The Fumbling Audiophile

HiFi Basics XI: Elementary Errors and the Fumbling Audiophile

We know Newbies in HiFi run into a lot of problems, but what about Experienced Audiophiles? I tell you, all of them (us) fumble from time to time, for no good reason. First of course, there is Murphy's Law, which means when your buddies come to listen something will almost always go wrong. But we are not talking about that. Let me relate to you two of my embarrassing fumbles this past year.

1. Almost a year ago, I took out my Almarro A318B (pictured; click to enlarge) for a run. The machine heats up the filaments for almost 2 minutes before unmuting itself. Soon I heard popping sound in the left channel and shut it down. The same the second time. It also would not bias (recommended is 0.18V; no more than 0.21V). I got frustrated and put it back into the box. Recently I decided to get a new matched pair of 6C33C, and they are not cheap (over $100). I installed the stock Russian 6SN7 and 6SL7 and ran the new tubes. Great music, no bias problem. The next day, I installed the same 2 old-stock N7/L7 which I have kept in the box, expecting a better sound. Guess what, a pop in the left channel! I went to test the N7/L7. The L7 tested great. The N7 passed but for one triode I saw the meter drift erratically in both directions. There! That 6SN7 is faulty! Yes, tubes can measure well and still be faulty, particularly when warming up. I exchanged it with a RCA 5692 and the sound was perfect. Humbled, I reflected on why I had assumed it was the 6C33C that was at fault. Why had I not considered the possibility of either of the small tubes being the culprit? Perhaps the biasing problem compounded my confusion. Yesterday, I swapped in the original pair of of 6C33C and, guess what, they worked perfectly. And this time, there is no bias problem; in fact, they bias just like the new pair. Well, what happened back then? Unlikely as it is, I could only surmise that the faulty tube somehow messed up the bias. Well well, this is as it should be. I never used this amp that much and the stock tubes still should have plenty of life left (especially since I now run them at only 0.13-0.15V bias; mind you in NYC my area voltage can be 126V, dangerously near the tolerance limit of gears designed for 117V +/- 10%). I could have saved $100 if I had been more thorough before.

In case you want to know in advance, the Almarro works gloriously as an integrated amp with the Harbeth P3ESR SE.

2. About half a year ago, I decided to fire up my AES-1 300B amp. It would not turn on (not even filament). I thought it was likely a rectifier (solid state) problem and took it to my friend Paul. Some time later, when he got to it, he said it was the fuse, and that it sounded pretty good! Now, that really was an inexcusable error in judgement. Not checking the fuse when something refuses to turn on! Elementary, my dear Watson! I have probably connected and disconnected, assembled and disassembled things more times than I have eaten a meal, and I forgot to check that?

Incredible as it may seem, it happens to everyone. We are too smart or over-confident for our own good. We assume things based on our incomplete knowledge and experience, which result in imperfect algorithms. Advice: be methodical always and don't jump to conclusions. 

When there is no Sound or just Hum This is unquestionably the most common problem, particularly when we are changing components. The more complicated the system, the more components hooked up, the greater the likelihood. The more things we change in a short period, the more likely too. Some pointers:

• This is least likely to happen when we just change the amp. If it happens, do check the fuse of the amp. Turn off can sometimes blow the fuse (such was the case with my AES-1, as it worked well the last time I used it many years ago). Fuse can fail for no reason, but if it blows twice in succession, don't try again and get help (make sure the ratings are the same, and distinguish slow-blo from the regular fast-blo).

• Changing anything else in the chain is a different matter. People like me don't turn the amp off (I don't usually use an integrated). I'd keep the amp on and just turn the Input Selector to the next position (mute button is less common). Now, depending on what is changed, component or cable, the selector can be the one on the preamp, DAC or Phonoamp, and that can cause confusion, particularly when your visual access to the rack and cables are limited. Compound that problem with my habit of leaving unused interconnects around the back of the rack, and it can make for a confused scenario. It is not uncommon to see big guys crawling on their stomachs for up to a half hour before finding that little switch is in the wrong position. Advice: check all your selectors and switches. With vintage stuff, the problem is compounded by the unreliability of the contacts, which often cut out. With old preamps that have tone control and loudness and monitor switches, any of those can result in bad contact and no sound. Flip them on and off diligently.

• Mating of the RCA Connectors can be an exasperating problem (which is why professionals use XLR or BNC and other even more sturdy ones). Just like in the human world, NOT every RCA Female could happily couple with every Male. Now, this is not lewd, but the truth. The Female RCAs vary somewhat in outer ground collar (metal) diameter (and pliancy), and the hole diameter and tightness (pliancy of teflon or polymers). The Male RCAs also have varying diameters of their hot pins and their outer collar vary greatly in pliancy. A stud hot pin with a tight outer grip will mate well with a Female RCA that can grip it well. On "high-end" equipment, the mating is usually good, but, with the technical contact solved, is the resultant "sound" always good? Many, like the vintage inclined, the Japanese and I (and mrgoodosund I think), do not think so. Personally, I think WBT, Cardas posts, thick spades and the likes degrade the sound because of their large metal bulk and contact area. Some are better though, like Eichmann Bullet Plug (now named something else) but they are expensive and tend to ruin vintage or generic females found on many of our preferred machines. This problem is compounded several folds if we mix modern and vintage, as I do. Many vintage female connectors, including those used on Shindo (for their sound), tend to lose elasticity dues to the relative softness of the insulating material, which deform after repeated penetration. One has to wiggle gently to see if contact can be established. Sometimes wedging a slab (I use paper roll) between the R and L connectors will make the penetration angled and made the females happy. Like humans, not every RCA connector is the same. Another example. Just the other day, my LTA (used as preamp) and Wavac could not mate and had a loud hum. I had to try 3 interconnects to solve the problem. My cherished KCAG with my favorite connector and old AN AN-Vx would not make contact unless at certain angles. An An-V solved it (and it sounds good). Come to think of it, with generic cables that come with TVs, computers, gaming stuff etc, NO ONE has ever experienced any problem. BUT, the so-called audiophile stuff are all over the place, often incompatible. A condemnation.

There are a lot more stupid instances, but that will be enough for now,