Tube biasing question

[Big Dog RJ]

Met up with my tech this arvo and had an interesting discussion on tube circuits. So apparently CJ's circuits are based on the Classic tube circuits, which were designed around the 60's. Initially 50's and later on further refined during the 60's. Since that time, CJ hasn't really developed anything new from these "vintage circuits." Rather, what they've done is quite unusual, and that is just stick with the old and further simplified along the way, utilising the highest quality parts. CJ are probably the only ones that have perfected this circuit and execute it extremely well, so why change what works!

Compared to ARC, this is where research, innovation and breakthroughs are made. They basically stand for audio developed through research and their circuits are highly advanced and in certain pre-amplifier stages quite complicated. When getting into ARC, you really need to know what you're getting into and how ARC recommends tube changes, matching, biasing etc.

Amongst these two, according to what he's seen, serviced, fixed, modded, and upgraded over several decades, CJ and ARC are second to none. The others he claims are rubbish, very mediocre and poor sub-standard curcuit design.

Since these are proprietary circuits and patented designs, others can't get a hold of them but they certainly do try to copy them in certain areas. However, they still don't quite get there... power may be high but current lacking, ability to drive through 8 to 6 Ohms but anything less, they fail. This is where proper power supply design is lacking.

When it comes to CJ and ARC, they are the most stable and reliable tube circuits you will ever come across, and their power supplies don't flinch one bit. No wonder this is the price we pay... so might as well.

Cheers to CJ & ARC!
Enjoy those fine tunes !
RJ

[AnotherJohnson]

In the ARC anniversary book, it was stated that Bill Johnson would not listen to competing products to reverse engineer their sound. He purposely ignored what others were doing, relying instead on his own sonic goals.

The book said he loved vinyl. He hated the saxophone (so not much tolerance for much of the jazz genre). Early on he established an official corporate listener. EVERY SINGLE UNIT IS LISTENED TO BY THE OFFICIAL LISTENER. If it doesn’t pass his ears, it goes back for rework.

Bill thought he would have to steer the company away from tubes and into solid state, but tube availability improved. He said he could make SS sound good, but for the same level of development effort, he would always be able to get better sound out of the tube based design.

[admin]

Both CJ and ARC made great sounding equipment. It's ok to achieve a desired goal via different routes. Invention vs refinement, who is to say what is better in the end?

[AnotherJohnson]

I think CJ and ARC can both be considered legitimate “boutique builders,” but CJ even more so than ARC. Boutique in the guitar industry tends to mean a small shop with skilled artisans practicing their craft.

CJ style borders on Art Deco. ARC is more Hospital/Industrial.

Simple circuits with the best parts to achieve “it just sounds right sound” is CJ’s mantra.

ARC circuits may be more innovative, and appear to my ears to be “higher definition”. Parts quality is important, but not really an advertising theme.

Both companies put a BIG emphasis on the power supply and transformers.

Both use solid state devices in some of the sub circuits in nominally tube components.

Both have attentive service departments if there are issues with current or relatively recent products.

Both are privately held.

They’re different … but both strike me as excellent.

CJ takes a minimalist approach to features. They’ve bowed to consumer demand for remote control. But they balk at remote control of the on-off function, hour meters, remotely adjustable cartridge loading, or any feature that requires a menu. No power meters. No exterior transformer tap options. No big displays.

ARC gear is often feature laden. More to go wrong I suppose. More parts to stock for repairs. More overhead in general.

Both are expensive. Neither has a very good dealer network, though ARC’s seems a bit more fleshed out. A lot of CJ’s dealers are Mom & Pop operations with only one or two employees. Sometimes they’re willing to wheel and deal.

I’ve enjoyed components from both companies over the years, but only recently have systems based on each simultaneously. My reaction to having both is that they’re both really enjoyable.

It is a small issue in the grand scheme of Russian hegemony, but I wonder if either or both will be casualties of the lack of a tube industry among nations friendly to the US where both CJ and ARC reside. If they fail, it will be tragic … but nothing compared to what’s happening to humans in the line of fire.

[mstrshikadance]

Hey All. I am interested in one of these tube bias meters to mess around with https://www.amazon.com/Nobsound-Current ... 309&sr=8-5

What range would be the expected properly biased mA in a Premier 11 using 6550?

[AnotherJohnson]

It’s probably smack dab in the middle of that ammeter.

[admin]

Hey All. I am interested in one of these tube bias meters to mess around with https://www.amazon.com/Nobsound-Current ... 309&sr=8-5

What range would be the expected properly biased mA in a Premier 11 using 6550?

You can still bias the unit with that meter. I'm not sure how many mA the Premier is spec'd at but put the meter in, bias it with the LED on the unit. Do a few tubes. You should get a reading on what the LED's bias set point is. Then just use that value.

This is a nifty toy, but don't ignore the LEDs.

[roberto]

The Company Conrad Johnson was founded in 1977 with their first product, the PV-1 preamplifier that launched in that year. These great guys, Bill and Lew had a small garage where they did all their electronic research, their design and started to build their Company. The circuity used on their products are their own design and investigation. They do developed new circuitry topology, and also they made an incursion into the SS design world and digital gear. Their CDs are Philips base electronics, with the analogue circuit made by them using CMos FET transistors. The FET behavior is very similar to the vacuum tube.

The research on new circuitry is still under investigation. Claiming that they are old circuit design...all electronic device is an old design too in analogue signals. Factories and designers use common base circuitry also on these days . The research on electronics had brought to us components with fantastic characteristics, specially in SS. The SS is used to maintain stable voltages where with the tubes are not possible as it is in the SS world.

So, what's the fuzz with tubes? Tubes have the harmonic distortion on the second order (even). The second order distortion makes to sound of the trumpet a trumpet, and the guitar a guitar, the piano a piano...and goes beyond than that. A piano sounds different than another piano, having a very similar timber. All instruments and also our voices have a distinguish tone - timber. The tubes, because of their even distortion, reproduce this with much detail and right with the timber. This is the main reason why we love tubes. When you listen Golden Tube brand, or Cary Audio, Carver, Audio Research, Rogue, VAT, VTL, to mention some tube gear makers, they have their own signature sound quality.

New components and doing a better recipe on the design gives us the quality sound. If the circuitry is the same, why do they sound different and why the new models? And why are so many different brands with different sound on their components? If using good parts that are available for all audio makers, why they sound so different?

The big problem of our beloved hobby is that the sound is logarithmic and our electronic gear is linear. This is the thing.

Happy listening!