TUBE BIAS, socket to me!


BIAS: (I'm starting from zero understanding) 

I have never measured/adjusted bias in the 3 tube amps, 3 tube receivers, and 2 tube preamps I have acquired over 47 years. I just switched my current Cayin from 6550's to KT88's. Adjust bias? Adjusters inside, scary electrocution warnings. I could pay someone else to do it, i.e. Steve at VAS 1 hr away in NJ, soooo, 

What really counts? (personally I don't care about either heat or life, but would like to understand)

Heat?
Life?
Output stays Matched when adjusted?
Acoustic Performance?
_________?

Over the years, fronts off, bottoms off, I hose em down with contact cleaner/lubricant, compressed air, all controls and switchers, any adjusters, swish full spin back and forth. Kill any spiders, look for, replace the rare burnt resistor. 
Then leave any adjusters (whatever they are) in the middle position, button it back up.

Two tube testers, my big hickock always agrees with small portable one, test strength, shorts, matched strength old and newly purchased. Large collection of NOS, used. Often used test essentially same strength as new ones.

When they go, it's usually a short.
elliottbnewcombjr

Showing 9 responses by sokogear

Vintage, classic, antique or old, heavily used, low tech, rebuilt? The words you show your bias.

New, high tech, modern or unproven, bleeding edge, trendy? Same thing.

I can’t stand the Marketing BS.
Gotcha @lewm. So what user involvement would be involved with normal routine maintenance/upkeep of tube equipment of 2000 vintage or later? Testing, rolling, cleaning, biasing, replacing, etc.

For analogue, I have to get a new stylus (or cartridge) every 2-2500 hours of use.Maybe change a belt after 10 years. I’m not aware of direct drive tables needing anything.
Thanks Lewm. I am hoping to hear from people who have tried or use both and their reasons for choosing tubes over SS. There was a similar discussion on analogue vs. digital and it was interesting to hear both sides opinions.
Is it really worth all this fuss? Can't you find a solid state amp that sounds as good or better, or are tubes less expensive for a given sound quality?

Don't shoot me - I am a vinyl guy, so certainly willing to go through some inconvenience for top SQ, but ever since I was in a room with tubes that got so hot a fan had to be installed (ruining the sound of the stereo), I never considered them.

I like to think I am open minded. Convince me why I should change my Plinius 8200MKII integrated amp to a tube one.
@elliottbnewcombjr - aren't all audiophiles by definition fussy? If you don't care about high SQ I doubt you would categorize yourself as an audiophile. You didn't say why you prefer tubes, if you ever had them in your system, when that was, etc.

Your description (testing tubes, spraying tubes, replacing tubes, etc.) sounds like more to do than I currently do with my amp, which is nothing other than leave it on all the time (after 15 years I hope I am not jinxing myself) except to turn it off when the cleaning lady visits, just out of paranoia, even though she knows not to touch anything in the stereo. I am scared she or one of her girls might bump into something by accident.

@elliottbnewcombjr- I’m not defending SS- its all I’ve ever used. The stereo dealer I trust most told me it depends on the amp more than the technology. Tubes tend to cost a bit more for a given SQ. As I said, my only experience was listening to tubes when the room heated up significantly. Just like belt vs. direct drive TTS - it depends on the table.

I think you are fussy, and an audiophile. My wife and kids think I’m nuts, but I think I am practical and believe in the law of diminishing returns. I’m not an upgraditis guy spending 10’s of thousands on a whim for the latest and greatest. I didn’t get a record cleaning machine because my records are in perfect shape (mostly) and when a dealer had me bring some records in and compare the sound before and after cleaning, I couldn’t hear a difference. I don’t buy old used records unless they are NM or unopened.

Since I leave my amp on all the time I’ve drank  the kool-aid? What does that mean?

I do use a power conditioner- things have to be plugged in somewhere, right? Got a good Furman one used for $300. No dedicated circuits, but I don’t think there are any things being used on the circuit except my amp, phono stage, turntable, tv, and cable box.

I recently vastly improved my turntable by first putting an isolation platform under it. I was convinced by a frequent AG contributor (MC) who swore by it. I was very skeptical about that tweak, but it made a dramatic improvement, like a new turntable - more detail, depth, bass, and to remove foot faults because of my suspended floor over a crawl space put a wall shelf in for my turntable. Of course foot faults went away and the sound improvement was subtle if anything. 
My one interconnect was $200, power cords were all about $100, and my speaker cables were about $500.

No other tweaks other than Herbie’s tenderfeet under my amp and phono stage ($100 total). That was a more theoretical improvement purchase as keeping wires perfectly still does improve the sound, but the question is, can you hear it? Probably not.
My speaker sensitivity is 88dB, so maybe I shouldn’t consider tubes. MC says not to buy speakers under 92dB. I think he goes overboard sometimes.

You hit the nail on the head though, so much is dictated by the room. 
I am thinking that if I follow my rule of not doing any component upgrade unless it is a NOTICEABLE improvement and under $1K net after trade, so I’ll probably stick with my Pliniuis.

i don’t know how old you are, but I think some people who grew up with tubes prefer them. I grew up with vinyl, built a nice collection and tried CDs and didn’t think they even came close to records.
Now your talking electrocution precautions? Come on.... it can’t be worth it.

i guess as a physics lab hobby, its OK- I’d rather listen to music than play in the lab with tubes. 
I had physics lab in college 40 years ago. No desire to go back there.
Thanks @lewm. You didn't mention about tube testing - how often? I did think tube rolling was kind of just fooling/playing around, especially with newer tube amps.

Day to day, of course, brushing the records and getting up to flip them every 20 minutes (or 10 with 45's) and handling the records (dealing with the sleeves, jackets and external sleeves and filing and removing them) is more time consuming than CDs, let alone streaming, but at this point, it is kind of a ritual.

Do all tubes heat up the room, or is that a design function as well, the harder they run?

Lastly, I have a SS phono stage. Does this reduce the potential benefit of an integrated tube amp? I got this about 9 months ago as before I used one in my integrated that was only adjustable between MM and MC with no variation on load or gain.I never knew how much better my system would sound with a dedicated phono stage versus the one that came with my amp.

When I bought it, the cost of tube phono stages was substantially higher than SS ones, and I was told the lower cost tube ones were "noisy". Is this the case with integrated amps as well?

Just doing some longer term planning/thinking.

Thanks for your opinion.