HDTenEightyP/NetNews huggingface dataset:
From: on@husc10.harvard.edu (Ahmad On)
Newsgroups: rec.audio.high-end
Subject: Re: FOR SALE: Pioneer A449 (A400 in UK)
Date: 19 Nov 92 14:47:47 EST
Organization: Harvard University Science Center
Distribution: rec
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

In article <1eg6t4INNsir@uwm.edu> e538-27@iti.org (Lim Kian Hong Allan) writes:
>I have a Pioneer integrated amplifier for sale. Its model number is A449. For 
>those who read the Uk audio magazines should heard of this award winning 
>amplifier.
>    It is call A400 in Europe and for the past few years have already won a lot
>of awards.
>
>    It is 60W/ch, with 3 lines, 2 tape, pre-in-pre-out(you can connect it to 
>an amplifier or a preamplifier), tone control, MC, MM, mute, head phone input
>and loudness.

Err..  I don't think that the A449 is the same as the award-winning
A400.  To the best of my knowledge, the A400 is a very minimalist
integrated amplifier and does not have tone controls or a loudness
button.  This was one of the reasons why it became such a huge success
in the UK.

-- 
______________________________________________________________________________
Ahmad Z. Che On                |        'I have the simplest of tastes...  
Harvard College '95            |         I am always satisfied with the best' 
on@husc.harvard.edu            |                                    Oscar Wilde
From: jrd@titan.ucc.umass.edu (J.D.)
Newsgroups: rec.audio.high-end
Subject: Need recommended source of parts for vacuum tube gear
Date: Wed, 18 Nov 1992 05:06:12 GMT
Organization: Univ. of Massachusetts - Research Computing Facility
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

Hello,

	I was wondering if there are any other people out there like me
that enjoy repairing and modifying tube based preamps and
amps... I havent touched a project in over a year and thus am kinda
rusty on where to get good components at reasonable (as opposed to
snobbishly overpriced) rates.

	Basically - I need a vendor that stocks a good selection of
quality film caps (polypro, polyester, mylar), high voltage
electrolytics, resistors, tube sockets and good vacuum tubes etc. Some
of these components are hard to find, especially in the +400 V voltage
domain ; most places around here cater to the low-voltage/digital
gearheads.

	I am not looking for the type of component vendors that sell
$90.00 gold-plated binding posts, or $40.00 ceramic tube
sockets - just quality gear, no BS..

	BTW - I am restoring a Leak Stereo 25 and also a Dyna Mark IV
but with the Curcio mods (triode-mode operation).

Thanks in advance!

...... J.D.
From: "Andreas G. Yankopolus" <ay0i+@andrew.cmu.edu>
Newsgroups: rec.audio.high-end
Subject: Re: ESL & Ribbon speakers?????
Date: Tue, 17 Nov 1992 17:01:15 -0500 (EST)
Organization: University of Wisconsin - Milwaukee
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          Tue, 17 Nov 1992 17:01:32 -0500 (EST)
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          Tue, 17 Nov 1992 17:01:16 -0500 (EST)
          via MS.5.6.pcs2.andrew.cmu.edu.pmax_ul4;
          Tue, 17 Nov 1992 17:01:15 -0500 (EST)
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Cc: 
Originator: tjk@csd4.csd.uwm.edu

An electrostatic speaker suspends a thin conducting sheet between two
charged metal screens.  The music signal from the amplifier is applied
to the sheet, altering the amount of charge on it.  Since there is a
strong electric field between the screens, the sheet vibrates, making
music.  Electrostatic speakers are usually coupled to the amplifier
through a transformer.  The intrinsic impedance of these speakers is
very high - most amplifiers cannot produce a high enough voltage to
drive them directly.  The transformer serves to step up the voltage from
the amplifier.  Even so, electrostatic speakers often have high
impedances and make a good match with tube amplifiers.


In a ribbon speaker, the "voice coil" appears in the form of thin metal
wires located in an insulating sheet.  The sheet is suspended in a
strong magnetic field created by large permanent magnets.  The signal
from the amplifier flows through the wires embedded in the ribbon.  The
moving charges in the wire and magnetic field interact to produce a
force on the wires and consequently move the ribbon.  Since the wires in
the ribbon provide the resistance to current flow, ribbon speakers
usually have very low impedances and usually require a high current
solid state design.


There are many reasons for the clarity of these designs.  The vibrating
sheet in an electrostatic speaker is very lightweight; Martin-Logan's
weigh less than a cubic inch of air!

Also, with both of these designs, the force is applied more or less
uniformly over the entire diaphram.  A dynamic speaker concentrates the
force in the center of the cone or around the perimiter for the dome.



Andreas Yankopolus
Carnegie-Mellon University
Junior, Electrical Engineering
From: jas@proteon.com (John A. Shriver)
Newsgroups: rec.audio.high-end
Subject: dcc
Date: Thu, 19 Nov 92 14:43:55 EST
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Cc: bhoughto@sedona.intel.com
Originator: tjk@csd4.csd.uwm.edu

I'm curious where DCC deck prices will go.  I'm sure that Philips is
barely covering the marginal cost of that first $799 deck, to mention
recovering the capital.  A loss leader.

The DCC heads will probably always be much more expensive than
Cassette heads.  Hell, Philips can barely have them made sucessfully
presently.  They use hard disk drive technology to make thin film
heads.  I don't know how long the heads will last.

I seriously doubt that people will really be willing to pay CD Prices
for pre-recorded DCC tapes for the DCC "Walkman".  I presume that the
nice non-offensive article failed to mention that DCC will have
EXACTLY the same retail prices as CD's, and will have the same lower
than LP royalties to the musicians.

Who can tell the difference between cassette and DCC through $7
headhpones?  Also, will DCC "Walkmans" be any better about not eating
the tape, which is uniformly the most miserable downside of cassettes.

THD readings on all digital recording media are done in such
artificial ways as to be totally irrelavant.  They are taken at full
volume, which is not where distortion is high.  They should be taken
at a more typical -40 dB level, where they will be much larger.

However, DCC may well have much better low level distortion than CD.
Both PASC (DCC) and ASTRAC (MiniDisc) use floating point numbers,
which is a much better way to store musical information.  You don't
have to sacrifice low-level resolution for dynamic range.  However,
the DAC in a DCC player is still 16-bit linear, the floating point is
just an input to the processor that de-compresses the data.

The jury is still out how how good the psychoacoustics behind the
compression algorithms are.  It may depend on the quality of your
equipement, and how intently you listen.  It will be hard to tell with
a Philips DCC deck, their analog design is usually totally inept.  The
NE5534's they use as I/V convertors after the DAC are totally
inadquate, but are probably they best they can buy in-house from their
Signetics division...
From: gasco!eeh@uunet.UU.NET (Eric Hutchinson x1589)
Newsgroups: rec.audio.high-end
Subject: Re: Cable TV Causes Stereo Hum
Date: Tue, 17 Nov 1992 00:52:01 GMT
Organization: Northwest Natural Gas Company of Portland Oregon
	id <m0mrHWN-000UNjC@qiclab.scn.rain.com>; Mon, 16 Nov 92 17:14 PST
	id <m0mrHAi-0009zRC@gasco.com>; Mon, 16 Nov 92 16:52 PST
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

In article <1e89heINNjsd@uwm.edu>, Scott Dorsey <kludge@grissom.larc.nasa.gov> writes:
> About all you can do about this kind
> of noise is to install an isolation transformer in the line so that the 
> shield of the TV set is floating with respect to the shield of the cable.
> Take two 75-300 ohm transformers (available for free from your cable TV
> office if you ask nicely) and tie the two 300 ohm sides together.  Connect
> the TV to one of them, then connect the cable to the other.  
> --scott
> 

This appears to work only if you isolate all of your cable connections.  I have
one incoming cable line that splits for *home run* conections to five locations.
Isolating the connection for the main tv still allowed the feed back to the 
stereo and vcr.  The only way around this appears to be isolating the main
incoming line before it splits to the five outlets.  All of the equipment shares
the same main ground and so each must be isolated if connected to cable.

Eric Hutchinson 				
eeh@gasco.com
From: chinh@sequent.com (Chi'nh Duc Dang)
Newsgroups: rec.audio.high-end
Subject: ESL & Ribbon speakers?????
Date: Fri, 13 Nov 92 16:56:07 GMT
Organization: Sequent Computer Systems, Inc.
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu


  I have a question for all Audiophiles in this newsgroup:  

    What is the major technical differences between Electrostatic and Ribbon 
    speakers, how do they reproduce music in the entire frequency spectrum, and  
    what make them sound so open, well defined, and details compared to 
    conventional cone speakers???????

  I have been subscribed to this newsgroup for quite sometimes and don't remember
seeing any question regarding to this subject.

  Thanks much

-- 

      Chi'nh Duc Dang
      Sequent Computer Systems, Inc.
        Internet: chinh@sequent.com  (503) 578-4235
From: peterca@ento.csiro.au
Newsgroups: rec.audio.high-end
Subject: Wima caps
Date: Mon, 16 Nov 92 10:44:03 EST
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

I am helping a friend to modify his Leak stereo 50 valve power amps.  He
bought these recently and the previous owner had done some changes (Mostly
not the ones I would have done).  One change I am unsure about is the
coupling caps from the phase splitter to the two output valves (KT66s). 
These are marked "Wima Durolit 0.22 630V".  Can anyone tell me what type
these are (poly-propylene/-ester/-styrene etc) and whether they are any
good.  Coupling to the phase splitter was changed to some cheap, modern
polyesters so I'm not sure whether the Wimas are original or whether the
previous modifier(s) were inconsistent in coupling capacitor choice.  

----------------------------------------
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)
----------------------------------------
From: peterca@ento.csiro.au
Newsgroups: rec.audio.high-end
Subject: Re: Need tonearm
Date: Wed, 18 Nov 92 10:07:30 EST
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu


>My brother-in-law has a Linn LP12, with the Valhalla
>power-supply, an older Linn Basik Plus tonearm (from his
>previous turntable), and a Linn K9 cartridge, he would like
>to upgrade his tonearm, and would appreciate any suggestion.
>His price range is under $500.
>
>He lives in Hongkong, and hasn't managed to find any shop
>that carries anything else other than SME, so he asks
>if I can find him a good new or used arm from the US.
I would suggest finding a Linn dealer.  Many LP12 owner may have upgraded
their arms to the Ecos which is an upgrade of the Ittok which is an upgrade
on the Basik.  Thus the dealer may be able to sell a used Ittok or point
you towards a customer who has one.  The LP12/Ittok/K9 is a good
combination which I used happily for several years before getting a much
fancier cartridge.  It also would put you in the position to either get the
most out of your K9 (which is nice) or upgrade cartridges later.

----------------------------------------
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)
----------------------------------------
From: BARRON@RHQVM14.VNET.IBM.COM
Newsgroups: rec.audio.high-end
Subject: Eton v. Focal
Date: Wed, 18 Nov 92 16:10:05 EST
Organization: Advantis Network Engineering and Planning
Reply-To: BARRON@RHQVM14.VNET.IBM.COM
NNTP-Posting-Host: 129.89.7.4
Disclaimer: This reflects the poster's views, not those of Advantis
Originator: tjk@csd4.csd.uwm.edu

I am desiging a system around the Accuton 211, 277 and an 8 in woofer
in a tall but slender ported enclosure.

My choice for woofer is either Eton 8-470 or 580 (whichever is the
long throw), or the Focal 8k-415s.   I will be crossing it over at
about 400Hz.

The Eton is on paper, more expensive, but much better low end response.

Is it worth the bucks? ($175 each v. $90 each).

I am looking for real experience with both.

Also...any comments on using a slim tall tower for the system; with
regard to dispersion, image, structure, etc.

The enclosure will probably be about 10" X 14" (deep) X 38".  I will
fill the lower few inches with sand, spikes, etc.  3/4" sides and
rear; 1.5" front and bottom MDF construction.
Mucho internal bracing, etc.
From: thk@tyres.asd.sgi.com (Tom Kong)
Newsgroups: rec.audio.high-end
Subject: Need tonearm
Date: 16 Nov 1992 04:24:10 GMT
Organization: Silicon Graphics, Inc.
Distribution: world
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu


My brother-in-law has a Linn LP12, with the Valhalla
power-supply, an older Linn Basik Plus tonearm (from his
previous turntable), and a Linn K9 cartridge, he would like
to upgrade his tonearm, and would appreciate any suggestion.
His price range is under $500.

He lives in Hongkong, and hasn't managed to find any shop
that carries anything else other than SME, so he asks
if I can find him a good new or used arm from the US.

Is there any stereo shop in the SF bay area that still carries
tonearms?  I haven't even seen a store that sells turntable
anymore in the last year or so.

Any suggestion is appreciated.

/tom
From: peterca@ento.csiro.au
Newsgroups: rec.audio.high-end
Subject: Re antique audio
Date: Wed, 18 Nov 92 18:02:24 EST
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

While agreeing with Dick Pierce that the speakers of the 1950s were made
without the benefit of the work of Thiele, Small etal. and as such were
necessarily a hit and miss approach, I'm sure some of the gear of the era
is worth salvage.  Specifically some amplifiers were pretty good.  I am
happy that my 1950s Leak 
TL12 is not out of place in my otherwise fairly modern system but I
wouldn't use the speaker or turntable it came with .  The one problem is
that it lacks power by modern standards even though my speakers are not
especially inefficient by modern standards.  The proffesional recording
gear and the disc cutting equipment must have been pretty good because
there is plenty of good sound on many 1950s LPs which I regularly play and
enjoy as much as modern recordings.  Perhaps the studio monitor speakers
were good enough to avoid making gross errors in the recording but weren't
good enough to hear just how good those recordings were (ditto for the
turntables).  My TL12 benefited from a large increase in power supply
capacitance which would have been impractically bulky at the time (and
other mods).  The design of crucial components like the output transformer,
however, must be sound for my mods to have yielded improvements.   
In the 1950s making watts in an amp was expensive and making an efficient
horn speaker was easy and you only had to accomodate one.  Solid state
brought cheaper watts and so you could afford to make smaller but less
efficient speakers which were easier for stereo placement.  It would seem
axiomatic to me that it is easier to make a good sounding small amp than a
good sounding big amp, all else being equal.  People are rediscovering the
good small 50's amps but having problems with their modern speakers.  What
I would like to know is whether (with the benefit of Thiel, Small elal) it
is now possible to make fully modern quality speakers with the efficiency
of the 1950's.  Such a speaker would be in demand from people like me who
have old amps.  I realise that I could get just as good or better sound
with buckets of power from any one of many high end marques but not for the
few dollars that my amp cost.  For the audiophile on a budget a tweaked old
amp is excellent value but for the problem of finding an efficient modern
speaker.  
What I'm hoping for is something equivalent to 90db/w/m with (say) 100W
(typical modern system).  Using my 12W amp, I would need around 99db/w/m. 
Are there reputable, quality designs for such speakers floating about which
a home constructor could try?  Will it necessariy be a horn?

----------------------------------------
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)
----------------------------------------
From: keivjam@elof.iit.edu (James Keivom)
Newsgroups: rec.audio.high-end
Subject: PROBLEM WITH CD PLAYER SKIPPING AT 30second mark
Date: Tue, 17 Nov 92 06:24:51 GMT
Organization: Illinois Institute of Technology, Chicago
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu



My roommate has problems with his CD player.  At the 30th second of the   
first track of the cd, it skips to another part of the selection.  it 
also skips if i try to cue forward at the beginning of the first track.
does anyone know why this is happening.  it deosn't happen in any parts
of the cd.  we tried cleaning.  

thanks

jim
From: clueless@cs1.bradley.edu (Matthew Simmons)
Newsgroups: rec.audio.high-end
Subject: Questions about recording formats
Date: Sun, 15 Nov 1992 18:27:16 GMT
Organization: J. Random Misconfigured Site
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

Can somebody help me find some background information for a speech?

I need to know the names of the inventors (companies or people, preferably
company names) of LP's, 8-tracks, and tapes....  (CD's were invented jointly
between Sony and Phillips, right?)....  I also need to know how an 8-track
works....  

Obligatory audiophile question:

	I just got the Stereophile Test CD I, and was listening to the 1st
musical track....  The one with the marching band.... Is that supposed to
sound horrible?  I mean, are they screwing up the song, or have I just never
heard it before?
From: jjb@halcyon.com (Jim Black)
Newsgroups: rec.audio.high-end
Subject: FOR SALE: Rotel CD player, Magnepan speakers
Date: Sat, 21 Nov 1992 19:37:10 GMT
Organization: Northwest Nexus Inc. (206) 455-3505
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

Rotel RCD-855 CD player 
   Bought Aug 91, still under 5-year warranty
   $270

Magnepan Magneplanar MG-1A loudspeakers 
   Reconditioned diaphragms, like new
   $450 pair

Also:
Pioneer Elite CLD-31 LaserDisc player
   Excellent high-end player w/ very low video noise
   S-Video outputs, coaxial digital output.  
   Plays all formats (LD, CD, CDV; 3", 5", 8", 12").
   Still under warranty
   $490 

Offers welcome...

- Jim Black       957 18th Ave E, Seattle WA 98112     (206) 324-6240
From: strong@tc.fluke.COM (Norm Strong)
Newsgroups: rec.audio.high-end
Subject: Re: Opinion on HK Citation II/III
Date: Thu, 19 Nov 1992 17:26:01 GMT
Organization: John Fluke Mfg. Co., Inc., Everett, WA
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

In article <1edhs3INNful@uwm.edu> henrylin@phoenix.princeton.edu (Henry Hung-i Lin) writes:
}
}what is the general consensus about the old HK tube gear? i'm looking into
}a Citation II/III amp/pre setup. how would it compare to newer solid-state
}models like Arcam, Creek, and Tandberg integrateds or an older Quad405?
}thanks for all help...

I owned a Citation II power amp for several years.  It was a 60 + 60
watt beast that weighed 60lbs and drew almost 300 watts of idling power.
Frankly, I didn't think it was so wonderful.  I got rid of it as soon as
decent solid-state stuff became available.  

(My power company sent a personal thank you note    :-)

-- 

Norm Strong  (strong@tc.fluke.com)
2528 31st S.   Seattle WA 98144   USA
From: Scott Dorsey <kludge@grissom.larc.nasa.gov>
Newsgroups: rec.audio.high-end
Subject: Cable TV Causes Stereo Hum
Date: Fri, 13 Nov 92 11:13:07 EST
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu


What's happening is that you are causing a big ground loop.  The cable TV
line is very long, and often improperly grounded, so you can expect to see
a lot of hum coming in on the shield.  About all you can do about this kind
of noise is to install an isolation transformer in the line so that the 
shield of the TV set is floating with respect to the shield of the cable.
Take two 75-300 ohm transformers (available for free from your cable TV
office if you ask nicely) and tie the two 300 ohm sides together.  Connect
the TV to one of them, then connect the cable to the other.  Expect a 4 dB
to 6 dB signal loss through this arrangement; if this is a problem you may
be forced to invest in a proper broadband RF transformer, but if your cable
TV company has a high enough level you should be okay.

Talking to the technicians at the cable TV company is usually futile.
--scott
From: "Peter Chong" <CHONGHGP@SGPVM1.VNET.IBM.COM>
Newsgroups: rec.audio.high-end
Subject: ESL and ribbons
Date: Thu, 19 Nov 92 10:30:15 SGP
Organization: University of Wisconsin - Milwaukee
   Wed, 18 Nov 92 22:48:40 EST
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

"Andreas G. Yankopolus" <ay0i+@andrew.cmu.edu> writes:


>In a ribbon speaker, the "voice coil" appears in the form of thin metal
>wires located in an insulating sheet.  The sheet is suspended in a
>strong magnetic field created by large permanent magnets.  The signal
>from the amplifier flows through the wires embedded in the ribbon.  The
>moving charges in the wire and magnetic field interact to produce a
>force on the wires and consequently move the ribbon.  Since the wires i
>the ribbon provide the resistance to current flow, ribbon speakers
>usually have very low impedances and usually require a high current
>solid state design.

What Andreas has described is a planar magnetic speaker. Magnepan
designs have single ended magnets. Whilst designs from Eminent Technology
have magnets on both sides.

A ribbon speaker uses a ribbon or strip of conductor (i don't know what
the material is) suspended in a field of large magnets at its sides.
Look at the Magnepan ribbon tweeter from the MG3s and Tympani. The
signal current is sent into this strip, and because the entire strip
is used to conduct, the impedence is very low. And presents a very
difficult load for the amplifier. To move a lot of air for bass, a lot
of strips are needed. And as a result a very powerful amp is needed to
drive the bass. Hence ribbon bass is not very practical till Apogee
refined the concept (some purists call Apogee designs as quasi-ribbon)
for full range operation...but then the original Apogees are hardly
practical to drive...with impedences at almost 1 ohm all the way...

Regards,
Pete

"I may be wrong, I often am, and am proud if it."