IPB

Welcome Guest ( Log In | Register )

 
Reply to this topicStart new topic
Doug Self preamp gets rough ride, An example of the destructive effects of unmoderated subjectivism
wakibaki
post Aug 15 2012, 09:39
Post #1





Group: Members
Posts: 37
Joined: 23-July 11
Member No.: 92474



http://www.diyaudio.com/forums/solid-state...-design-53.html

In the latter half of this thread, moderators defend the right of posters to undermine the reputation of the latest design from this outspoken opponent of subjectivism, based only on unsupported subjective opinion. Well-known designers and respected analog 'gurus' lend their tacit support by participating in the thread.

w


--------------------
wakibaki.com
Go to the top of the page
+Quote Post
wakibaki
post Aug 15 2012, 15:04
Post #2





Group: Members
Posts: 37
Joined: 23-July 11
Member No.: 92474



The principal author of the libel, one 'owdeo' earlier admitted 'I know this is not double-blind testing' and 'This may not be a scientifically valid test, but I think it was good enough to prove (to me anyway) that the difference in sound quality I was hearing earlier is real.'

Later he claimed 'I've done some blind testing and had no trouble picking the preamp'. When questioned on the subject he also admitted that he had not verified that the amplifier he had built met its design specification.

Owdeo claims 'as an EE' but confusingly said in the same post that he has only basic knowledge of electronics.

Nevertheless he insisted that the design was unsatisfactory, describing it in terms of the usual subjective twaddle saying 'The sound is still slightly "tight" or "overdamped" or something,', 'I know it's purely subjective and unscientific, but the difference is so big I'm sure it must be measureable if you could measure the right thing with the right equipment.'

These occasional smatterings of techno-bullshit and the pretence at blind testing evidently have all but a few at diya completely hornswoggled.

Meanwhile, diyaudio's reputation as a responsible organ (if it ever had one), continues to suffer.

Doug Self, who had earlier contributed to the thread, has ceased to post.

w


--------------------
wakibaki.com
Go to the top of the page
+Quote Post
Arnold B. Kruege...
post Aug 15 2012, 15:33
Post #3





Group: Members
Posts: 3534
Joined: 29-October 08
From: USA, 48236
Member No.: 61311



QUOTE (wakibaki @ Aug 15 2012, 10:04) *
The principal author of the libel, one 'owdeo' earlier admitted 'I know this is not double-blind testing' and 'This may not be a scientifically valid test, but I think it was good enough to prove (to me anyway) that the difference in sound quality I was hearing earlier is real.'

Later he claimed 'I've done some blind testing and had no trouble picking the preamp'. When questioned on the subject he also admitted that he had not verified that the amplifier he had built met its design specification.

Owdeo claims 'as an EE' but confusingly said in the same post that he has only basic knowledge of electronics.

Nevertheless he insisted that the design was unsatisfactory, describing it in terms of the usual subjective twaddle saying 'The sound is still slightly "tight" or "overdamped" or something,', 'I know it's purely subjective and unscientific, but the difference is so big I'm sure it must be measureable if you could measure the right thing with the right equipment.'

These occasional smatterings of techno-bullshit and the pretence at blind testing evidently have all but a few at diya completely hornswoggled.

Meanwhile, diyaudio's reputation as a responsible organ (if it ever had one), continues to suffer.

Doug Self, who had earlier contributed to the thread, has ceased to post.


I am unaware of when DIY Audio was a reliable source for the results of reasonable subjective tests.

You've hit one of my hot buttons - unreliable subjective testing is usually a cover for libeling good audio gear. I suspect that the perps mean well, but what they do is mostly creating and/or propagating false claims.
Go to the top of the page
+Quote Post
Canar
post Aug 15 2012, 16:34
Post #4





Group: Super Moderator
Posts: 3327
Joined: 26-July 02
From: princegeorge.ca
Member No.: 2796



Now I want to try this preamp! I'm not big on the whole preamp thing in general, but hey, if it pisses off subjectivists...


--------------------
∑:<
Go to the top of the page
+Quote Post
Arnold B. Kruege...
post Aug 16 2012, 12:35
Post #5





Group: Members
Posts: 3534
Joined: 29-October 08
From: USA, 48236
Member No.: 61311



QUOTE (Canar @ Aug 15 2012, 11:34) *
Now I want to try this preamp! I'm not big on the whole preamp thing in general, but hey, if it pisses off subjectivists...


I have a copy of "Self On Audio" second edition, which contains the 1996 preamp articles. The genius of the preamp is IMO not any special innovations, but rather the careful and clear way that Self explains how he optimized a pretty common and straight forward design. Basically, he's exploiting the fact that the now sub- 50-cent 5532/5534 op amp chips are really very, very good.

By now the chip design has to be more than 30 years old, but it still shows up in new equipment designs. In the day, many of us merged these chips with the most recent wisdom from Vanderkooy and Lipshitz about RIAA networks and pretty well cook-booked our ways into our last phono preamps. Nothing ever emerged that sounded better for use with MM cartridges, to this day.
Go to the top of the page
+Quote Post
greynol
post Aug 16 2012, 13:23
Post #6





Group: Super Moderator
Posts: 10000
Joined: 1-April 04
From: San Francisco
Member No.: 13167



Tight and overdamped? Since when does a preamp take on the characteristics of a poweramp driving speakers?


--------------------
Your eyes cannot hear.
Go to the top of the page
+Quote Post
Arnold B. Kruege...
post Aug 16 2012, 14:26
Post #7





Group: Members
Posts: 3534
Joined: 29-October 08
From: USA, 48236
Member No.: 61311



QUOTE (greynol @ Aug 16 2012, 08:23) *
Tight and overdamped? Since when does a preamp take on the characteristics of a poweramp driving speakers?


Trying to decode the stilted subjectivese, I came up with the idea that this listener's baseline for a phono preamp had a RIAA preamp that over-emphasized the bass due to an equalization error.

That would be a little surprising because the most common tech errors in RIAA preamps usually end up causing bass that is thin-sounding.

OTOH the Self design has an effective subsonic filter which would avoid some common kinds of excess bass due to tone arm resonances and/or incipient feedback due to a lack of acoustical or mechanical isolation.
Go to the top of the page
+Quote Post
greynol
post Aug 16 2012, 14:37
Post #8





Group: Super Moderator
Posts: 10000
Joined: 1-April 04
From: San Francisco
Member No.: 13167



So this was about a phono preamp? The OP and tilte were vague in this regard.


--------------------
Your eyes cannot hear.
Go to the top of the page
+Quote Post
Arnold B. Kruege...
post Aug 16 2012, 17:12
Post #9





Group: Members
Posts: 3534
Joined: 29-October 08
From: USA, 48236
Member No.: 61311



QUOTE (greynol @ Aug 16 2012, 09:37) *
So this was about a phono preamp? The OP and tilte were vague in this regard.


It is about a complete traditional preamp including phono input, line level input(s) and tone controls.
Go to the top of the page
+Quote Post

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 



RSS Lo-Fi Version Time is now: 16th April 2014 - 23:50