HDTenEightyP/NetNews huggingface dataset:
From: chowkwan@alumni.cco.caltech.edu (Raymond Maihin Chowkwanyun)
Newsgroups: rec.audio.high-end
Subject: When is a db not a db?
Date: Tue, 15 Dec 92 12:16:19 PST
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu


I've heard it said that a watt of tube power sounds louder than
a watt of transistor power.  In fact, I can attest to hearing
this phenonmenon.  Is it possible then that a db from an
omnidirectional speaker sounds louder than a db from a direct
radiating speaker?

Issue 83/84 of absolute sound has a rave review of the mbl 101,
dubbed the Teutonic Tangerine by the British Press.  Though
I think it looks more like a pineapple.
On Page 138, the reviewer, Gindi, raises the issue of
the 81db sensitivity rating of
the 101 with the speaker's designer, Jurgen Reis.  Reis dismissed
the conventional 1 watt, 1 meter measurement as irrelevant to
omnidirectional speakers such as the 101, citing its greater
radiating area as compared with a conventional direct radiating
driver.

As I understand Herr Reis, he's saying that sticking a mike 1
meter on axis fails to capture a lot of the energy that 
an omni, ipso facto, is spraying out in all directions.
So it would be interesting if mbl would take sensitivity
measurements at a point further out in the room that would
correspond more closely with a real world listening position
and compare that with a few well-known direct radiators.

I'd be interested to hear from any Shahinian Diapason owners.
Does an omni indeed sound louder than it measures?

-- ray
From: mikero@microsoft.com (Michael Robin)
Newsgroups: rec.audio.high-end
Subject: Re: Linaeum Speakers
Date: 15 Dec 92 22:25:36 GMT
Organization: Microsoft Corporation
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

>I'd appreciate hearing some additional opinions about these
>speakers.  Thanks in advance.
>Fred

I didn't think they were especially exciting in any aspect (many
people regard this as a good thing). One thing to remember is,
by virture of the design, that the vertical swwet spot is very narrow -
i.e, stand up and the highs disappear. (Kind of like the Stages.)
I also seem to recall hearing some breakup at higher listening levels.
Nice and open, though. Give them a listen and see if you like them. 

m

ps- anybody listen to the BA lynfields yet?
From: zzjim@stein.u.washington.edu (Zeming Gao)
Newsgroups: rec.audio.high-end
Subject: Rotel 855 CD player for sale
Date: Thu, 17 Dec 1992 20:24:35 GMT
Organization: University of Washington, Seattle
Distribution: seattle
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu


I use the ROTEL 855 CD player mostly for headphone listening 
through the headphone output of a Sherwood receiver, both because 
i don't want to be bothered and my speakers are not great ones. 
(The Rotel DOESN'T have a headphone out!). The ridiculous 
setting was from my naive idea to get a high-end sound without 
being burned out. When my old amp(bought cheap used) broke down, 
i bought that Sherwood receiver, thinking that i mostly use 
headphones anyway, why push myself so hard to buy expensive amps? 
But i recently realized that i am not getting the real sound 
from the Rotel through the Sherwood's headphone jack either
(to be honest, i didn't even know a headphone out is in principle 
a little amp and therefore  has the issue of PERFORMANCE). 
Now I either upgrade my system around the Rotel, OR, let the Rotel
go and get a reasonable CD player which has a good headphone out, 
better than Sherwood's of course. I've decided NOT to go the 
former. Have to resist it!

 Ask $270 or best offer. Bought around August 1991. 
Still under 5 year Warranty. With the original package.

  Also, i would appreciate any suggestions on CD players under
$300. Remember i use the headphone output very often.

Thanks!
From: peterca@ento.csiro.au
Newsgroups: rec.audio.high-end
Subject: Re: Re: Re:Re: twin triode crosstalk question
Date: Thu, 17 Dec 92 11:25:38 EST
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu


>Excuse me, folks, but you need to get your hands on a tube manual and stop
>speculating!
I wish I could.  I'm trying.  Does anyone want to sell me one?

I originally wrote:  "I'm not sure if that is correct but it sounded
plausible."
>
>Not correct, and not plausable because of the design. (then the explanation why)
Thank you and its good to get logical and informed answers.  I like this
newsgroup.

>DC is used to further reduce hum over a balanced AC supply, and not to extend
>life.  The heater is center-tapped to allow flexibility in heater voltage
>choice and the parallel connection usually provides lower hum. Running one
>half of the heater will not heat the cathode to its proper emitting
>temperature!
>

>|> The filament is center tapped so you can run each half from 6V in parallel
>|> or 12V in series, or only one half.  
>
>Wrong -- see above!
>
>|> I would expect that with only one half producing heat at
>|> any particular time the pair of triodes would have increased life.  
>
>It would last forever, but there wouldn't be any free electrons to put to
>work!

This is where my experience is in conflict with the theory.  I have a valve
preamp made locally.  It uses a shunt regulated push pull circuit which is
virtually identical to another design I use.  The one difference is that
for some reason I can't fathom it uses one half of each of two 12AX7s for
each channel with a 6V supply on one half of the filament.  It just seems a
waste to me but it works just fine.  I'd love to know why the designer
(Laurie Cohen) did this.  The supply voltage is roughly the same as the
design which uses the two halves of one 12AX7 and 12V on the whole filament
and the current through the two circuits are similar.  
Also I will soon post about what the amp is going to hopefuly be doing from
now on.  I have just changed the Cohen amp to run (less wastefully) on one
dual triode/channel, it now has 12AT7s and it is now about to do service as
the complete analogue stage for my CD player.  The prototype was very
promising.  

----------------------------------------
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: Scott Dorsey <kludge@grissom.larc.nasa.gov>
Newsgroups: rec.audio.high-end
Subject: MD
Date: Wed, 16 Dec 92 15:07:58 EST
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu


I heard the new Sony MD at a recent trade show, and was less than
impressed.  They claimed that they could get 75 min on a disc, although
all the blanks they showed were 60 minute ones, and none of their demo
discs were anywhere near that long.  With a simple demonstration with
a digital source, the difference between the original recording and
the playback was painfully obvious.  There were a lot of rather interesting
artifacts, which were even audible on the cheap Sony speakers they were
using for the demo.  It is possible that these differences could be the
result of differences between the A/D convertors on the CD player and
the MD unit (since the actual recording process was done with the digital
output from the CD, but the playback comparison was done from the
analogue outputs).  Still, I am not impressed by any means.

I have a couple of DCC machines on the test bench in the garage right 
now, and while they aren't up to the quality of 1/4" open-reel, the
artifacts aren't all that obvious; you at least have to listen for them.

In the meantime, I'm not getting rid of my DAT machine, thank you very
much.
--scott
From: mlm2@crux1.cit.cornell.edu (Mark Lee Margolis)
Newsgroups: rec.audio.high-end
Subject: Parasound HCA-1200 and HCA-2200 amps
Date: 18 Dec 92 04:08:26 GMT
Organization: Cornell Information Technologies
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

Anyone have any experience with the above mentioned amps? I am thinking 
about upgrading from the Parasound HCA-800II in order to get more power
(I like my music loud and I always have these nervous feelings about 
clipping). Anyhow, how do the above two compare to the HCA-800II and
to each other. Also, how do they compare to other high end amps?

- Mark

--
**********************************
Mark L. Margolis
mlm2@crux1.cit.cornell.edu
fnox@vax5.cit.cornell.edu
From: schludermann@sscvx1.ssc.gov
Newsgroups: rec.audio.high-end
Subject: RFI:New DYNACO electronics
Date: Wed, 16 Dec 1992 16:38:36 GMT
Organization: Superconducting Super Collider Laboratory
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

I have an old dyanco QSA-300 quad amp (essentially to st-150 on one chassis)
The electronics are getting noisy. I seem to recall a company that sold
upgrade electronics for dyanacos. I'd also appreciate ideas on power supply
mods.

kris
From: KLUDGE@AGCB1.LARC.NASA.GOV
Newsgroups: rec.audio.high-end
Subject: A/V sound
Date: Tue, 15 Dec 1992 10:32:19 -0500 (EST)
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

So far most of the A/V receivers I have heard are pretty dreadful, but
that's not surprising, since they don't have to be good.  VHS standard
video is in the AM radio quality range (although I know of one AM radio
engineer that would be offended by the comparison), although the VHS HI-FI
system (where the sound is carried on a video subcarrier instead of a linear
track), is almost acceptable, maybe into the FM or 16mm film range.

And NTSC video is absolute garbage, but I've told you that already.

Your best bet if you want to get a surround system set up is to buy an
outboard surround decoder and use your existing equipment.  Make sure
the decoder has at least a reasonable quality delay line (most of them
have absolutely horrible bucket brigade systems, although some of the
better ones like the Shure have digital lines).  

Avoid the HX-Pro systems... they are easier to set up but they have some
problems with imaging to say the least (and you can read my article in
Positive Feedback if you want more information).
--scott
From: Scott Dorsey <kludge@grissom.larc.nasa.gov>
Newsgroups: rec.audio.high-end
Subject: Carmina Burana
Date: Wed, 16 Dec 92 15:13:33 EST
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu


The best recording of Carmina Burana is the Telarc Recording with the
Atlanta Symphony.  I'm not just saying this because I sat in on the
recording session; I'd say it anyway because it's a good sounding
recording.  The dynamics are nice and clean, the voices are realistic,
and the performance is nothing short of spectacular.  Try to ignore
the bass imaging problems (which you probably wouldn't have noticed
anyway if I hadn't mentioned them).
--scott
From: chowkwan@alumni.cco.caltech.edu (Raymond Maihin Chowkwanyun)
Newsgroups: rec.audio.high-end
Subject: Guidance for beginners
Date: Tue, 15 Dec 92 12:42:22 PST
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu


Someone was asking for guidance in putting together his
first high end system.  It would help if this person
had specified a budget, room size, musical preferences,
listening biases.

Issue 83/84 of absolute sound has some of the reviewers
going thru the exercise of putting together systems
at the $2.5K, $5K, $15K, and cost no limit levels.
The usual rules apply about listening for yourself, preferably
with the gear in your own room.

Oftentimes the reviewers would go over-budget.  Let that
be a warning to you all.  It takes an iron will to pass up
that component that sounds just a bit better for a bit
more money.  Therefore, I would suggest considering 
buying used gear from Audiomart.  For $25 you get 12 subscriptions
filled with about 300 ads for audio gear of all price ranges.
Their address is Route 3, Box 692, Crewe, VA 23930.
Rule of thumb is to expect used electronics to go for 60%
of list and used wires for 50%.  Of course, buying used makes
the advice about home auditioning hard to follow.  
Each individual has to work out that conundrum for himself.

One other thing: Audiomart is also a place where you can
try to sell your gear if you decide you made a mistake.

-- ray
From: bilver!bill@peora.sdc.ccur.com (Bill Vermillion)
Newsgroups: rec.audio.high-end
Subject: Re: Amplifier specifications
Date: Wed, 16 Dec 1992 15:39:20 GMT
Organization: W. J. Vermillion - Winter Park, FL
  (5.67a/IDA-1.5 for uunet!rec-audio-high-end); Wed, 16 Dec 1992 14:24:46 -0500
	id <m0n24Oe-0001RPC@tous.oau.org>; Wed, 16 Dec 92 14:27 EST
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

In article <1g7j10INN1fm@uwm.edu> gfl@herahera.cc.bellcore.com (lenahan,grant f) writes:
>In article <1g569nINNjeo@uwm.edu>, bhoughto@sedona.intel.com (Blair P. Houghton) writes:
>> I'm sorry.  4.4 V/us is sufficient for 25MHz; for 25kHz
>> you only need 4.4 mv/us...

>No, you were right before.  25 kHz, not 25 Hz, remember.

>Anything under 20 V/uS for power amps is terrible.

>4.4 v/uS is fine for a preamp, since 2.2 V rms is typical
>maximum Vout.

As a point of reference, in the ES line, Sony's N77 (since
replaced by the N80) show 300v/usec in the low level sections
and 150v/usec in the output stages of their power amps.

Rated at 200w/ch.


-- 
Bill Vermillion - bill@bilver.oau.org  bill@bilver.uucp
                - ..!{peora|tous|tarpit}!bilver!bill
From: chcho@vnet.ibm.com ( Chul-hee Cho )
Newsgroups: rec.audio.high-end
Subject: Harbeth HL Compact
Date: Mon, 14 Dec 92 13:49:34 KST
Organization: IBM Korea
NNTP-Posting-Host: 129.89.7.4
News-Software: Usenet 3.0
Originator: tjk@csd4.csd.uwm.edu

I like to hear opinions on British speaker HL Compact which
is manufactured by Harbeth.  I like to know its strengths and
weakness compared with Spendor SP2/2, EPOS ES-14, and Snell Q.


Chul-hee Cho
IBM Korea                                      Voice : 82-2-781-6315
chcho@sulvm1.vnet.ibm.com                        Fax : 82-2-785-5948
From: malte@techfak.uni-bielefeld.de (Malte Uhl)
Newsgroups: rec.audio.high-end
Subject: Re: Amplifier specifications
Date: Mon, 14 Dec 1992 13:34:19 GMT
Organization: Universitaet Bielefeld, Technische Fakultaet.
	by mail.Germany.EU.net with SMTP (5.65c/EUnetD-2.2.1.c)
	via EUnet for uunet.uu.net
	id MS23280; Mon, 14 Dec 1992 14:30:01 +0100
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

In article <1g7j10INN1fm@uwm.edu>, gfl@herahera.cc.bellcore.com (lenahan,grant f) writes:
|> Anything under 20 V/uS for power amps is terrible.
|> 
|> 4.4 v/uS is fine for a preamp, since 2.2 V rms is typical
|> maximum Vout.
|> 
|> Grant

How comes that slew rate < 20 V/sec is terrible ? My NAD 2155, rated at
55 W(RMS) is specified to have a slew rate of 5.5 V/sec. It doesn't
sound terrible at all!
You''l also rarely find a tube amp with that slew rate.

Malte
From: AA10000 Wally Knapp  Computer Services  x4461 H239 <AA10%CATCC.BITNET@VTVM2.CC.VT.EDU>
Newsgroups: rec.audio.high-end
Subject: FOR SALE: Bozak Speakers
Date: Mon, 14 Dec 92 09:07:18 EST
Organization: University of Wisconsin - Milwaukee
   Mon, 14 Dec 92 09:01:34 EST
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

LAST CALL - 8 12" Bozak woofers
           16  4" Bozak tweeters
            2 10" Goodmans midranges
            2 3-way N10102 xovers
            2 12 cubic foot mahogany cabinets (B310's)

All in excellent condition.  $ 450. buys the lot but you must pick them
up in Baltimore, Md.  The perfect place for a holiday visit!  A great
opportunity for someone who wants to build smaller systems from these
excellent componets.  Bozak is still maintained by a company in New
England.  They go to the dump if I don't get a taker.

Send E-mail or telephone Day   410-455-4461
                         Even  410-461-4954

Regards,  Wally Knapp

+++----------------------------------------+++-----------------------+++
| Wallace C Knapp CSP Dir Computer Services |  BITNET    AA10000@CATCC |
| Catonsville Community College             |  Tele/Vmail 410-455-4460 |
| 800 S Rolling Road                        |                    -4461 |
| Baltimore Md  21228                       |  Building H   Room 239 A |
+++------- Community Colleges Serve 52% of Maryland Students!  ------+++
From: Travis Stansbury <travis@MINERVA.CIS.YALE.EDU>
Newsgroups: rec.audio.high-end
Subject: Mods to Adcom GTP-400?
Date: Wed, 16 Dec 1992 16:30:35 -0500 (EST)
Organization: University of Wisconsin - Milwaukee
NNTP-Posting-Host: 129.89.7.4
Mime-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Originator: tjk@csd4.csd.uwm.edu


I've got an Adcom GTP-400 that I would like to modify.  Here is what I had
in mind: building an ouboard power supply!  It seems that as a solid state
preamp, the power supply will only need to provide +- DC rails, which
would be easy to build as an outboard, regulated unit.  My questions are
these: where, and at how many places would the power need to be supplied
to?  Is there only one DC voltage used?  How difficult does this sound
(completely crazy?)?  AND can I get schematics/circuit layouts from Adcom
or other suppliers?  Thanks, and if anyone has mod'ed any Adcom preamps,
please email me.  

   ______________________________________________________
   | Travis Stansbury, Yale '94  || 2358 Yale Station   |
   | travis@minerva.cis.yale.edu || New Haven, CT 06520 |
   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
From: lipp@mtu.edu (JOHN I LIPP)
Newsgroups: rec.audio.high-end
Subject: Re: When is a db not a db?
Date: Wed, 16 Dec 1992 17:22:16 GMT
Organization: Michigan Technological University
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

>I've heard it said that a watt of tube power sounds louder than
>a watt of transistor power.  In fact, I can attest to hearing
>this phenonmenon.  Is it possible then that a db from an
>omnidirectional speaker sounds louder than a db from a direct
>radiating speaker?

I believe a more correct statement is that a watt from a class A amp sounds
louder than a watt from a class AB amplifier (many tube amplifiers are class A
designs).  Class AB designs are often compromise designs (you trade power
consumption for better efficiency and other things).  Also, most transistor
amplifiers are designed using several constant current sources which don't give
the amplifier a great deal of headroom.

>As I understand Herr Reis, he's saying that sticking a mike 1
>meter on axis fails to capture a lot of the energy that 
>an omni, ipso facto, is spraying out in all directions.
>So it would be interesting if mbl would take sensitivity
>measurements at a point further out in the room that would
>correspond more closely with a real world listening position
>and compare that with a few well-known direct radiators.

The SPL efficiency rating will be less for an omnidirectional speaker than for
conventionally designed speakers.  However, the difference is not that great.  A
conventional speaker radiates into what is considered a hemi-spherical
environment (since tradationally placed against or near a wall).  An omni-speaker
is radiating into a sphere; the result is double the energy density for a
conventional speaker and a corresponding increase of 3 dB in effeciency over an
equivalent omni design (or you could look at it as an omni is 3 dB less
efficient).

The SPL level you will perceive is made up of two factors: (1) the sound that
directly radiates from the speaker and (2) the sound that has reflected off the
walls, but has arrived in time for you to be unable to immediately differentiate
it from the direct sound (as opposed to reflections that arrive so long after the
initial wave that they sound like reverberation or "echoes").  I would suspect
then that the closer the omni is to a wall (and/or floor/ceiling), the louder
it will sound because more energy will be bounced backed to listeners.

Also keep in mind how SPL measurements are made.  Some measurement techniques
"gate" the incoming sound so that only the direct wave is measured.  Any
reflections are consequently rejected, even though they may be an important part
of the sound spectrum and SPL.

Hope this helps.

/***************************************************************************\
*  John Lipp   *  Loudspeaker design pseudo-expert and software developer   *
* lipp@mtu.edu * (Working on amplifier and surround-sound psuedo-expertise) *
\***************************************************************************/
From: fingersh@ucsu.Colorado.EDU (FINGERSH  LEE JAY   )
Newsgroups: rec.audio.high-end
Subject: Connectors
Date: Tue, 15 Dec 1992 23:47:25 GMT
Organization: University of Colorado, Boulder
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

Hi.  I have a question that I have not often seen discussed in this group.
I have my speakers bi-wired with Monster Cable on the bottoms and Kimber
wire on the tops.  The Monster Cable has pins for connectors and the
Kimber wire is bare on both ends.  I tighten down the studs on the speakers
and the connectors on the amp as tight as I can.  Are these end connections
as solid as they could be?  What type of connectors give the best sound?
 
I chose to leave the Kimber wire bare because I thought that would be the
most solid connection I could get.  I chose pins on the Monster cable
because they fit into the amp.
 
Comments would be appreciated.
 
Lee Jay Fingersh
From: mzk20@spa.amdahl.com (Makoto Kobayashi)
Newsgroups: rec.audio.high-end
Subject: Western Electric Models 42, 43, and 87
Date: 16 Dec 92 17:45:52 GMT
Organization: Amdahl Corporation  Sunnyvale, CA
  (5.65c/IDA-1.4.4 for <rec-audio-high-end@ames.arc.nasa.gov>); Wed, 16 Dec 1992 09:45:44 -0800
	id <m0n22oM-00004sC@amdahl.com>; Wed, 16 Dec 92 09:45 PST
	id <m0n22oM-00003GC@amdahl.uts.amdahl.com>; Wed, 16 Dec 92 09:45 PST
	id <m0n22oi-0000eKC@juts.ccc.amdahl.com>; Wed, 16 Dec 92 09:45 PST
NNTP-Posting-Host: 129.89.7.4
Keywords: power amp
Originator: tjk@csd4.csd.uwm.edu


I am looking for the parts, particularly the input and the output
transformers, used in the Western Electric Models 42, 43, and 87
power amplifiers.  These models were supposedly developed in the
1930's.  I am planning to build a pair of power amplifiers to
drive a pair of Quad ESL 63 Pros.  My question is where I can get
them.  Any ideas?  I will also appreciate any suggestions on the
substitute transformers.
From: kensib@rpi.edu (Brian C. Kensing)
Newsgroups: rec.audio.high-end
Subject: Buying Home Audio Components?
Date: Mon, 14 Dec 1992 18:39:23 GMT
Organization: Rensselaer Polytechnic Institute, Troy, NY.
Reply-To: kensib@rpi.edu
NNTP-Posting-Host: 129.89.7.4
Originator: tjk@csd4.csd.uwm.edu

[This is the kind of question where you write a long answer 
 and post it to the newsgroup. -tjk]

I am looking to buy high-end home audio equipment for the first
time.  For the past four years I have been involved in the
installation of car audio equipment and have a wealth of
knowledge on the various components, but seem to find myself a
bit confused when it comes to home audio.  Right now I am
looking for a pre-amp tuner, amp, and a set of speakers.  I
would appriciate any advice on what to look for in each of
these catagories.

					Thanks,
					   Brian C. Kensing
					   (kensib@its.rpi.edu)