guess i need to give up high-end hi-fi and see a psychiatrist for treatment of audiophilia nervosa.
i have been without my hi-fi for more than 2 months hence my lack of blogging.

what is suspected to be a sure case of weak power tubes has turned out to be.......

1st suspect - bad power tubes

so the frantic search for the best 6550s in the world sees me contacting jim mcshane (the tube guru in audio asylum), the tube store (an online tube supplier), martin electronics (s'pore), frankie (well audio lab, s'pore) and many other tube suppliers. i did 3 days of intense research on the internet on the availability of 6550s in the market. in the beginning, i was partial towards the new tungsol reissue 6550. both martin and jim have them in stock. but later i found out that this new tungsol comes from the same russian factory (owned by new sensor, US) that produces the grossly inferior svetlana 6550 and EH-6550. i was too scared to try new sensor tubes again. way too scared.

i was also tempted to buy the svetlana winged-c 6550 from the tube store; this being the more superior svetlana that audio research has been using for years. svetlana winged-c is produced by st.petersburg factory in russia and it is much better than new sensor's svetlana.

in the end, i took a gamble and settled for electro harmonix EH-KT90 for a change. according to ah chee of audio art, ipoh, KT-90s are direct plug-n-play with 6550s, all it takes is to rebias the tubes once. he claimed that KT-90s have sweet-tops and powerful bass. since i am an adventurous audiophile, i am game to try these new tubes, afterall audio research once used them in their amplifiers (eg. V140) in the mid-90s.

that was a month ago, i am still waiting for my tubes! damn it.

2nd suspect - ARC preamp

while waiting for the tubes to arrive, i took the trouble to do a proper isolation test by borrowing the same amplifiers - ARC classic 120 monoblock - from my friend. and horror of horror, i found out that my ARC power amps (and its tubes) are perfectly ok!!!! it was the ARC LS-25MkII preamp that is causing the slow and lethargic sound!!!

so i immediately sent the preamp to audio art, ipoh (where i bought it from) for a thorough check. it took ah chee two weeks before he could do a A/B comparison with another ARC LS-25MkII preamp from his customer. he said the preamp is perfectly OK too!!!

damn it. where is f**k is the problem then? audiophile nervosa can cause someone who seldom swears to swear a lot.

3rd suspect - loose power cords

when i brought home the preamp today, i immediately hooked it up and listen attentively again. fuck, the sound is still lethargic and slow! i leave it on for about one hour then suddenly, the sound gained energy and speed, but the overall sound is still very "moong" (blur), lacking the fantastic definition that my system used to have.

so i decided to check my various power cord connections.... damn it, the connection to the richard gray box seemed to be loose.... the hubbell 20A female plug of my harmonic tech AC-11 power cord doesn't quite grip tightly with the richard gray male IEC...could be this the real culprit that has eluded me for 2 months????

i tightened the contact and switched the system on again. omfg!!!! it was back, this is the normal sound of my system!!! omfg!!! omfg!!! i solved the problem, after 2 months of frantic and sleepless nights!!!!

omfg. i could not believe that i was so careless and neurotic to have omitted checking the basic things first.

i called ah chee and told him how i solved the problem on my own. ah chee broke into chuckles and warned me that the higher end you hi-fi is, the more susceptible it is to little little deviations. i think i have to give up high-end for good.

but first i am going to see a psychiatrist tomorrow.

==========

afterthoughts...2 days later

after listening to my system for 2 days, it is true that the sound never quite attains 100% of its optimal level. it does not sound lethargic but rather it has lost its sparkles and tightness. sure, it must be the weak tubes again so i wasn't over-reacting in the first instance. the 2nd instance of the preamp sounding slow was a genuine case of negligence. so i have no choice but to wait for my EH-KT90. what a bummer.

hope 2006 will be a better year for hi-fi!

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