Wanted: Joule Electra VZN-220 Rites of Passage

DaveyF · Oct 31, 2017

morricab said:
Hi Ron,
I know I mentioned these to you in another thread but I tell you honestly you have never felt heat from amps like amps with a bunch of 6c33C tubes!

I had the very excellent sound Silvaweld OTL reference monoblocks many years ago and they had "only"4 x 6C33Cs per channel. I had to get rid of them because after a couple hours of running they had my room a good 10 degrees hotter! I was having to listen in my underwear!

The Rites of Passage will put out heat like you never thought possible from an amplifier. I doubt the VTLs even come close despite the much higher power rating. It is not even that the Rites will run so much lower bias it is the damn heater on these tubes that draws a few amps...per tube. I have never felt a tube run so hot before or since.

Recently, I had a pair of Wall Audio M50 monoblocks that have 2 x 6C33C per channel as PSET making about 35 watts per mono. They also ran ruinously hot. Now the Ayon Crossfire, which makes almost the same power but runs much cooler because the heater filaments don't draw this ridiculous amount of power.

Not saying you shouldn't check them out but I am saying that you have not been prepared for that kind of heat before. It will be dissipation of over 1000 watts per monoblock.

I love this post...Morricab,you nailed it with regards to the heat problem.
Listening in one’s underwear,lmao...

At least Ron cannot say he wasn’t warned...

morricab · Oct 31, 2017

Ron Resnick said:
Thank you, but I have no doubt.

The Io is a combination phono stage and line stage. I have used the Io to drive directly the MB-750s for 18 years.

Great! I hope that you find a pair of Rites because they are probably one of the greatest sounding high power amps of all-time. Clartity and insight will be in abundance but with a rightness of timbre too. Rare birds for sure...

morricab · Oct 31, 2017

DaveyF said:
I love this post...Morricab,you nailed it with regards to the heat problem.
Listening in one’s underwear,lmao...

At least Ron cannot say he wasn’t warned...

Maybe listening in your underwear isn't so bad after all .

microstrip · Oct 31, 2017

Ron Resnick said:
Thank you, but I have no doubt.

The Io is a combination phono stage and line stage. I have used the Io to drive directly the MB-750s for 18 years.

The MB-750's have around 400kohm input impedance, as far as I remember the Pendragon crossover has 40 kohm input impedance.

Argonaut · Oct 31, 2017

morricab said:
Maybe listening in your underwear isn't so bad after all .

As long as they are not your wife's eh !

Atmasphere · Nov 1, 2017

microstrip said:
Heat is part of OTL's - they have to supply current and the large cathodes must be conveniently heated. Each 6C33 dissipates 41.5W just for filament! (A 6550 filament dissipates around 10W) .

This statement is misleading. The heat that the OTLs make is based on two things- tube type and class of operation.

We use 6AS7Gs in most of our amps (our Novacron was the first US product to use the 6C33 FWIW) and they run much cooler. A side advantage is that they also don't eat their sockets; the sockets for 6AS7Gs last for decades. If you place the amp in Standby you see how this is so; even after 12 hours of running the tubes are not hot- you can grab them with your hand, hang on and not get burned. This is not true of the 6C33 which is hot no matter what. With the 6AS7G, the heat comes from the class of operation; even if started stone cold, after only a minute of operation with B+ applied, the tubes become too hot to touch.

@Ron Resnick The MA-2 is a more reliable amplifier and a more transparent amplifier than the Rite of Passage (with similar power of 220 watts) and I know of a used and fully updated set (with a new warranty) if you are interested. The guy is selling them for less than a third of retail which makes them a pretty good deal. You won't find a Joule that has much of a warranty...

The big deal that you have to contend with is does either amp really work with your speakers.

microstrip · Nov 1, 2017

Atmasphere said:
This statement is misleading. The heat that the OTLs make is based on two things- tube type and class of operation. (...)

I owned the MA2's. IF I remember well they dissipated more than 650 watt per pair just for filaments. Even in standby they would heat my room. We must separate working temperature and power - I think these matters do not need the laws of thermodynamics to be fully understood.

And yes, they are great sounding amplifiers, extremely reliable. I only sold them because of heat, at that time I did not want to install an air conditioning system. I still keep the MP1, it is possible that one day I will return to MA2's - but I will want a mk3.3!

Atmasphere · Nov 1, 2017

For the power tubes that's 630 watts; for each tube its slightly less than 16 watts. Compare that to 50 watts of the 6C33, in nearly the same space and you can see that the 6C33
runs much hotter. So much hotter that it eventually damages the tube socket, which was never engineered to run such high filament currents. So any amp using 6C33s will need the sockets replaced sooner or later.

That amp I know of is updated to Mk3.3...

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Wanted: Joule Electra VZN-220 Rites of Passage

DaveyF

Well-Known Member

morricab

Well-Known Member

morricab

Well-Known Member

microstrip

VIP/Donor

Argonaut

Well-Known Member

Atmasphere

Industry Expert

microstrip

VIP/Donor

Atmasphere

Industry Expert

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