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Sound Practices Mailing List Files - Volume 2


=========================================================================
From: "Multi-Volti Devices" <multi-volti@softhouse.com>
Subject: [JN] 0.1 uF  450 v~ (that's vac) paper in mineral oil
Date: Mon, 19 Apr 1999 03:34:57 -0400
Source: Sound Digest Archive v02.n129

Hello:

I have some NOS Matsushita Industrial paper in mineral oil (labeled no
PCB's) capacitors, 0.1 uF 450 Vac. Ceramic body, fairly long leads. A friend
who is a capacitor applications engineer with a large film cap company
estimates a 'good quality' 450 vac part may have a DC rating as high as 1100
VDC. I am pondering how I can safely test these to estimate a DC rating.

I don't have access to a current limited DC hi-pot (dielectric withstand)
tester (only have access to an ac unit, which would just ruin the parts). I
was hoping I could observe leakage current at increasingly higher voltages
(analogous to diode reverse breakdown), and stop increasing voltage when I
start to get a change in IDC.

Any ideas on how to estimate the DC capability, and any ideas what would be
a fair (to me) price to sell some for? I have more than I anticipate
needing, but don't want to 'give them away' naively. I'd like to get a fair
price for them. (Roughly 60-70 left).

Thanks

Murray


=========================================================================
From: Remco Stoutjesdijk <remco@ultranalog.com>
Subject: [JN] 01 vs 26 ?
Date: Tue, 24 Apr 2001 15:27:58 +0200
Source: Sound Digest Archive v02.n873

Hi,

Whilst pondering a new preamp and trying to decide which tube to use, I
noticed the many similarities between the 01 and the 26. However while
the 26 is used in a lot of preamps, I hardly ever see the 01. Why? From
the datasheet it seems just a bit more fragile, but in preamps it should
work just fine. I have a pair of 301s that measure and match very well
and seem fine candidates for a nice WVOT preamp. Unless... well, I'm
curious why not!

Regards,
Remco
- --
http://www.ultranalog.com


=========================================================================
From: Jim de Kort <jim@vt52.com>
Subject: Re: [JN] 01 vs 26 ?
Date: Tue, 24 Apr 2001 17:05:02 +0200
Source: Sound Digest Archive v02.n874

Hoi Remco,

Whilst pondering a new preamp and trying to decide which tube to use, I
>noticed the many similarities between the 01 and the 26. However while
>the 26 is used in a lot of preamps, I hardly ever see the 01. Why? From
>the datasheet it seems just a bit more fragile, but in preamps it should

The 01A is very similar to the 30, Rp of 10K etc...




Jim de Kort
jim@vt52.com

http://www.vt52.com
http://www.ux226.com


=========================================================================
From: SBench@aol.com
Subject: Re: [JN] 01 vs 26 ?
Date: Tue, 24 Apr 2001 22:12:13 EDT
Source: Sound Digest Archive v02.n874

In a message dated 01-04-24 09:31:29 EDT, remco@ultranalog.com writes:

> Whilst pondering a new preamp and trying to decide which tube to use, I
>  noticed the many similarities between the 01 and the 26. However while
>  the 26 is used in a lot of preamps, I hardly ever see the 01. Why?

Hi,
In addition to the excellent notes also posted, I've found the 01A to be 
better
sounding than 26, but only when operated on reduced filament voltage.
(see distortion curves of 01A starved filament on my web pages
at http://members.aol.com/sbench101)

01A is sometimes harder to find, and it can be a bit microphonic, but
very nice sounding.

Best Regards,
Steve


=========================================================================
From: William Gardner <wg44929@mail.navix.net>
Subject: [JN] 025 sale
Date: Sun, 02 Jan 2000 23:29:30 -0600
Source: Sound Digest Archive v02.n559

For sale : Pair magnequest 025 OPT . New . $225.00
Thanks           William Gardner


=========================================================================
From: peufeu@free.fr
Subject: [JN] $0.5 cable recipe
Date: Fri, 22 Dec 2000 15:53:50 +0100 (MET)
Source: Sound Digest Archive v02.n768

    Hi people,

    This is a mad scientists' recipe for strange, yet interesting, audio 
cables :

    ingredients :
    - uninsulated plain standard copper wire from the junk pile (or strip the 
insulation from an insulated wire)
    - some of this PCB breadboard which you use for wrapping and making 
prototypes that smoke

    in the making :
    - cut small chunks of breadboard, rectangular pieces of about 1.5 cm. long 
and 3 mm wide (with just one row of holes in the middle).
    - cut your wire in 2 equal lengths, then thread the little PCB rectangles 
on it, using them as spacers to keep the two wires apart (put each wire in the 
holes at each side)
    - solder the wire to the breadboard pieces to make the thing hold together 
nicely

    Now you have two bare wires kept apart by little spacers. If you want a 
stereo cable, you can do it with three wires, with ground in the center of the 
spacers.

    Twist it so the wire pair does a half turn for every spacer (there should 
be one every 10 cm or so)

    Solder it to your favorite connectors and listen !!!

    I won't tell you how it sounds. It is interesting. Given the cost, I 
encourage everybody to try this and report your experiences on the mailing 
list...

    You can also do this with your speaker cables (no shieldong problems), your 
power supplies, etc...

    Have fun, and merry christmas !


=========================================================================
From: "Joerg Heyer" <joerg002@hotmail.com>
Subject: [JN] 0.5 F Capacitors (16V)
Date: Thu, 28 Sep 2000 16:14:22 EDT
Source: Sound Digest Archive v02.n677

Hi,

does anybody know a source for large value capacitators (o.33 - 1F) which 
are, *aehemm*, cheap (the schematic calls for 4 of them)?

Thanks Joerg
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=========================================================================
From: "David R. McGown" <dmcgown@megacats.com>
Subject: Re: [JN] 0.5 F Capacitors (16V)
Date: Thu, 28 Sep 2000 19:13:07 -0400 (EDT)
Source: Sound Digest Archive v02.n677

On Thu, 28 Sep 2000, Joerg Heyer wrote:

Try an shop specializing in automobile sound.  Here in the US, Parts
Express carries 1F capacitors as storage caps for high power custom auto
sound installations.  They have to be at least 12V.  Also, I think
Panasonic has some 1F 5V caps for computer power storage, if they are
cheap enough you can always use 3 in series to get 15V.  These are
available from Digikey.

David

> Hi,
> 
> does anybody know a source for large value capacitators (o.33 - 1F) which 
> are, *aehemm*, cheap (the schematic calls for 4 of them)?
> 
> Thanks Joerg
> _________________________________________________________________________
> Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.
> 
> Share information about yourself, create your own public profile at 
> http://profiles.msn.com.
> 

======================================================================
                            David R. McGown                               
dmcgown@megacats.com            -o-O-o-                     
 Home: (301)946-3027                             13100 Wilton Oaks Dr.  
 Work: (703)416-1240                           Silver Spring, MD 20906                              
   


=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] 0.5 F Capacitors (16V)
Date: Fri, 29 Sep 2000 09:26:03 +0200
Source: Sound Digest Archive v02.n678

Joerg

do you realy mean 1 F ? The only onesd I know are back ups for RAM memory.
These are 5.5 V, not cheap and I use them as back up in the backlight of
bikes....

Guido

At 16:14 28/09/2000 EDT, Joerg Heyer wrote:
>Hi,
>
>does anybody know a source for large value capacitators (o.33 - 1F) which 
>are, *aehemm*, cheap (the schematic calls for 4 of them)?
>
>Thanks Joerg
>_________________________________________________________________________
>Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.
>
>Share information about yourself, create your own public profile at 
>http://profiles.msn.com.
>
>
>


=========================================================================
From: "Joerg Heyer" <joerg002@hotmail.com>
Subject: Re: [JN] 0.5 F Capacitors (16V)
Date: Sat, 30 Sep 2000 14:36:02 EDT
Source: Sound Digest Archive v02.n681

Hi,

thanks for the help and suggestion!

Since finally taking a plunge at analog again, I settled on the Hiraga MC 
- -prepre for a starter for my (yet to order) Denon DL103.
The schematics can be found at the Bonavolt website
http://www.infomaniak.ch/~bonavolt/prepre.htm.

The caps 16V 0.5 F are for the battery power supply ( I like the idea of 
being independent of the power line, I hope to avoid electroexecuting me on 
my first non kit amp project). I will try other power supplies later but I 
wanted to start with a "original proven" design.

Joerg





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=========================================================================
From: "P. Caillaud" <peufeu@free.fr>
Subject: Re: [JN] 0.5 F Capacitors (16V)
Date: Sat, 30 Sep 2000 23:57:14 +0200
Source: Sound Digest Archive v02.n681

    Hi,

    If I can be of any advice, you don't need such a huge capacitance when
using battery power supply. Batteries are slow, but not to the point of putting
caps that can keep the amp running for several minutes once you unplug the
batteries... It looks like overkill to me.

    Having good quality caps is more important than having 1 Farad. I would
suggest low inductance 63000 uF types with MKP bypassing and anti-vibration
treatment (all caps are microphonic, some more than others).

    This will save you much dough, that you will re-invest at once in MAT-03
precision matched low-noise transistor pairs to replace the BC560C's. Overall
you should get much better performance from this.

    Good luck !


Joerg Heyer wrote:

> Hi,
>
> thanks for the help and suggestion!
>
> Since finally taking a plunge at analog again, I settled on the Hiraga MC
> -prepre for a starter for my (yet to order) Denon DL103.
> The schematics can be found at the Bonavolt website
> http://www.infomaniak.ch/~bonavolt/prepre.htm.
>
> The caps 16V 0.5 F are for the battery power supply ( I like the idea of
> being independent of the power line, I hope to avoid electroexecuting me on
> my first non kit amp project). I will try other power supplies later but I
> wanted to start with a "original proven" design.
>
> Joerg
>
> _________________________________________________________________________
> Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.
>
> Share information about yourself, create your own public profile at
> http://profiles.msn.com.

- --
_________________________

Pierre-Frédéric Caillaud
peufeu@free.fr
32 Passage Gonin
69001 Lyon
France

06 61 52 75 96
04 78 43 15 94

Tim Reese
reese@nmr.mgh.harvard.edu
MGH NMR Center
Charlestown Navy Yard
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Boston MA 02129