HDTenEightyP/NetNews huggingface dataset:
From: johno@sdd.hp.com (John Ongtooguk)
Newsgroups: rec.audio.high-end
Subject: Re: Replacing Fuses
Date: 3 Sep 92 12:59:50 GMT
Organization: Hewlett-Packard, San Diego Division
Originator: tjk@csd4.csd.uwm.edu

In article <1992Sep2.130103.27927@uwm.edu>, tjk@csd4.csd.uwm.edu (Thomas Krueger) writes:
|> By now you've seen a couple advocates and a lot of people saying it's stupid
|> and dangerous to put larger fuses in place of smaller ones.
|> 
|> They're right, it's stupid.

   As I recall my amp had two sets of fuses; one for the primary section
   which you shouldn't bypass, as like you and others say it's stupid,
   and another set for speaker protection. Bypassing the speaker fuses
   is perhaps stupid, but since my gear seems to be very reliable 
   I'll take my chances, as it seems that the speaker protection offered 
   by fuses isn't reliable. 

   John Ongtooguk (johno@sdd.hp.com)        
Newsgroups: rec.audio.high-end
From: jumper@spf.trw.com (Greg Jumper)
Subject: Re: Software-based AD-Converters
Originator: tjk@csd4.csd.uwm.edu
Organization: TRW Sensor Data Processing Center, Redondo Beach, CA
Date: Thu, 3 Sep 1992 12:58:55 GMT

In article <1992Sep1.160934.13557@ifi.unizh.ch> hafner@ifi.unizh.ch (Michel
Hafner) writes:

     A few days ago I found a brochure of a company named "Theta".  They
     claimed to be one of three companies to offer software-based
     AD-Converters and the only one to do it right in every respect (
     frequency, phase, time..  ) ( the two others being Wadia and Krell,
     I guess ).  Is this claim unfounded or is the Theta Generation 3
     DA-converter really the best sounding unit around, better than
     Wadia, Krell, Accuphase etc.?  Anybody any listening experiences?

I won't comment regarding whether the Theta Generation 3 is "really the best
sounding unit around", since that is a totally subjective opinion.  However,
regarding the Wadia processors, just on general principles, I wouldn't
consider one, since Wadia is known for flying in the face of established
discrete-time signal theory.  (I.e., their software-based reconstruction
filter doesn't conform to the most basic requirements laid out in, for
example, Crochiere and Rabiner.)

I've heard Wadia and Krell processors, and the Krells sound better to me; I
also think many less expensive CD players (e.g., the Madrigal Proceed) better
the Wadia processors.  However, I was never seriously "auditioning" these
processors, so my statements are merely impressions developed while listening
for other things.

--

                                       Greg Jumper
                                       TRW Signal Processing Facility
                                       jumper@spf.trw.com


Newsgroups: rec.audio.high-end
From: fpf@gasco.com (Frank Ferguson x3584)
Subject: Armorall Incedent
Originator: tjk@csd4.csd.uwm.edu
Organization: University of Wisconsin - Milwaukee
Date: Thu, 3 Sep 1992 13:05:04 GMT
	(queueing-rmail) id 192834.23065; Wed, 2 Sep 1992 19: 28:34 EDT
	id <m0mQ2Q0-000Ok0C@gasco.com>; Wed, 2 Sep 92 14: 39 PDT

In a recent posting, the Armorall incedent was described as one
in which Stereophile readers were advised to use Armorall on their
record albums.  Actually, Sam Tellig (a Sterephile columnist) advised
readers to use Armorall on the CDs.  It turned out that Armorall is
probably not good for the CD material i.e. it causes deterioration in
the plastic.  Tellig was really pretty devastated by all this, in fact
it seemed like he might retire from the magazine as a result.  That
would have been a loss, he's a fun and informative writer.

Not that this is really important, but there it is.....

Francis P. Ferguson
fpf@gasco.com

My opinions, not my employers.


Newsgroups: rec.audio.high-end
From: chrisc@gold.gvg.tek.com (Chris Christensen)
Subject: Re: Replacing Fuses
Originator: tjk@csd4.csd.uwm.edu
Organization: Grass Valley Group, Grass Valley, CA
Date: Thu, 3 Sep 1992 13:06:14 GMT


In article <1992Sep2.130103.27927@uwm.edu> tjk@csd4.csd.uwm.edu 
(Thomas Krueger) writes:

>The benefit you get is not from putting a *larger* fuse in, just putting a 
>*new* fuse in. Or, if you don't want to buy new fuses, clean the end-caps
>off with a ScotchBrite (tm 3M) pad.

And while you are at it clean the fuse holder and put on a film of No
OX compound if you are interested in a stable oxidation free (and
safe) connection.

>Don't put larger values in. The size of wire in a 10A fuse is not
>significantly larger than in a 1A fuse, and you could kill someone when your
>amplifier starts on fire.

I fully support the above statement and I would suggest that if people
want a different fuse that *may* make a difference use a ceramic fuse.

I believe that the fuse element is crimped instead of soldered and the
material inside the fuse may drain off a few micro watts of heat and
reduce the IR drop a fraction.

I also like the idea of replacing line cords with heavier gauge wire,
but always replace the fuse with a value specified by the
manufacturer.

Oh and stop lifting those grounds!

-- 
Chris Christensen                  The opinions I express are my own,
chrisc@gold.gvg.tek.com            and sometimes they are wrong!
916-478-3419 FAX 916-478-3887      After all, I *AM* only human.

Newsgroups: rec.audio.high-end
From: jas@proteon.com (John A. Shriver)
Subject: Questions on Digital Cable
Originator: tjk@csd4.csd.uwm.edu
Organization: University of Wisconsin - Milwaukee
Date: Fri, 28 Aug 1992 13:03:02 GMT

   From: electron@waikato.ac.nz
   Date: 26 Aug 92 12:45:02 +1200

   In article <25AUG199200151523@zeus.tamu.edu>, p0p4018@zeus.tamu.edu (PREMTHAMKORN, PRAKIT) writes:
   > 3) Can I use ordinary cable as digital cable?  If not, why?

   I can't see any problem with using coax cable as long a you match
   the impedance of the input/output impedance of the equipment you
   are trying to connect together.  If the length of cable is not too
   long any cable will probably do.  (the lenth of a miss-matched
   cable can "round off" the sharp corners of the digital information
   and could produce errors.)  brucee

You really do want a good ipmedance match, and proper source and
destination termination, on a S/PDIF coaxial cable.  Since it includes
timing information that is encoded soley as the times of the zero
crossings of the signal, impedance mismatches would be bad.  They
would cause reflections, and reflections cause jitter in the zero
crossing times.  

For those of you who are up on networking technology, this is the same
reason as why you put Ethernet transceivers on the little black
stripes on the coax cable.  If you don't, you get more reflection and
jitter on the signal (same coding scheme as S/PDIF), causing clock
recovery to be worse.

This inreases the error rate on Ethernet, but that is becuase you have
in intermittent clock, and must acquire it in 64 bits.  S/PDIF has
continuous clock, so it's not as tough to extract it accurately.  I'm
sure that no digital cable is bad enough to cause S/PDIF decoding
errors, which is a good thing, since there is no data protection in
S/PDIF. 

However, there are arguments that listeners can detect picoseconds of
clock jitter into the DAC.  Data sensitive reflections on the S/PDIF
waveform can certain cause that.

However, one thing that has been in the press recently (one of Audio
Amateur, TAS, or HFN&RR I thin), or on this list, is that many
transports and DAC's have terrible S/PDIF impedance mismatches.  Ouch.
An advantage of AT&T ST glass fiber, no reflections, no media induced
jitter.

(The S/PDIF standard may also have contradictory requirements for
ground isolation and impedance matching.)

Newsgroups: rec.audio.high-end
From: jrb@uxv.larc.nasa.gov (Jim Branstetter)
Subject: Re: Questions on Digital Cable
Originator: tjk@csd4.csd.uwm.edu
Reply-To: jrb@uxv.larc.nasa.gov (Jim Branstetter)
Organization: FAA Office, NASA LaRC
Distribution: na
Date: Mon, 31 Aug 1992 13:13:46 GMT

with respect to john shrine and andy steen's articles on this
topic, i am curious as to whether the "length" of such digital
cables is critical ( as in the spacing of connections on the
ethernet cable).  i do recall when working on instrument landing
systems for the faa and in some broadcasting applications, the
"phase" or conversely, the physical length of the cable becomes
critical.  hence, i am wondering if the premade cables offered
by the manufacturers are actually cut to an optimal physical
length and multiples therof, such that the line reflections are
minimized for the particular frequency of the time code.

--
Jim Branstetter			jrb@uxv.larc.nasa.gov

Newsgroups: rec.audio.high-end
From: electron@waikato.ac.nz
Subject: Re: Questions on Digital Cable
News-Moderator: Approval required for posting to rec.audio.high-end
Originator: tjk@csd4.csd.uwm.edu
Organization: University of Waikato, Hamilton, New Zealand
Date: Wed, 26 Aug 1992 13:08:22 GMT

In article <25AUG199200151523@zeus.tamu.edu>, p0p4018@zeus.tamu.edu (PREMTHAMKORN, PRAKIT) writes:
> 3)  Can I use ordinary cable as digital cable?  If not, why?

I can't see any problem with using coax cable as long a you match the impedance
of the input/output impedance of the equipment you are trying to connect
together.  If the length of cable is not too long any cable will probably do.
(the lenth of a miss-matched cable can "round off" the sharp corners of the
digital information and could produce errors.)
brucee


Newsgroups: rec.audio.high-end
From: Ron Wilson <wilson@mml.ncsl.nist.gov>
Subject: Help with Cassette Decks
Originator: tjk@csd4.csd.uwm.edu
Sub-Organization: Computer Systems Laboratory (CSL)
Organization: National Institute of Standards and Technology (NIST)
Disclaimer: Opinions expressed are those of the sender
        and do not reflect NIST policy or agreement.
Date: Wed, 26 Aug 1992 13:10:57 GMT

Hello Netters,

I have some questions concerning cassette tape decks.   I have a old Pioneer 
that was top of the line in 1978.  It's one of the first (I believe) to offer 
Metal tape capability along with three tape calibrations (bias, eq, rec), 
and phase locked loop dual capstan drives, etc.  

OK, today I'm in the market for a new machine and I am thinking about getting 
a dual machine for use on tape trees.  I go to my neighborhood semi high-end 
audio store and the guy there tells me there isn't much difference between 
single and dual machines as far as the mechanism/design.  (I was wondering 
how they could be the same at the same price?)  I picked up some 
Sony info on their regular series and their ES series.  I looked at the 
specifications and noticed that 1) none of the dual machines offer closed 
loop circuitry which seems to reduce W&F from about 0.06/7 to 0.03 even 
though the single and dual machines use three motors and three heads.  
So my questions are:

1.  How important is this feature - will I here noise without it?  My old 
    machine had it.

2.  Has the technology improved so much that it's not really a problem?

3.  When I look at all the specs for the dual machines, the S/N ratio with 
    and without Dolby and metal tapes are the same for all machines, cheap 
    to expensive.  So am I just paying for features meaning the sound 
    will be all the same?  The W&F between the expensive and cheap machines 
    are from 0.08 to 0.07 to 0.06.

4.  Is it better to buy the highest end machine in the regular class or a 
    medium machine in the ES class?

5.  How important is a machine that has a super bias circuitry that operates 
    at 160kHz as compare to most machines at 105kHz?
    
6.  Since I only want a machine I can play a tape without hearing noise/hiss 
    will just about any medium level machine (~$300.) do?

7.  How important is it to have the third motor .vs. two and/or the third 
    head .vs. two?

8.  Do you recommend a particular brand or are they all about the same at 
    the same price?

I know I've asked a lot of questions but any help would be greatly appreciated.
I'm an old baby boomer who was really into audio back in the seventies and 
late sixties.  Now I pay more attention to video.  

Please help if you have time.  You can email me at wilson@mml.ncsl.nist.gov 
or post to the net.  Whichever you feel is appropriate.

Thanx,

Ron Wilson

Newsgroups: rec.audio.high-end
From: motoyama@harl.hitachi (Hiroshi Motoyama)
Subject: Re: Driving ELS Directly
Originator: tjk@csd4.csd.uwm.edu
Organization: Advanced Research Laboratory, Hitachi, Ltd
	<1684E7772.CCEB001@UTXVM.CC.UTEXAS.EDU>
Date: Thu, 27 Aug 1992 13:03:43 GMT
Return-Path: <motoyama@harlgw92.harl.hitachi.co.jp>


In article <1684E7772.CCEB001@UTXVM.CC.UTEXAS.EDU> CCEB001@UTXVM.CC.UTEXAS.EDU writes:

>In article <MOTOYAMA.92Aug24115800@harlgw92.harl.hitachi>
>motoyama@harl.hitachi (Hiroshi Motoyama) writes:

  >>Another bad point is that capacitive load magnified by transformers apt to
  >>make amplifiers unstable, indeed, it often causes oscillation.
  >>Typical capacitance of ELS is 3nF, and this is magnified by 10000(=100**2),
  >>then 30uF is an equivalent load when looked from the output end of an
  >>amplifier!
  >>
  >>Generally speaking, tubes are surly great for this purpose, but we can
  >>hardly find ones suitable for the spec, i.e. high-voltage, low-current use.
  >>All receiving tubes are too frail in voltage, and all transmitting tubes
  >>are too sturdy in current.

>You are not required to draw the full current capacity of a tube.  In fact,
>using a lower current would tend to extend the life of the tube.  

Good Mike, you are absolutely right in that this could extend the life of the 
tube. But this, at the same time, would absolutely reduce the life of yourself 
with annoying distortion:-). When a tube operates in near cutoff region, its 
linearity disappears. Transmitting tubes, especially direct heating triodes, 
show excellent linearity when properly used, i.e. several hundred milli-
amperes and several kilo-volts for tubes designed for 5kW radio stations.
But I do not want use them in that way for two reasons: economy and safety.

--
Hiroshi Motoyama                |   e-mail:  motoyama@harl.hitachi.co.jp
Advanced Research Laboratory    |   tel:     +81-492-96-6072 ext. 6233   
Hitachi Ltd.                    |   Sorry for reading such broken English,
Hatoyamamachi, Saitama, Japan   |   the commonest one in the World, though.

Newsgroups: rec.audio.high-end
From: root@maxed.amg.com (0000-Admin(0000))
Subject: FOR SALE: Krell and ROWLAND
Originator: tjk@csd4.csd.uwm.edu
Organization: American Micro Group, Inc., Ft. Lee, NJ
Date: Mon, 31 Aug 1992 13:13:53 GMT
	(queueing-rmail) id 214510.10585; Sat, 29 Aug 1992 21: 45:10 EDT

FOR SALE:

Krell KPB-64X DAC, latest mint and
Krell MD-10 transport, mint, the pair---$8500 firm

Rowland Model 7 amps, platinum, perfect, latest, $6200

Ed Whittemore   uupsi!maxed!ed   ed@maxed.amg.com
American Micro Group, Inc.   201-944-3293

Newsgroups: rec.audio.high-end
From: peterca@ento.csiro.au
Subject: Re: Component Matching
Originator: tjk@csd4.csd.uwm.edu
Organization: University of Wisconsin - Milwaukee
Date: Fri, 28 Aug 1992 13:03:30 GMT

I recieved the following comment re my component matching posting:

>Have you considered replacing the RC input capacitor with a smaller value?
>It probably won't hurt, especially if you don't have strong AM radio
>signals around that are going to come into the power amp via your cable.

Yes, Didn't I say that?  I meant to.  I reduced it about one third to
achieve the same filtering for a 3 fold higher R due to the
higher-than-usual output impedance of my preamp. 
My aim in this posting was to point out to some of the readers who may have
been confused that at least some component matching problems are due to
well understood and simple causes rather than something esoteric and
mysterious as seemed to be implied in some recent discusions.

----------------------------------------
Peter Campbell
C/O Div. Entomology, C.S.I.R.O.
Box 1700 Canberra A.C.T. 2601
Australia  (peterca@ento.csiro.au)
Ph.61-6-2464158 (w), 61-6-2516213 (h)
----------------------------------------


Newsgroups: rec.audio.high-end
From: bchall@tecnet1.jcte.jcs.mil
Subject: Interconnects and Speaker Cables
Originator: tjk@csd4.csd.uwm.edu
Organization: University of Wisconsin - Milwaukee
Date: Mon, 31 Aug 1992 13:12:54 GMT

I am currently in the market to upgrade the speaker cables and 
interconnects in my audio system.

I am looking to buy good quality cables without "breaking the bank."

My system consists of the following:

	B&K ST-140 Power amp
	Adcom GTP-400 Tuner/Preamp
	Rotel RCD-955AX CD Player
	Siefert Research Maxim III H Speakers

I would appreciate any comments/suggestions on reasonably priced 
interconnects (<$150 / pair) and speaker cables (<$200 / pair) that would 
go well with the equipment I have.

Thanks in advance!
Brian
--------------------------------------------------------------------------
- Brian C. Hall                              bchall@tecnet1.jcte.jcs.mil -
- Naval Air Warfare Center Aircraft Division                DSN 326-6120 -
- Patuxent River, MD 20670-5304                             301-737-6120 -
--------------------------------------------------------------------------


Newsgroups: rec.audio.high-end
From: <LLH111@PSUVM.PSU.EDU>
Subject: JPW address?
Originator: tjk@csd4.csd.uwm.edu
Organization: Penn State University
Date: Fri, 28 Aug 1992 13:03:46 GMT
   with BSMTP id 0497; Fri, 28 Aug 92 01: 53:35 EDT

Anyone know the address for JPW louspeakers, preferably in the U.S.?
Thanks.

Newsgroups: rec.audio.high-end
From: tomb@hplsla.lsid.hp.com (Tom Bruhns)
Subject: Re: headroom, what is 1.2db
Originator: tjk@csd4.csd.uwm.edu
Organization: HP Lake Stevens, WA
Date: Thu, 27 Aug 1992 13:02:52 GMT

lcoe@convex.com (Loren Coe) writes:

>how do you convert the 1.2db into watts?  is this the actual power
>it can sustain?  i suspect no, just only for some short duration, but
>what duration?

    dB = 10 * log (P1/P2)

    where P1 and P2 are two powers you are comparing.  If you are
operating in a system of constant impedance, this also can be
expressed as

    dB = 20 * log (E1/E2)  =  20 * log (I1/I2)

    where the E's and I's are voltages across and currents through
the load.

So rearranging,

    P1/P2  =  10^(dB/10)

For your 1.2dB example, P1/P2 is 1.32, or 132 watts peak for 100 watts
continuous.
From: yoda@deathstar.stanford.edu (Terry Lee)
Newsgroups: rec.audio.high-end
Subject: Re: Interconnects and Speaker Cables
Date: 4 Sep 92 14:08:55 GMT
Organization: Residential Computing, Stanford University
Originator: tjk@csd4.csd.uwm.edu

In article <9208281910.AA25416@tecnet1.jcte.jcs.mil> bchall@tecnet1.jcte.jcs.mil writes:
>interconnects (<$150 / pair) and speaker cables (<$200 / pair) that would 

You've got to be kidding.  Save your money and by a Nakamichi pure copper,
foil shielded interconnects at $20/pair and just keep you speaker cables
as short as possible with any high quality, reasonably price speaker
cable.  I challenge you to do a double blind test and figure out what
sounds better.

Cheers,

Terry Lee
Newsgroups: rec.audio.high-end
From: rmg53668@uxa.cso.uiuc.edu (Ryan M. Grant)
Subject: Re: CD players, are they all the same ?
Originator: tjk@csd4.csd.uwm.edu
Organization: University of Illinois at Urbana
Date: Wed, 26 Aug 1992 13:10:21 GMT
  (5.67a8/IDA-1.5 for <rec-audio-high-end@ux1.cso.uiuc.edu>); Wed, 26 Aug 1992 04: 23:14 -0500
  (5.67a/IDA-1.5 for rec-audio-high-end@ux1.cso.uiuc.edu); Wed, 26 Aug 1992 09: 23:21 GMT

rsud@lectroid.sw.stratus.com (Rajiv Sud) writes:

>Seek out the latest issue
>of 'The Absolute Sound' and you will find an article that discusses why
>transports as well as d/a converters are different.

I'd love to do this, but fear it is not sold anywhere nearby - or I would
	have already noticed it while reading the others.  Is there any way
	you could post (or email) a summary?

			Thank you,
			- Ryan Grant
Newsgroups: rec.audio.high-end
From: CCEB001@UTXVM.CC.UTEXAS.EDU
Subject: Re: Driving ELS Directly
Posted-Date:  25 Aug 92 14: 29:22 GMT
Originator: tjk@csd4.csd.uwm.edu
Organization: The University of Texas at Austin
Date: Wed, 26 Aug 1992 13:06:32 GMT


In article <MOTOYAMA.92Aug24115800@harlgw92.harl.hitachi>
motoyama@harl.hitachi (Hiroshi Motoyama) writes:
>Another bad point is that capacitive load magnified by transformers apt to
>make amplifiers unstable, indeed, it often causes oscillation.
>Typical capacitance of ELS is 3nF, and this is magnified by 10000(=100**2),
>then 30uF is an equivalent load when looked from the output end of an
>amplifier!
>
>Generally speaking, tubes are surly great for this purpose, but we can
>hardly find ones suitable for the spec, i.e. high-voltage, low-current use.
>All receiving tubes are too frail in voltage, and all transmitting tubes
>are too sturdy in current.
 
You are not required to draw the full current capacity of a tube.  In fact,
using a lower current would tend to extend the life of the tube.  This
scheme would require the amp and speaker to be codesigned to work with
each other.  The audiophile community will not stand for an approach so
brutally rational.  It would reduce the available permutations too
greatly.
 
The not so audiophile community, is not too impressed by the need for
vaccum tubes or electrostatic speakers.  Speakers with matched amps are not
too popular with any class of consumer except as a walk thing accessory.  It
is a shame too.  A speaker with an electronic crossover and individual
ic amps for each driver would cost very little more than speakers with
passive crossovers and separate power amps.  It would eliminate toasted woofers
from overpowered amps, toasted tweeter from underpowered amps, simplify
crossover design, eliminate problem with relative driver efficiency, eliminate
problem about how many speaker an amp can drive, get the hot power amp away
from the rest of the system, and largely eliminate flame wars about speaker
cable.  They might even sound better.
 
Mike.Coyne@utxvm.cc.utexas.edu
From: electron@waikato.ac.nz
Newsgroups: rec.audio.high-end
Subject: Help, passive crossover wanted!
Date: 31 Aug 92 13:15:55 GMT
Organization: University of Waikato, Hamilton, New Zealand
News-Moderator: Approval required for posting to rec.audio.high-end
Originator: tjk@csd4.csd.uwm.edu

I have made a set of speakers using Vifa drivers.
My system consists of -:
a Vifa 10 inch mineral filled polycone woofer
a Vifa 3 inch dome midrange
a vifa 1 inch dome tweeter.
These are all packaged in a 55 l bass reflex cabinet.
At the moment i a running them active with a series 5000 mosfet amp on the
bass, and for the mid and tweeter, some HY 60 amplifiers from Radio spares.
I would like to know if anaybody out there has a circuit diagram for a passive
crossover for the above drivers.  If so could you pleeeaaase e-mail me so i can
get more details from you. ie scan, uuencode and mail the circuit to me.
ta much
Bruce Rhodes
University of Waikato
Hamilton
New Zealand.
From: KLUDGE@AGCB1.LARC.NASA.GOV
Newsgroups: rec.audio.high-end
Subject: Comments on ST-70
Date: 28 Aug 92 13:01:25 GMT
Organization: University of Wisconsin - Milwaukee
Originator: tjk@csd4.csd.uwm.edu


I can't comment on the Panor copy of the old Dynaco ST-70.  I can, however
comment on the original ST-70, and I can say that frankly the ST-70 wasn't
that good an amplifier.  That's why some of the audio magazines may not be
terribly gung-ho about the thing.

The ST-70 was inexpensive, and had good output transformers.  For this
reason it was a popular starting point for homebrew amps and modified
versions, some of which sounded excellent.  The original, unmodified ST-70
wasn't terribly hot, though (and frankly I don't think much of the 7199
anyway, and wouldn't even if it were readily obtainable).

If you want an ST-70, there are plenty of them out there and they aren't
expensive.  I've got a couple of them holding up a stack of books somewhere;
I keep meaning to sell them while the prices are rising.
--scott