Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

The Lounge A place to talk about almost anything but politics and religion.

Sound Quality Vs. Measurements
Sound Quality Vs. Measurements
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 3rd July 2013, 02:04 PM   #9651
nigel pearson is offline nigel pearson  United Kingdom
diyAudio Member
 
Join Date: Mar 2007
Location: Oxfordshire
Simple 40 Watt Power Amplifier

In another thread I was told off for calling a Douglas Self/Sinclair amp a modified HC Lin circuit . The amp above is approximately a Lin circuit . Looking at it I wonder if the original is rather good ? Having a bit of current to drive the VAS seems no bad thing . I wonder if like bootstrapping a good idea has been forgotten ? The bootstrap CCS to a VAS is not without virtue . Keep crossover distortion low , IM low and THD reasonable . Who knows ? DIN 45500 to 10 watts would be OK . I am sure that could be bettered . Lin was 2 % THD 6 watts circa 1957 ?

The 68 pF VAS cap could be split . Feed the output into the VAS double cap node . Who knows , the already reasonable 10 kHz performance might be asked to be good to 20 kHz ? The open loop gain is low . It doesn't mean it has to be a bad performer . It could even have feed forward correction . The Quad 405 is said to be both a feedback and feed forward amp . The feedback being rather important and seldom stressed .

Last edited by nigel pearson; 3rd July 2013 at 02:15 PM.
  Reply With Quote
Old 3rd July 2013, 02:19 PM   #9652
davidsrsb is offline davidsrsb  Malaysia
diyAudio Member
 
Join Date: Dec 2005
Location: Kuala Lumpur
Quote:
Originally Posted by fas42 View Post
The big picture is very simple: people enthusiastic about audio want playback to sound like the "real thing"...
Having spent hours in a room with real musicians rehearsing, you do not want the real thing at all.

The dynamic range of drums is way to high for domestic playback. Compression is essential
  Reply With Quote
Old 3rd July 2013, 02:47 PM   #9653
mr_push_pull is offline mr_push_pull  Europe
diyAudio Member
 
Join Date: Mar 2004
Location: At the output stage
Send a message via Yahoo to mr_push_pull
Quote:
Originally Posted by davidsrsb View Post
Having spent hours in a room with real musicians rehearsing, you do not want the real thing at all.

The dynamic range of drums is way to high for domestic playback. Compression is essential
as far as I'm concerned, this quest for the real thing is the biggest trap in audio. you just want music to sound pleasant.
did it occur to anyone that the studio crew involved in the production of that CD never intended it to sound like the real thing, and not because they couldn't?
__________________
we all love a good ol' stereotype until it's against us
  Reply With Quote
Old 3rd July 2013, 05:54 PM   #9654
hpeter is offline hpeter  Slovakia
diyAudio Member
 
hpeter's Avatar
 
Join Date: Feb 2013
Location: Electrostats or bust
Quote:
Originally Posted by nigel pearson View Post
How exciting . The only Roswell thing I heard that tickled my imagination was that the transistor came form it . The more interesting claim was we jumped 800 years by knowing it . We often enjoy science fiction . For once in our domain .

My research says we were on the way long before 1947 ( 1927 ) . The more sensational claim was Intel had stuff to copy .

A further claim is that Bell will not release the original samples of transistor as they were not germanium . They were slithers of chip . To fake some germanium is no big deal . Slithers of chip , really ?

I often debunk conspiracy theories . This was one .
...and laser. aaand godknowswhatelse
__________________
BLOG. XMOS_U8/PCM5102A > LL1544A > 6H9C+gyrator > 2A3_SOV/JJ > LL1660 > STAX SR207 _ SR L300 _ SR007 # LL2748 > 394A > LC 12H/1000
  Reply With Quote
Old 3rd July 2013, 06:05 PM   #9655
bcarso is offline bcarso  United States
diyAudio Member RIP
 
Join Date: May 2005
Location: Canoga Park, California
Yes that was one of the silliest theories I ever saw, as if we had known nothing about solid state physics before the saucer crash etc.

I hear they did have some nice cables though
  Reply With Quote
Old 3rd July 2013, 08:26 PM   #9656
rdf is offline rdf  Canada
diyAudio Member
 
rdf's Avatar
 
Join Date: Jun 2004
Location: big smoke
Quote:
Originally Posted by mr_push_pull View Post
as far as I'm concerned, this quest for the real thing is the biggest trap in audio. you just want music to sound pleasant.
did it occur to anyone that the studio crew involved in the production of that CD never intended it to sound like the real thing, and not because they couldn't?
Unprincipled relativistic utilitarianism is all well and good, however 'the real thing' is central to the accuracy of a reproduction system.
__________________
Ears aren't microphones.
  Reply With Quote
Old 3rd July 2013, 08:30 PM   #9657
nigel pearson is offline nigel pearson  United Kingdom
diyAudio Member
 
Join Date: Mar 2007
Location: Oxfordshire
Quote:
Originally Posted by davidsrsb View Post
Having spent hours in a room with real musicians rehearsing, you do not want the real thing at all.

The dynamic range of drums is way to high for domestic playback. Compression is essential
In Oxford it was two doors up where the orchestra rehearsed . Oxford Town Hall is not a good sound . All my recordings sounded better than the real place . I used the conductor's position to get that . However one piece of music defeated the buildings reluctance . The musicians also defeated their talent as if on some very dangerous drug , not one wrong note or timing . It was the most stunning musical experience of my life . The music built from nothing and seemed to have more pure sound that any hi fi or PA . This extract is pale although almost note for note identical ( texture also ) . It was so warm and brilliant ( sparkle ) . Hot for want of a better word . Love the magician ? I guess so .

Barenboim - "El amor brujo" (Danza ritual del fuego) Falla - YouTube

Last edited by nigel pearson; 3rd July 2013 at 08:34 PM.
  Reply With Quote
Old 3rd July 2013, 09:23 PM   #9658
nigel pearson is offline nigel pearson  United Kingdom
diyAudio Member
 
Join Date: Mar 2007
Location: Oxfordshire
Quote:
Originally Posted by bcarso View Post
Yes that was one of the silliest theories I ever saw, as if we had known nothing about solid state physics before the saucer crash etc.

I hear they did have some nice cables though
I love to unpick conspiracy theories . Not going to the moon . How could the USSR not say anything if true ?

UFO's . The RAF thought they might be the Soviets . When the USSR stopped so did the RAF investigations . Nothing unusual .

Philadelphia experiment . Too often the place they went to was another port . A bit odd it wasn't dry land if transported in time . Doubtless it was a high energy experiment . Doubtless they were sick bunnies if exposed to that . I suspect it even did what it was supposed to do a little . Problem is it still showed up on radar .

Roswell to cover up Supersonic testing when the USSR equivalents were unknown . Resolved after Korea .

John Titor . The laser beam/ LED in a tube showing total internal reflection . Not light bending due to time travel . Even with a low grade photo it is a tube . This photo is a little less clear than the one I saw . To say we couldn't do it in photo shop is the next point , we could . Anyway, if the light bends why not the structure bent and distorted ? Outside perhaps if fired through a window . They missed a trick with that one .

I forgot . Thermite in the Twin Towers . Not required as the materials are already there in the right proportions . That took me 5 minutes when I first saw it . Very sad anyone said that .

Hey Ho

John Titor Archive: Interview with a time traveler (images), page 1

Last edited by nigel pearson; 3rd July 2013 at 09:45 PM.
  Reply With Quote
Old 4th July 2013, 12:35 AM   #9659
fas42 is offline fas42  Australia
Banned
 
Join Date: Jun 2012
Location: NSW, Australia
Quote:
Originally Posted by Barleywater View Post
Frank,

The clip ends with long slab of track mixed into audio for video. Notice the camera panning and moving all over the place without variation in music.

Get yourself a measurement microphone and teach yourself something useful.
Do you actually believe that the end section is 'clean' audio mixed in with the video clip? If so, then that 'pure' audio is some of the poorest ever done!

Cameras have AGC, they constantly adjust the volume to suit, and there are numerous videos on the net where there appears to be no or very little "variation in music", with movement. I have done videos in a similar, relatively primitive way, and I hear exactly how that video comes across!

Hmmm, no-one has commented on what I'm after, I still need to do some close examination of the waveform to see if I can identify the characteristics that my ears are noticing ...
  Reply With Quote
Old 4th July 2013, 12:42 AM   #9660
fas42 is offline fas42  Australia
Banned
 
Join Date: Jun 2012
Location: NSW, Australia
Quote:
Originally Posted by davidsrsb View Post
Having spent hours in a room with real musicians rehearsing, you do not want the real thing at all.

The dynamic range of drums is way to high for domestic playback. Compression is essential
That's, why you have a volume control. You adjust to suit ... your mood, your desire to "rock out", etc. My personal experience is that once a system is producing "good sound" that the volume control is of no relevance to getting an "optimum" level - I can vary true output over a range of, say, 40dB, and subjectively the music doesn't change - I'm just nearer or further away from where the action is -- in other words, just like it is with live, acoustic sounds.
  Reply With Quote

Reply


Sound Quality Vs. MeasurementsHide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Quality Control differences = variations in sound quality? KT Class D 3 4th June 2014 12:02 AM
Sound Card for Measurements Marik Solid State 2 2nd January 2012 08:59 PM
Sound Card Recommendations (For Audio Measurements) dchisholm Equipment & Tools 5 16th July 2011 09:40 AM
How to protect sound card during amp measurements? okapi Everything Else 13 2nd September 2008 03:06 PM
Sound cards - test and measurements jackinnj Everything Else 2 5th July 2003 03:02 PM


New To Site? Need Help?

All times are GMT. The time now is 09:01 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki