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A collection of anti-hifi [ripoff] information, cables, tweaks, expensive equipment...
jrbamford
post Sep 5 2003, 11:44
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I've often wrestled with the issue of hifi and whether its worth it or not...

I do believe they're are improvements to be had by spending a bit more... compared to an all in one mini system from an electronics store at 300 or more... or rather i used to believe it... its often difficult to try to even persuade hifi people to even consider the possibility of this.. obviously there is an element of protecting your investment in hardware (similar loyalties run deep in games consoles wars etc)...

Anyways i've seen links and discussions on this before, i thought it'd be good to try and collect all of this in one place.. I'm sure somewhere i got a stereophile article off someone on here (dibrom?!) about a blind test they did with interconnect or spaeaker wire.. using real cheap wire compared to some mid range hifi interconnect... few people managed to spot it... if any blindly...

Its this kind of information that'd be great to have to try and let people read about it and at least consider to potentially save them more money... so any articles, links to tests done or discussions would be great.. other than just informed discussion on this thread or links to other threads would be great...

Firstly i think it'd be good to confront the wires issue... leaving whether certain hifi equipment is even useful or not.. this kind of information would be more easily absorbed by hifi-ers than telling them that there really is no need to buy an expensive cd player if you already have one... also with dual output devices (my DAC has two outputs) its much easier to easily let ppl setup two interconnects and quickly switch to do some blind testing...

Thanks


--------------------
Binaural recordings of mine: http://binaural.jimtreats.com
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Pio2001
post Sep 20 2003, 01:23
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Speaker cables recordings.

Don't try this at home unless you have a diploma about electric engineering !!!

I recorded the speaker signal delivered by my ampli at the ampli plugs and at the speaker plugs, with three different speaker cables, with a coaxial cable connecting the speaker plugs into the line in of my DAT deck (47 kOhm standard line in).
The tricky part : if you mistake the + for the -, you fry your amplifier connecting the positive speaker out to the ground of your recorder !

The samples are mono, because I didn't have enough coax to reach both speakers.
They are available at http://www.hydrogenaudio.org/forums/index....=13401&st=0
I made 4 samples.
-Recorded from the ampli (Arcam Diva A85), with double A2 cable (12 mm2 solid core copper), about 4 meters long, with a Dynaudio Gemini speaker (4 ohm).
-Same thing recorded from the speaker
-QED Qudos cable (4 mm2 stranded copper), 4.5 meters, speaker side
-Same thing with 6.5 meters of cable

The RMS levels (over 123 seconds of recordings, while you have only 20 seconds samples) are :
Ampli : -16.64 dB
Speaker / A2 : -16.64 dB
Speaker / QED short : -16.68 dB
Speaker / QED long : -16.70 dB


Compared spectrum analysis.

I made Samplitude draw the spectrums over the 123 seconds recordings, with the same settings. I then superimposed them in additive mode and colors inverted.
As a result, you get the A2, QED long and QED short spectrums compared to the ampli spectrum.
White lines are identical levels. When you see red pixels at the top, then the speaker signal is louder (the cable emphasizes this frequency). If you can see cyan pixels, the ampli signal is louder (the cable attenuates this frequency). Look closely in order to see the tiny pixels !
One pixel equals 0.1 dB. I counted the pixels moving the layers step by step until the pixels change colors in Corel Photopaint.



Above, the A2 cable gives up to +0.15 dB between 3 and 8 kHz, and up to -0.2 dB above 8 kHz



Above, the short QED gives up to -0.2 dB above 8 kHz



Above, the long QED gives up to -0.3 dB above 8 kHz

If we assume that the speaker impedance can fall as low as 3 Ohm, and that the ampli impedance is 0.08 Ohm, then, the long QED cable being about 0.07 Ohm ,skin effect (20 kHz) taken into account (4mm2, 13 meters), just to get an idea (anyway the real speaker impedance is unknown), it should give
U'/U=(3+0.08)/(3+0.07+0.08)=0.98
Loss = 20 log (0.98) = -0.2 dB

Thus the differences measured can be explained by the speaker impedance and the cable resistance only.

ABX Listening tests on the samples (8 sessions each ) :
Long Qed vs Ampli signal : failure (I don't remember my bad score)
A2 vs ampli signal : failure (5/8).


Edit : pictures links

This post has been edited by Pio2001: Nov 17 2008, 21:35
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Posts in this topic
- jrbamford   A collection of anti-hifi [ripoff] information   Sep 5 2003, 11:44
- - ScorLibran   I like this idea! I've often wondered whe...   Sep 5 2003, 12:22
- - jrbamford   QUOTE And I've seen similar tests on cabling, ...   Sep 5 2003, 12:39
- - boojum   Wire is wire is wire. Heavy duty lamp cord will s...   Sep 5 2003, 13:36
- - 2Bdecided   It does cost money to do some things well. And it ...   Sep 5 2003, 13:45
- - jrbamford   QUOTE Wire is wire is wire. Heavy duty lamp cord w...   Sep 5 2003, 13:58
- - 2Bdecided   See my reply in the turntable thread. And if that ...   Sep 5 2003, 14:10
- - fewtch   Cable capacitance is also a big issue with moving ...   Sep 5 2003, 14:28
- - jrbamford   Thanks fewtch, i did wonder.. the one lead i would...   Sep 5 2003, 15:34
- - fewtch   I'd suggest using any well-shielded audio cabl...   Sep 5 2003, 15:51
- - jrbamford   The turntable i got has RCA inputs anyways so that...   Sep 5 2003, 16:23
- - DonP   In the case of phono: if your preamp/receiver can...   Sep 5 2003, 16:43
- - fewtch   QUOTE (jrbamford @ Sep 5 2003, 08:23 AM)So au...   Sep 5 2003, 17:05
- - Audible!   Speaker cable "differences' over average ...   Sep 5 2003, 23:01
- - jrbamford   Thanks Audible! great link.. thats what i...   Sep 5 2003, 23:35
- - Audible!   QUOTE wierd as he does sell these things yet says ...   Sep 6 2003, 00:53
- - ChrisGranger   I would like to see a properly conducted ABX test ...   Sep 6 2003, 10:22
- - ChrisGranger   Oh, and to reply to the initial post, I really thi...   Sep 6 2003, 10:34
- - DarkAngel   I lost almost all faith in high end hi-fi magazine...   Sep 6 2003, 11:43
- - Patsoe   QUOTE (jrbamford @ Sep 5 2003, 11:44 AM)...An...   Sep 6 2003, 23:39
- - polandro   If you want a link to a snake-oil type site try C...   Sep 7 2003, 00:23
- - Audible!   QUOTE It's silly. Do they rewire their CD play...   Sep 7 2003, 00:29
- - Bongoboy   QUOTE (jrbamford @ Sep 5 2003, 11:44 AM)Anywa...   Sep 7 2003, 00:50
- - Bongoboy   QUOTE (Audible! @ Sep 7 2003, 12:29 AM)Go...   Sep 7 2003, 01:24
- - Audible!   QUOTE First of all Galvanic Corrosion (or electrop...   Sep 7 2003, 02:03
- - Auric   I certainly think there's a difference, but on...   Sep 7 2003, 16:10
- - Audible!   QUOTE In other words, as long as long as the speak...   Sep 7 2003, 21:41
- - Bongoboy   QUOTE (Audible! @ Sep 7 2003, 02:03 AM)Th...   Sep 8 2003, 01:34
- - Bongoboy   QUOTE (Auric @ Sep 7 2003, 04:10 PM)The same ...   Sep 8 2003, 02:12
- - Pio2001   Could someone post the equivalence between AVG and...   Sep 17 2003, 23:00
- - DonP   QUOTE (Bongoboy @ Sep 7 2003, 08:12 PM)The re...   Sep 18 2003, 00:58
- - sthayashi   QUOTE (Pio2001 @ Sep 17 2003, 02:00 PM)Could ...   Sep 18 2003, 05:38
- - Audible!   QUOTE Should I drop the cash and get more expensiv...   Sep 18 2003, 05:48
- - monkeyboy   Most copper is 99.9% Oxygen free. The main differ...   Sep 18 2003, 16:31
- - Audible!   QUOTE Now, whilst the listener may not instantly p...   Sep 19 2003, 00:01
- - jrbamford   I plan to record some outputs from my DAC20 (with ...   Sep 19 2003, 00:17
- - KikeG   At http://www.kikeg.arrakis.es/stest you have a te...   Sep 19 2003, 07:48
- - JeanLuc   QUOTE (Auric @ Sep 7 2003, 03:10 PM)The same ...   Sep 19 2003, 10:21
- - ScorLibran   Out of curiosity, I am wondering what any (theoret...   Sep 19 2003, 10:40
- - 2Bdecided   QUOTE (ScorLibran @ Sep 19 2003, 09:40 AM)Or ...   Sep 19 2003, 10:57
- - KikeG   QUOTE (ScorLibran @ Sep 19 2003, 10:40 AM)Onc...   Sep 19 2003, 11:00
- - JeanLuc   QUOTE (ScorLibran @ Sep 19 2003, 09:40 AM)I *...   Sep 19 2003, 11:47
- - KikeG   QUOTE (JeanLuc @ Sep 19 2003, 11:47 AM)there ...   Sep 19 2003, 12:27
- - kennedyb4   This is a great thread. There have been many claim...   Sep 19 2003, 12:57
- - DonP   QUOTE (KikeG @ Sep 19 2003, 06:27 AM)Not most...   Sep 19 2003, 13:26
- - JeanLuc   QUOTE (KikeG @ Sep 19 2003, 11:27 AM)even if ...   Sep 19 2003, 14:00
- - KikeG   QUOTE (JeanLuc @ Sep 19 2003, 02:00 PM)That...   Sep 19 2003, 14:20
- - bawjaws   A condensed version of this thread and the informa...   Sep 19 2003, 14:31
- - JeanLuc   QUOTE (KikeG @ Sep 19 2003, 01:20 PM)As I exp...   Sep 19 2003, 14:33
- - KikeG   QUOTE (JeanLuc @ Sep 19 2003, 02:33 PM)they c...   Sep 19 2003, 14:58
- - Pio2001   Skin Effect Summary. The skin effect in a cylindr...   Sep 19 2003, 22:06
- - Audible!   Very informative post Pio! QUOTE The usual r...   Sep 19 2003, 23:29
- - ChrisGranger   QUOTE (Audible! @ Sep 19 2003, 05:29 PM)Q...   Sep 20 2003, 01:01
- - Pio2001   Speaker cables recordings. Don't try this at ...   Sep 20 2003, 01:23
- - Audible!   QUOTE Loss = 20 log (0.98) = -0.2 dB But, but, but...   Sep 20 2003, 01:37
- - Pio2001   Then, looking at him you can ABX ?   Sep 20 2003, 03:10
- - Audible!   QUOTE Then, looking at him you can ABX ? Well, not...   Sep 20 2003, 03:37
- - ger@co   QUOTE (sthayashi @ Sep 17 2003, 10:38 PM .)Mo...   Sep 20 2003, 06:01
- - lucpes   The audio signal is alternative current, so it doe...   Sep 20 2003, 19:27
- - Audible!   QUOTE However, the "warm fuzzy feeling" ...   Sep 20 2003, 21:27
- - Pio2001   QUOTE (lucpes @ Sep 20 2003, 09:27 PM)The aud...   Sep 20 2003, 21:50
- - lucpes   QUOTE (ger@co @ Sep 20 2003, 05:01 AM)If you ...   Sep 20 2003, 22:05
- - Welly Wu   I certainly respect the opinions of my fellow HA m...   Sep 20 2003, 22:10
- - lucpes   QUOTE (Welly Wu @ Sep 20 2003, 09:10 PM)Furth...   Sep 20 2003, 22:25
- - fewtch   Welly Wu, I'll allow that cables may make a d...   Sep 20 2003, 22:25
- - lucpes   QUOTE (Welly Wu @ Sep 20 2003, 09:10 PM)...I ...   Sep 20 2003, 22:29
- - Audible!   QUOTE However, I agree to disagree that with respe...   Sep 20 2003, 22:35
- - Pio2001   QUOTE (Welly Wu @ Sep 21 2003, 12:10 AM)juxst...   Sep 21 2003, 00:04


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