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Old 10th May 2013, 07:36 AM   #141
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I am in Munich but i will now see Willibald Bauer in his shop.
Later this afternoon i am at the MOC.
I could come to your booth at ca. 16.00.
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Old 10th May 2013, 08:05 AM   #142
grufti is offline grufti  United States
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Quote:
Originally Posted by Calvin View Post
Hi,

Alfred and Joachim. Where are You at the show? I liked to drop by and say hello, or you can visit me at booth C06 in Hall3 and see the future *lool*

jauu
Calvin

What is your "future"? I assume it's out in public at the show and you can talk about it.
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Old 11th May 2013, 04:49 AM   #143
Calvin is offline Calvin  Germany
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Hi,

CD is dying! It's reinage comes to an end. Streaming solutions are taking over.
But while streaming clients are poppping up at every corner, there are only a few server systems which can do away with the inherent problems and deficiencies of Client-Systems. And I'm quite proud to say that we can offer one of the most refined if not The most refined Music servers at the time under our label purist and as OEM-solutions.

jauu
Calvin

ps. and now back to topic
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Old 11th May 2013, 08:00 AM   #144
gk7 is offline gk7
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As someone how works in the IT industry Iīm always astonished how such "solutions" which "do away" with (unidentified) "inherent problems" are sold to customers while providing services which can be implemented with commodity hardware and some open source software at a fraction of the price.
But nevertheless, good luck with your business.
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Old 12th May 2013, 05:51 AM   #145
Calvin is offline Calvin  Germany
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Hi,

as someone who motor bikes I'm always astonished how such "solutions", as for example special tires, are sold to customers while providing services which can be implemented with any wheel as long as its round and cheap.
As ITist You will know that a good software is not the software that offers functionality, but one that the user can work with best.
Most customers in HiFi are no ITist, nor do they want to deal with "computer issues" whatsoever in their free time. They don't want computer stuff in their living room and most certainly no piles of technical devices crammed side to side to their TV screen and flower pots. So the user interface needs to be as intuitive and simple as possible, as must be the setup and handling of the devices. This is certainly not the case with open source software and a pile of hadware.
Or as VW says in an actual advertising of the Golf GTI:
"often copied, never equaled"

jauu
Calvin

ps. thanks alot for the good wishes ;-)
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Old 12th May 2013, 07:22 AM   #146
gk7 is offline gk7
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Well, ok thats a point. BTW especially as an IT guy I donīt want to deal with computer
issues in my free time ;-)
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Old 12th May 2013, 02:04 PM   #147
hesener is offline hesener  Germany
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Quote:
Originally Posted by Calvin View Post
....... most certainly no piles of technical devices crammed side to side to their TV screen and flower pots....
well, thats not true for me (to the despair of my wife )

but your point is absolutely valid, I think. I just put a mountain of CDs aside that I am no longer listening to. A whole bunch is on the server, as MP3s..... Need to find a good solution for high-res.....
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Old 13th May 2013, 09:03 AM   #148
Calvin is offline Calvin  Germany
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Hi,

Then we need to talk Alfred

jauu
Calvin

ps. The show's over since 0:30 tonight. Now the show must go on!
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Old 21st June 2013, 05:25 PM   #149
Calvin is offline Calvin  Germany
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Hi,

as the question arose in the Paradise thread about the possibility of creating a SE-to-Bal Converter using the Calvin Buffer, I suggested to possible solutions under useage of two Calvin-Buffers. First is to put a simple inverter stage ahead of one of the buffers and the second was to put a fully differential stage ahead of the buffers.
Since a fully differential stage offers more flexibility Iīd like to concentrate on that one.

jauu
Calvin
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Old 21st June 2013, 05:54 PM   #150
Calvin is offline Calvin  Germany
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Hi,

in a simple form the fully differential stage may look like the left circuit.
The relationship between drain and source resistors defines the gain.
THD of such a stage is rather high at >0.1% (-60dB and higher) but with a nicely falling harmonic distribution.

Cascoding the JFET doesnīt improve THD significantely but reduces maximum output voltage which is already low with supply voltages of +-15V.

Things change to the better if we use a CFP like the circuit to the right instead of the single input transistors, for example a JFET-Master controlling a bipolar PNP-Slave, similar to the Calvin-Buffer. This reduces THD by up to 30-40dB against the simple stage, thereby preserving the good THD-Values of the Buffers. The improvement is due to a vastly reduced signal current amplitude through the JFET, since the bipolar slave takes over most of the current swing. At the same the connection of the JFETīs source with the bipolarīs collector closes a very short current feedback loop.


jauu
Calvin
Attached Images
File Type: jpg differential JFET gain stage principle.jpg (17.8 KB, 445 views)
File Type: jpg differential hybrid CFP gain stage principle.jpg (21.1 KB, 447 views)
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