was better, unfortunately this came at the cost of too much treble. Like other silver interconnects I have heard at home, the detail is amazing. But listening to Miles Davis’s trompet play is very tiring and that’s not the way it should be.

Tommorrow I’ll try to see the difference between the silver interconnects i’ve build and my Xindak cables through an oscilloscope. Maybe I can pinpoint the problem and see if maybe the connectors that i’ve used on my interconnects are the cause of the problem (cheap used connectors I had lying around)

Audio update

Posted in Audio by Administrator on the August 6th, 2005

Well, not much news about the aleph-x, but it seems my next project a pre-amplifier for the aleph-x is starting to progress. The amplifier, called Balenced Zen line stage or Bride Of Son Of Zen is a design made by the famous Nelson Pass and the version I will build is modified to sound just that little bit better. The generous Nelson Pass designed this pre-amplifier to match the Son of Zen. The Zen series was designed by Nelson Pass to show people that simple designs can sound good and that it’s not that difficult to build a good sounding amplifier.

The original design can be found here
The thread that started the group buy for this design can be found here (PCB design/modification by diyaudio.com user Kari)


Posted in Audio by Administrator on the July 21st, 2005

Well, well… this blog seems to be updated weekly. Anyway, todat I’ve received the heatsinks and they look stunning! I had some difficulties because the delivery company could not deliver the package on a saterday. So instead of sending it to my home I had to send it to my work (which is almost one and a half hour by train/subway/walking). Good thing I do some exercise, these heatsinks weigh around 10 KG total

Heatsinks box Heatsink outside the box YAH-PHOTO(yet another heatsink)

Heatsinks ordered

Posted in Audio by Administrator on the July 14th, 2005

Well… I’ve payed for the heatsinks today, it amounted to around 198 euro’s. Fairly exceptable compared to Clofis’ pricing, but enough about that, I will try to find the time for ordering the PSU capacitors at Schuro (a company specialized in audio components located in Germany).

Rendering update

Posted in Audio by Administrator on the July 9th, 2005

A small update of the Aleph-X design. Now rendered in Blender and YAFRAY (Yet Another Free RAYtracer). This time with a sun as a lightsource instead of a regular spotlight. One thing I must say: I have problems with te lighting, the usual settings: 1.0 Energy for the lighting is not enough. I had to amplify this at least 5 times (which is not needed for Blender’s own renderer).

Heatsinks and case design

Posted in Audio by Administrator on the July 7th, 2005

Ok… What’s the status on the Aleph-X?
I never got a reply from deltour heatsinks, so I will verify the price and go for the Australian heatsinks. These are, however, slightly below my ideal heatdissipation (0,279 K/W each instead of 0,21 K/W) so I have to settle with a slightly less powerfull amplifier. It will still deliver 99 Watt at 8 Ohm with a peak of 117 Watt at 6.5 Ohm.

Because of the change of heatsinks I also redesigned the case (it’s still early design):

Here’s also a schematic of the powersupply: Schematic
The resistor represents the load of the amplifier, which in the simulations would amount to: 22 Volts @ 6.1A (which is more then I will actually use).


Posted in Audio by Administrator on the June 29th, 2005

Yesterday I queried about the prices of heatsinks, for I am building my own little (well, not so little) amplifier. The amplifier a Class A Aleph-X amplifier based on pattents by Nelson Pass and designed by user GRollins at diyaudio.com. Nelson Pass graciously allows users to build their own versions of his designs and actively supports this community. I’m going to build two mono amplifiers rated at 120 Watt Class A (which is a lot for this type of design) becuase of the ineffeciency of the amplifier, but it has a big advantage: they ought to sound great!

However what I wanted to say was this:
I needed 4 big heatsinks and queried at a company here in the netherlands (clofis.nl) for the right kind of heatsinks and was told they cost 145 euro excl. VAT (or BTW as we call it in Holland). Slightly taken back by the price I also queried at Conrad Heatsinks which is a company in Australia, similar heatsinks cost 139 euro for 4 of them. Which; including Fed-ex delivery; would set me back 195.7 euro and 4-5 day delivery time. The last company I queried (Deltour) has not yet responded, but is cheaper than Clofis (I hope), because I find it silly that buying around 10KG of heatsinks (including delivery) in Australia is slightly more expensive than buying a quarter of the amount in a city 15 KM from where I live (without delivery),

First post!

Posted in Uncategorized by Administrator on the June 24th, 2005

PutPixel has ceased to exist. Although it happened a while ago. I (Jacco Flenter) never got the patience to change the website.
Now I finally took the time to change it.

Let me explain what PutPixel was: a small company founded by Jacco Flenter a few months after he (or should I say I) graduated at the School of Arts Utrecht (HKU). The company was active for around 1 and a half years and after that it ceased it operations while I got a fulltime job at an Internet company. Like most of the freelancers who start working at an office job I welcomed regular paychecks and having collegues to expend your professional vision.

Enough about Putpixel. This blog will be used to express some of my interests and collect interesting links and news stories about my interests (which are interaction design, webdevelopment, programming, philosophy, audio, music and other stuff).