Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - Sigurd Ruschkowski

Pages: [1] 2 3
1
Headphone amplifiers / QRV-08 Headphone amp with current feedback and super ....
« on: November 22, 2005, 09:31:36 AM »
Looks awesome!
I like those many caps.

Could you take some close-ups, too?


Sigurd

Quote from: peranders
A snapshot of the pcb. Pictures with better quality will come. (the same camera but better lighting)


2
Headphone amplifiers / QRV-08 Headphone amp with current feedback and super ....
« on: November 22, 2005, 09:26:05 AM »
Good work!

Anything one should think about when assembling the headphone amp?


Maybe it is time to get some reference headphones, P-A?




Sigurd

3
Headphone amplifiers / QRV-08 Headphone amp with current feedback and super ....
« on: November 04, 2005, 05:26:32 PM »
Will be very interesting to hear about the sound quality!


Sigurd

4
Power supplies / High voltage, high current super regulator
« on: October 31, 2005, 11:51:24 AM »
A unit that can handle more voltage is interesting indeed!
More current is not necessary for me. About 300mA is max I need.
+-100V can be useful in the voltage gain part of a power amp  :)

Have you thought about a constant current shunt regulator?

I would like to see a + and - voltage regulated supply on the same PCB
and also to have dual channels on the same PCB, ie a 2x +- Voltage.

Transformers can be separate but it would be nice to have dual schottky rectifiers per rail and also the larger caps on the PCB  :D



Sigurd

5
Power supplies / JSR06, a complete super regulator
« on: October 27, 2005, 06:32:57 PM »
Excellent specs!
240 mA is more than enough fo my applications!

12V is what I will use for my amps.

On the photos above, you can see that I am using jumpers for R19 and E19 already. I guess that my using Schottky rectfiers will also help in getting a bit more raw voltage.

I got the transformers and heatsinks from ELFA today  :)



Sigurd

6
Power supplies / JSR06, a complete super regulator
« on: October 22, 2005, 02:55:58 PM »
My work on the JSR06s has started.

I am useing Schottky diodes instead of diod bridges.





Sigurd

7
Power supplies / JSR06, a complete super regulator
« on: October 13, 2005, 08:59:35 AM »
I have had some problems with the blue LED on my JSR03/05. Especially at higher output currents as you mention.
I am sucking 240 mA out of my JSR03/05 on a long time test as of now. I had to increase the input voltage by changing the transformer. No problems at all after 20h of testing :-)

I now have 33 V input to the ble LED +-24 VDC versions of my JSR03/05s and I have no problems taking out 240 mA (well cooled regulators of course!). 30V input did not work.

The latest and best OPamps today do not work with +-15V. I will be using +-12VDC for some AD8610. and AD825s and AD8065s.



Sigurd

8
Power supplies / JSR06, a complete super regulator
« on: October 13, 2005, 08:02:00 AM »
What a beaty she is. She = JSR06  :D

To see her in reality and not just as a PCB drawing makes her shine!

The mirrored layout is looks wonderful, Per-Anders.
You even made the heights of the transformer, caps, and heat sinks the same.

I look forward to building two units of this design!
Them I will use separate Schottky diodes instead of the rectifier bridge, and it even looks like you have made more space for all the 100nF caps, so I can put in the red WIMAs polypropylenes, or blue RIFA PFRs or 450s  :D  
Maybe a blue LED - if I use blue RIFAs or it will stay red if I use the red WIMAs.

Excellent work!


Regards,
Sigurd

9
Power supplies / Voltage reference in JSR03 regulator
« on: August 23, 2005, 01:05:13 PM »
Maybe I am thinking of an application where a TL431 is used as
a normal Zener diode and that this zener is supplying some kind of amp.

For such an applicaton I think that

* low noise over the audio bad

* low output impedande over the audio band

are the most important factors.



Sigurd

10
Power supplies / Voltage reference in JSR03 regulator
« on: August 20, 2005, 12:47:20 PM »
There is one voltage ref that according to my research
beats any other voltage reference:
OnSemi's TL431 BI/BV has extraordinary "audio" performance.

Check these data out and let me know if anyone found an other voltage ref that can beat the TL431 BI/BV.







Datasheet can be found at
http://coset.se/tmp/Audio/PerAnders/TL431B/TL431-D.pdf


Sigurd

11
Vinyl / Phono Preamp IC
« on: July 19, 2005, 09:31:57 PM »
Quote from: Marcos
Hi Sigurd!
Do you use one transformer for each channel?
Marcos


Always. For power amps and for other amps.

My latest line amp prototype power supply uses 200VA transformers for each channel, and each channel even has its own AC line filter.



On the LT schematics I would change the buffer to a 634 buffer instead.


Sigurd

12
Vinyl / Phono Preamp IC
« on: July 19, 2005, 10:54:36 AM »
!Ola! Marcos

The link to LT is not working for me,
but all the other links are OK.

I have bought two PCBs of the Bugle. Great looking PCB!
I have not installed any components yet. I do have most
of the OPamps I will try for the Bugle:
OPA2134
OPA627B (by using Brown Dog's adapater PCB)
Maybe the OPA745 or 743 as input OPamp.
Maybe the 8610?
8065?

I would try the same OPamps for the CM phono amps.

Even as important as the OPamps are the capacitors! Use the best you can afford. Polypropylene or polystyrene.

The Bugle PCB only has one power supply for both channels which I do not like. Use two separate PS if you can.

Sigurd - a high end audio person

13
Vinyl / RIAA network
« on: July 16, 2005, 07:05:58 PM »
I would say that the design of the passive or the active filter design and the chosen components affects the sonical quality in a major way.

Some say that passive is better with OPamps and active with discrete transistors.



Sigurd

14
Vinyl / Phono Preamp IC
« on: July 16, 2005, 07:03:07 PM »
Depends on the design.
Do you have a schematics?




Sigurd

15
Power supplies / JSR03 - information
« on: June 20, 2005, 08:48:55 AM »
Looks good on the photos.

Carbon fibre is really looking great! I am using it on my modell cars and boats.  My next preamp will also be in hardwood of some kind. Probably with an inner box of Al or copper plate/foil for shielding.
As a matter of fact, carbon fibre is conductive :-)


Sigurd

Quote from: Keljian
just a small update, I'm planning on a case similar to this one :

http://www.briangt.com/gallery/nigc-srmcgee

building it from scratch using carbon fiber, blackwood, aluminum and a few other things.. should come out really nice when it's done

Pages: [1] 2 3