HDTenEightyP/NetNews huggingface dataset:
From: znpt01@trc.amoco.com (Norman P. Tracy)
Subject: Re: Planars and stuff...
Originator: znpt01@gpss43
Organization: Amoco Production Company, Tulsa Research
Date: Fri, 18 Dec 1992 19:58:01 GMT


In article <1992Dec18.031739.9411@tc.cornell.edu>, stevan@alchemy.tn.cornell.edu (Stevan Vidic) writes:
> 
> The other more troublesome issue is that ribbons are very delicate and
> do not last a long time.  They also degrade sonically with time.  My
> friend bought a 1-year-old demo pair from a dealer and after about 3
> months one of the ribbon panels died.  He called the dealer and sure
> enough since the speakers were under warranty the ribbon was replaced
> free of charge (came really neatly packaged).  But then (get this!) my
> friend realized just how lousy the corresponding panel on the other
> speaker was.  By setting the sound to mono and switching between the 
> two speakers it became painfully obvious that the old ribbon was dark 
> and muffled.  He took the cloth off and looking from the side noticed
> that the ribbon (which is BTW unbelieavably thin) has a couple of
> ridged areas almost like wrinkles, unlike the new ribbon that was
> perfectly flat.  So he called the dealer to come take a look at that
> and dealer said he'd call Magnepan and get another replacement panel.
> 
> 
> Regards,
> Stevan
> 

What Stevan says is correct only for true RIBBON speakers.  This term (like
many others in audio) is ratherly loosely used so let me define it.  A true
ribbon speaker is a sub-class of planers where the entire diaphragm is made
out of very thin metal foil.  The only examples of these I know of are the
Decca and Sequera tweeters and the tweeters in 'R' series Magnepans.  Most
other planers refered to as 'ribbons' are in fact what I call hybrid-ribbons.
In these the foil or wire conductor is bonded to a plastic diaphragm which
gives it strength.  True ribbons suffer from metal fatigue and need to be
replaced every few years as Stevan's story relates.  They are also so thin
that they break or act like fuses when over driven.  Hybrid-ribbons, because
of the plastic backing, do not suffer these failure modes.  This accounts in
part for their popularity with Carver, Magnepan (for mids, woofers and some
tweeters) and Apogee.  Like all engineering each method has its strengths
and weaknesses.  The true ribbon more closely approximates the ideal, the
hybrid seems to be easier to make into a real product.

Norman Tracy
znpt01@trc.amoco.com
From: kirk@hpcc01.corp.hp.com (Kirk Lindstrom)
Date: Mon, 14 Dec 1992 21:05:36 GMT
Subject: Re: long patch cord TV-to-receiver ?
Organization: Shredding the water of SF Bay, HP-OCD
Newsgroups: rec.audio

Try a cheater plug on the TV (i.e. don't hook it to house ground).  Also, one
side of the shield on the cable MUST be tied to a ground else the shield does
more harm than good (serves you right for listening to a RS "expert").

There is a box called IDOS for $150 that may help also.  Also try computer
emi/surge supressors.  I had similar problems with short runs of wire and
managed to fix it by isolating grounds in a self modified emi/surge protector
box.

Please post your results.

Kirk out
=> "We are what we pretend to be."  -  Kurt Vonnegut Jr.
+---------------------------------------------------------------------+
| Kirk Lindstrom - OCD Product R & D | Hewlett-Packard Co.  M/S: 91UA |
|   Engineer/Scientist, Hardware     |                                |
|------------------------------------| Optical Communication Division |
|       kirk@hpoclpa.hp.com          |                                |
|    Kirk Lindstrom / HP0100/UX      | 370 W. Trimble Rd.             |
| ph 408 435 6404 | fax 408 435 6286 | San Jose, CA  95131-1096       |
+---------------------------------------------------------------------+
From: "herb chong" <herb.chong@channel1.com>
Newsgroups: rec.audio
Subject: technics vs denon
Date: 18 Dec 92 04:59:54 EST
Reply-To: "herb chong" <herb.chong@channel1.com>
Distribution: rec
Organization: Channel 1 Communications

PS>Is this maybe a cultural difference?  I never thought I'd see the word
PS>'Marantz' and 'high-end' used in the same sentence.

many years ago, Marantz and high end were synonymous. a LONG time ago.

Herb...

---
  WinQwk 2.0 a#314  if(ThisDay()!=MyDay)DosSleep(ulTillNextDay);
--
Channel 1 (R)   Cambridge, MA

From: kirk@hpcc01.corp.hp.com (Kirk Lindstrom)
Date: Mon, 14 Dec 1992 19:30:51 GMT
Subject: Re: >Why do people buy speakers that cost >$1000/pair ?
Organization: Shredding the water of SF Bay, HP-OCD
Newsgroups: rec.audio

>|>    [...]                                   But the bottom line I 
>|> think is:  if you don't hear the difference and you are the only
>|> user, save the money.  I *can* hear the difference between speaker
>|> of 100 - 1000 - 10000 dollars, but I *can't* hear differences in
>|> speaker cables or interconnects, therefore, I bought the best speakers
>|> I can afford, but I'm using cables which give reliable contacts, but that
>|> are not "audiophile" cables.
>
>Suppose for a moment that there are differences, and that you can
>*learn* to hear them.  In that case, should you learn, and then need to
>buy better cables, or not learn, and save money?
>
>--brian

In all fairness, I haven't said much one way or the other.  I am now
listening to several different speaker and interconnect cables and would
like to ask:  "How do I learn to distinguish cables?"  All I listen to is
image, crispness of bass, decay of cymbals and triangles, how well a
very high note sounds while a deep low now it in the background.  What else
should I be listening to?  At times, some of the "better" cables sound a
bit more "open" or the notes a bit clearer, but I'm not convinced it is not
psycoacoustic since it doesn't happen all the time.  It will take a pretty
convincing demonstration for me to buy some of these $200-$500 wires where
well shielded, solid contact ones sound pretty good for only $50 and I can
make them for half that.

Kirk (enquiring, open ears want to hear) out
=> "We are what we pretend to be."  -  Kurt Vonnegut Jr.
+---------------------------------------------------------------------+
| Kirk Lindstrom - OCD Product R & D | Hewlett-Packard Co.  M/S: 91UA |
|   Engineer/Scientist, Hardware     |                                |
|------------------------------------| Optical Communication Division |
|       kirk@hpoclpa.hp.com          |                                |
|    Kirk Lindstrom / HP0100/UX      | 370 W. Trimble Rd.             |
| ph 408 435 6404 | fax 408 435 6286 | San Jose, CA  95131-1096       |
+---------------------------------------------------------------------+
From: henry@ginger.sri.com (Henry A. Pasternack)
Newsgroups: rec.audio
Subject: Re: Sovtek tubes.
Date: 16 Dec 92 03:27:49 GMT
Reply-To: henry@ginger.sri.com (Henry A. Pasternack)
Organization: SRI International


   This discussion has mostly centered on musical instrument amps.  I
have a slightly different question.

   Earlier in the year, I started building an amplifier based on an
article in "Glass Audio."  The amplifier used a pair of 6550's in
pentode mode driving some 5400 Ohm McIntosh replica output transformers
with a plate supply voltage of 620VDC.  It turns out that this is a
pretty rotten idea because a) the output transformers are really
only good for about 35W, b) 620VDC is a hell of a lot of B+ for a
6550, and c) the specified power transformers 1000VCT produce about
700VDC under load in a capacitor-input filter circuit.

   So, I have these output and power transformers and I'm trying
to figure out what to do.  If I hang a choke on the output of the
rectifier, I get a choke-input filter and a very stiff 450VDC.
(Despite protestations to the contrary, my research shows that
choke-input filters have some real advantages.  In fact, in the
old days, capacitor-input filters were considered to be distinctly
second-rate.  Part of the problem was due to poor peak current
capacity of vacuum diodes, rendering large capacitor-input
filters impractical.  What seems to be poorly appreciated these
days is that low-resistance silicon diodes in full-wave, center-
tapped circuits driving large capacitor-input filters put a
tremendous strain on plate transformers designed for vacuum diode
service.  Informed comments appreciated.  Flamers, take a leap.)

   Anyway, I was toying with the idea of building a ~30W amplifier
using two pair of 6L6GC's per channel in triode mode.  Alternatives
include the EL34 and the KT66.  I prefer triode mode because I
don't need a screen supply, and I get to hear for myself the triode
mystique sound.  I like the 6L6's and the KT66's because my data
books show low filament current, and I only have one 6A filament
winding.  All three of these tubes seem to have been designed with
triode mode in mind.

   I'd appreciate comments on this project idea.  Questions include:

   1) Is the effective 10,800 Ohm load per tube reasonable?
   2) Do I lose a lot of bandwidth compared to pentode mode?
   3) Are the Sovtek 5881/6L6WGC's advertised by New Sensor
      any good for hi-fi applications?
   4) What is the "Russian KT66" sold by VTL?

   Thanks.

-Henry
   
Newsgroups: rec.audio
From: droberts@aquila.astro.uiuc.edu (Doug Roberts)
Subject: Any comments on Rotel separates?
Organization: University of Illinois at Urbana
Date: Fri, 18 Dec 1992 20:09:37 GMT


A friend of mine is thinking about a Rotel Amp/Preamp combination.
Does anyone have any experience with Rotel separates or suggestions
for better quality/features in the same price range?  Thanks in
advance.  E-mail responses appreciated.

Doug Roberts
droberts@sirius.astro.uiuc.edu
Newsgroups: rec.audio
From: ichong@oracle.com (Ivan Chong)
Subject: Suggestions for Satellite Subwoofer speaker systems
Organization: Oracle Corporation, Redwood Shores, CA
Distribution: rec.audio
Date: Tue, 15 Dec 1992 20:16:11 GMT
X-Disclaimer: This message was written by an unauthenticated user
              at Oracle Corporation.  The opinions expressed are those
              of the user and not necessarily those of Oracle.


I'm interested in buying a subwoofer-satellite speaker system
in the $400 - $700 price range.  I will be using them for 
the front speakers in a surround sound setup.

I've listened to the Polk Audio RM 3000 system and was quite
impressed with the clarity and imaging capabilities.  The
"Good Guys" said they'd sell it to me for $679 + TAX.  They
also told me that they had open stock (recently returned items
still in box) for this model and would sell those to me for
$543 + TAX.

Does anybody know of a place where I can get them for less?

Any comments on these speakers from others who have had a chance
to listen to them?

I've also listened to the Boston Sub Sat Six system.  They also
sound pretty good, but not quite as clear as the Polk system.
Comments?

Any responses would be greatly appreciated.
-Ivan
ichong@oracle.com
From: lstowell@pyrnova.mis.pyramid.com (Lon Stowell)
Newsgroups: rec.audio
Subject: Re: Mobile Fidelity....
Date: 11 Dec 92 18:44:53 GMT
Reply-To: lstowell@pyrnova.pyramid.com (Lon Stowell)
Organization: Pyramid Technology Corp., Mountain View, CA

In article <1992Dec10.165018.29121@cypress.com> ssr@siberia.cypress.com (Bapcha/FPGA) writes:
>
>Has anyone bought these $29 CD's made by Mobile Fidelity ?  

    Guilty.  

>Are they
>significantly superior to the $12 CD's that you get from the neighbourhood
>CD store ?
>
   Well, they DO look cool, and that cute little finger that pops
   the CD out of the jewel box looks cool.  Audio
   quality....wellllll....maybe.  If you have a specific recording
   in mind, post it as some of the "remasterings" IMHO were wasted
   effort.  

   Whether the Dark Side of the Moon is worth the extra bucks is a
   fairly personal judgement.  I would say that there is not the
   profound differences there were between the MF vinyls and the
   original LP's.
From: mani@aix.Berkeley.EDU (Mani Varadarajan)
Newsgroups: rec.audio
Subject: Re: analog pride
Date: 18 Dec 92 16:10:26
Organization: University of California, Berkeley
Reply-To: mani@sprite.Berkeley.EDU
NNTP-Posting-Host: aix.berkeley.edu
In-reply-to: znpt01@trc.amoco.com's message of Fri, 18 Dec 1992 16:22:48 GMT

In article <1992Dec18.102248@trc.amoco.com> znpt01@trc.amoco.com (Norman P. Tracy) writes:
   > what puzzled me was the proud statement that ``This album was recorded,
   > mixed, and edited using analogue tape and sequential circuits technology.''
   > (the CD master was done through the sonic solutions system.)
   > 
   > 	is this some kind of perverse pride in doing things the hard way?
   > or were they trying, at least for LP buyers, to give people the opportunity
   > to get a pure analog processing path? and what can this mean for synthesised music?
   >

   It's a fact that many recording industry engineers/producers/artists still
   prefer analog recorders over digital.  (Please don't flame me for this statement,
   I'm just reporting what I've read.)

I heard Ray Dolby speak at a banquet recently, and he 
firmly believes that analog is better for recording live
music, since there can be unexpected spikes in the music
that digital can't pick up but analog can.  I think he said
it had something to do with the dynamic range or something
like that.

He also said that he does like to listen to CDs, so he's 
not *firmly* anti-digital or anything.

Peace,
Mani

Newsgroups: rec.audio
From: brambo@eco.twg.com (Mark Bramblett)
Subject: Re: Opinion on M&K sub
Followup-To: rec.audio
Organization: The Wollongong Group (East Coast Operations)
Date: Tue, 15 Dec 92 21:39:16 GMT

In article <1992Dec15.163700.7465@bmerh85.bnr.ca>, stud1b53@bnr.ca (Anshu
Prasad) wrote:
> 
> In article <0f=BXAq00Uh7M400xu@andrew.cmu.edu>, Bambang Suryanto <bs3f+@andrew.cmu.edu> writes:
> |> Anybody has comment on M&K sub espessially the MX-70? Good or bad?
> |> Anyone ever try to connect it with DR-7?
> |>
> 
>   I think M&K subs are fantastic.  For the money I think they sound
> (and feel) much better than comparably priced Velodynes.  The MX-70 is
> the one I've tentatively picked to go with the Def Tech BP-10's (in
> a home theater application).  I'm going to have to audition it in my 
> sound room before I make the final decision.  I think the MX-70's dual
> 8" drivers in push-pull configuration outperform even M&K's 12" single
> driver systems.  It should sound just as good with the DR-7's (which are
> pretty much the unipolar equivalents of the BP-10's).
> 

I have a follow-on question to use of the MK subwoofer and Definitives.
I just purchased 4 BP-20s and 2 C-1's to go into a surround sound
arrangment
and I have more bass than I can deal with (...grin!).  Do you really feel
you need a subwoofer as well?


Mark Bramblett

VMS Program Mgr
The Wollongong Group

brambo@eco.twg.com
From: desmondw@merrimack.edu
Newsgroups: rec.audio
Subject: Separates vs. AV Reciever
Date: 11 Dec 92 17:21:12 GMT
Organization: Merrimack College, No. Andover, MA, USA

Hi, I'm looking for some opinions on going the separates route vs.
an A/V Reciever. It would have to be versatile(I watch movies in
Pro-Logic and listen to the radio). Right now I have a technics
reciever(SA-GX710) and a pair of Boston Acoustics t-930's floor
speakers and a Boston Acoustics 525v center channel. I wouldn't
want to change the speakers, only upgrade the source. Would simply
adding the Yamaha DSP1000A do the job?
Newsgroups: rec.audio

>I have a pioneer vsx-4900s receiver and cerwin vega dx-7 speakers.  
>Now the problem is that cerwin vega is rated at 4 ohms and the pioneer
>receiver is to be used at 8 ohms.  I fear that hooking up these would
>result in some damage to the receiver.  How can I fix this problem? 
>Should I use my advents to hook up to my receiver along with cerwin
>vegas?  Any suggestions would be appreciated.  

What you need is a 2:1 impedance transformer. Rather than spending big
bucks for one of these, you can make one yourself. Take a cylindrical
object such as an empty toilet paper roll or a pencil and wrap some wire
around it. Take a piece of wire with two turns and connect it to the 8
Ohm receiver. Use another piece of wire with one turn and connect it to
the 4 Ohm speaker. Use some quality cement such as Elmer's to keep the
wires from coming unwound. Viola!

;-)

Allan
Newsgroups: rec.audio
From: slr3e@Virginia.EDU ("Stacy Lee Roach")
Subject: Re: Speaker Advice
Organization: University of Virginia
Date: Tue, 15 Dec 1992 18:43:08 GMT

mlm2@crux1.cit.cornell.edu  writes:
> Anyone have any opinions on the Infinity SM112, Infinity Reference 5, 
> Infinity Reference 6, EPI 120-III, Advent Heritage, or Advent Laureate
> speakers? I am looking for a new pair of speakers and I have seen these
> and I wonder what people think/know about them.

I have listened to all the Reference series extensively and I
am impressed with all of them, however if you would like
something with a little tighter base and what I feel to be more
accurate look into the NHT's 1.8.  They can handle up to two
hundred watts, +-3db 43-20k, and sound amazing.  They cost
about $700 and are well worth every penny.
					slr3e.virginia.edu
From: d0neon@dtek.chalmers.se (Mathias Kremer)
Newsgroups: rec.audio
Subject: Ticking CD-player
Date: 16 Dec 92 12:00:47 GMT
Organization: Chalmers University of Technology, Gothenburg Sweden


	I recently bought a new Technics SL-PG520A CD-player.
	It produces an irritating ticking sound when playing
	discs (i.e. not only when loading or searching).
	I am very disappointed with this, and would like to
	know if anybody else has experienced the same 
	problems. Is there any way of fixing them?
	The shop where I bought the machine says the sounds
	are normal and that I was unlucky getting a player
	that sounds louder than the average one.

	
Newsgroups: rec.audio
From: fineberg@wilbur.nas.nasa.gov (Samuel A. Fineberg)
Subject: Re: I just tested DCC and MD...
Organization: CSC, NASA Ames Research Center, NAS Division
Date: Tue, 15 Dec 92 23:12:57 GMT
Reply-To: fineberg@nas.nasa.gov

In article <1992Dec15.131210.22544@wuecl.wustl.edu>, amc@wucs1.wustl.edu (Adam Costello) writes:
|> In article <Bz4t27.Dp@watserv1.uwaterloo.ca> bmaraldo@watserv1.uwaterloo.ca (Commander Brett Maraldo) writes:
|> >
|> 
|> >ps.  Incedentally, DAT prices (for media and machines) are cheaper than for
|> >DCC and MD.
|> 
|> Really?  MD recorders are being introduced at $700.  Where can I get
|> a DAT recorder for that price?
J&R Music world, Fry's, the good guys, any other place that sell's the Sony home
deck. (actually I think they are only $600)

Sam
Newsgroups: rec.audio
From: dsk@ravl.rice.edu (Dan S. Kirkpatrick)
Subject: Building headphones
Organization: Rice University
Date: Tue, 15 Dec 1992 22:48:02 GMT

I am embarking on a project to build a pair of electrostatic headphones.
I was wondering if anyone out here has had any experience building
headphones.  Any ideas on how to construct the headphone assemblies?
I've checked into prices on Stax headphone assemblies, and they run int
the $250+ range for the type I want, which almost defeats the purpose of
building them myself.  

Thanks.

-Dan

-- 
"I do not want to be immortalized through my works; I want to be 
immortalized through not dying."  -Woody Allen

Dan Kirkpatrick                 | Dept of Electrical & Computer Engineering
~dsk@rice.edu                   | Rice University
uunet!rice.edu!dsk@uunet.uu.net | Houston, TX
From: "herb chong" <herb.chong@channel1.com>
Newsgroups: rec.audio
Subject: mobile fidelity....
Date: 18 Dec 92 04:59:54 EST
Reply-To: "herb chong" <herb.chong@channel1.com>
Distribution: rec
Organization: Channel 1 Communications

BA=>Has anyone bought these $29 CD's made by Mobile Fidelity ?  Are they
  =>significantly superior to the $12 CD's that you get from the neighbourhood
  =>CD store ?

define significantly. i have 7. they sound very good, but better? i
think different is the better adjective. i have four copies of Pink
Floyd's Dark Side of the Moon:  regular MFSL record, UHQR, Harvest CD,
and UDCD. they all sound different. the difference in the CD's reflect
the different choices in EQ made at mastering time. the UHQR and UDCD
sound different too, but once again, it is a matter of who did the
mastering.  Except for my Sting UDCD, i have either the record or CD
version of the rest. the UDCD is slightly clearer in sound in all cases,
but that could simply because of less roll off in the high end and
nothing to do with the CD itself. the Sting CD is the only UDCD
i have which comes from a digital master. the rest are from analog
masters.

Herb...
---
  OLX 2.2  WOBBLEWOBBLEWOBBLEWOBBLE THUNK THUD BANGBANGBANG >CRASH<
--
Channel 1 (R)   Cambridge, MA

Newsgroups: rec.audio
From: ab@nova.cc.purdue.edu (Allen B)
Subject: Re: Digital-to-Digital copying
Organization: Purdue University
Date: Fri, 18 Dec 1992 18:09:39 GMT

In article <1992Dec15.203255.19866@nntpd2.cxo.dec.com>  
winalski@adserv.enet.dec.com (Paul S. Winalski) writes:
> 
> In article <Bz9rCs.J7t@ssesco.com>, nau@ssesco.com (William Nau) writes:
> |>As long as I'm at it.  Suppose I feed the digital signal into my home
> |>PC.  Is it illegal for me to clear those bits in my PC? 
> if your intent in using the PC
> to clear bits is to circumvent SCMS in a device setup that is considered
> consumer digital audio by the AHRA's definition, then yes, it's technically
> illegal.

It may also be illegal to store the music in your PC.  I don't
know how binding those things are, but nearly every book
has one- I doubt music would be any different.

"No part of this publication may be... stored in a
retrieval system...."? 

ab
Newsgroups: rec.audio
From: bill@verdix.com (William Spencer)
Subject: Re: tweaks for cheap speakers
Organization: Verdix Corp
Date: Tue, 15 Dec 1992 22:55:30 GMT

>>Mark "Pi" writes:
>>|> I wanted better bass response out of my el-cheapo Yamaha speakers 
>>|> (model NS-4), so I pushed them back against the wall. (They had been
>>|> sitting out about 8-10 inches from >|> it.)  Voila!  More bass.
>>|>
>>|> Now, however, I'm really noticing how "mushy" the bass is.  Was the
>>|> bass always this mushy, and I just didn't notice it before?  Or is this
>>|> another effect of the speakers being closer to the wall?  And most
>>|> importantly, is there anything I can do to "tighten" up the bass, without
>>|> losing too much of the response, that will cost very little?  (If I had 
>>|> money I'd just buy some better speakers.)

It could be that you're hearing how imperfect it is, but there's a few other
things. Does the wall resonate? THe distance from the wall will cause 
cancellations, along with the distance to the floor and other surfaces. The
effects could be combining -- try a different height. The distance from
each wall/surface will be equal to a quarter wavelength at the frequency of
cancellation. For an 8" distance, that's about 350 Hz. THere is also a peak 
at the half wavelength, 175 Hz, dip at 3/4, peak at one wavelength, etc.
The dips alone can exaggerate the peaks of the speakers themselves at other
frequencies.

You might try putting foam or other absorbent on the wall behind the speaker.
It won't do anything a the deeper frequencies but it will do a lot at 350 Hz.
Believe it or not, the absorbent effect will actually make the sound louder at
this frequency.

DPierce@world.std.com (Richard D Pierce) writes:
>In article <1992Dec14.184317.17716@bmerh85.bnr.ca> shiv@bnr.ca (Shiv Naimpally) writes:
>>Get an equalizer. Pick up an eq with 10-12 bands per side. You should be

>It's a common myth that an equalizer is useful in this application. The

Yeah, but getting rid of a lot of bass over a wide range would certainly deal
with the problem :). One concern you didn't mention: distortion. If distortion 
is causing the muddiness, leave the speakers against the wall and cut bass
to reduce distortion (tone controls should do it).

Bill s