Sounds like you listen to music with your left brain, try the right brain (pun intended.)
Music is art and perception/consciousness can't be modeled or measured, or analylized as having "errors". 1-on, 0- off, 1+1=2 are abstractions that form the basis of math, neither can be proven. No EE or physicist can describe a square wave without using the 1/0= infinity leap of faith. Do square waves exist? Well I guess the physicist who posted here earlier would say they did during the "big bang". Its all theory, none of it correct, if it were then physics would have a model of the universe that could explain gravity and meaningless abstractions like black holes and big bangs. We don't have all the answers especially when it comes to the brain, consciousness, and art. Perception is as much a "singularity" as a black hole.
When the goal is listening to music (art), and you are an engineer type (myself included) you have to let the right brain take over, those errors you speak of the brain makes when listening, are the magic that make music and life liveable. Science is a tool not a belief system. Measurements of EMF or if you prefer newtonian electrons across an amplifier output with a nice 2-D FFT are useful tools, but ultimately music is art and aesthetics.
So if that $1k GZ34 helps someones right brain kick in when listening to his Bach, good for him.
Hi!
Agree! When someone is getting happiness with expensive rectifiers, then go for it. But your post is in no way a good argument pro or con expensive rectifiers.
In my experience a properly designed amp which is not dependant on specific recitifiers to sound good will please the right half of the brain even more.
BTW I'm in no way against good rectifiers. They just don't need to be expensive. The best rectifiers out there can be had for a dollar each!
For example this one:
http://vinylsavor.blogspot.co.at/2012/06/tube-of-month-6dq4.html
Thomas
Agree! When someone is getting happiness with expensive rectifiers, then go for it. But your post is in no way a good argument pro or con expensive rectifiers.
In my experience a properly designed amp which is not dependant on specific recitifiers to sound good will please the right half of the brain even more.
BTW I'm in no way against good rectifiers. They just don't need to be expensive. The best rectifiers out there can be had for a dollar each!
For example this one:
http://vinylsavor.blogspot.co.at/2012/06/tube-of-month-6dq4.html
Thomas
Thomas, the big issue at hand is for people restoring old audio equipment which was designed for the GZ34.
I have one such stereo, the Monarch STA-400 which uses the GZ34 and as such it is not possible to convert it to 6DQ4.
So my options are basically (1) use new manufacture tubes which appear to be of lesser quality, (2) pay the overblown price original tubes are going for, (3) keep trying on bid sites in the hope I will eventually get a tube at a reasonable price, (4) convert to SS rectification with ballast resistors to try to compensate for tube voltage drop.
For now the amp sets with a box of parts I am collecting for the day when I can restore it.
I have one such stereo, the Monarch STA-400 which uses the GZ34 and as such it is not possible to convert it to 6DQ4.
So my options are basically (1) use new manufacture tubes which appear to be of lesser quality, (2) pay the overblown price original tubes are going for, (3) keep trying on bid sites in the hope I will eventually get a tube at a reasonable price, (4) convert to SS rectification with ballast resistors to try to compensate for tube voltage drop.
For now the amp sets with a box of parts I am collecting for the day when I can restore it.
Hi!
Yes, of course I understand. And you probably don't want to mess around with old equipment but leave it as close to the original state as possible.
Thomas
Yes, of course I understand. And you probably don't want to mess around with old equipment but leave it as close to the original state as possible.
Thomas
Sounds like you listen to music with your left brain, try the right brain (pun intended.)
I'm a jazz musician, and I'm pretty right brained!! That's not the issue, I love my music. But I'm a psychologist, and also I've been through a lot of treatment for tinnitus. That kind of treatment makes you realise how important the brain is in processing and interpreting date from our sense organs. The volume of tinnitus actually seems to go up and down according to how you interpret it. That's just one example - there are a huge number of others. Have you seen those trick videos where a gorilla walks across he screen and you don't see it?
Missing the gorilla: Why we don't see what's right in front of our eyes
The brain has only a finite ability to process signals. The processing power of the brain has been estimated as 126 bits per second (Miller, 1956). I don't know if anyone can update this reference. Anyway, the point I was making is that while our senses can pick up very small differences, our brain still has to process the information.
andy
Not really when compared to other land mammals. Frequency Hearing Ranges in Dogs and Other Species
Brainwave scanner can measure and show the differences when occurs in our brain. Those graphic differences can be interpreted / analyzed.
Seems to be quite difficult to establish how fast we process information, but there is this:
information theory (mathematics) : Physiology -- Britannica Online Encyclopedia
"The table Information transmission rates of the senses (eyes 10 million, skin 1 million, ears 100,000 bits per second etc.) shows how much information is processed by each of the five senses. This table immediately directs attention to the problem of determining what is happening to all this data. In other words, the human body sends 11 million bits per second to the brain for processing, yet the conscious mind seems to be able to process only 50 bits per second."
Seems like we may hear lots of things, but we don't necessarily know or recognise what we are hearing. We may have golden ears but we have very fallible processors stuck on the ends of them. It's easy to believe that one person "hears" one thing and another person "hears" something else, or more correctly processes the incoming information differently.
andy
information theory (mathematics) : Physiology -- Britannica Online Encyclopedia
"The table Information transmission rates of the senses (eyes 10 million, skin 1 million, ears 100,000 bits per second etc.) shows how much information is processed by each of the five senses. This table immediately directs attention to the problem of determining what is happening to all this data. In other words, the human body sends 11 million bits per second to the brain for processing, yet the conscious mind seems to be able to process only 50 bits per second."
Seems like we may hear lots of things, but we don't necessarily know or recognise what we are hearing. We may have golden ears but we have very fallible processors stuck on the ends of them. It's easy to believe that one person "hears" one thing and another person "hears" something else, or more correctly processes the incoming information differently.
andy
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Why not just do this , post #34. You still keep it with the benefits of the slow warmup. Low cost, will last and NOS preserved longer! Nice on vintage amps to keep the same tube too!
http://www.diyaudio.com/forums/tubes-valves/214534-why-gz34-rectifiers-so-expensive-4.html
Randy
http://www.diyaudio.com/forums/tubes-valves/214534-why-gz34-rectifiers-so-expensive-4.html
Randy
Attachments
Your B+ goes up by the voltage drop of the GZ34 (only 15 or so volts for GZ34).
SS diode characteristics are different than tubes, faster turn on, turn on at higher peak with greater current draw vs the tube with a greater voltage drop. This impacts power supply ripple.
1N4007s are noisy, but UF4007 would be quieter. Or you can add snubbers.
If I were to do that, I'd use a octal plug and build a module to replace the tube without modifying the chassis. Thus if I ever found a reasonably priced NOS GZ34 I could swap it out.
a 60R 3W resistor in series with the diodes might drop the 15V, but I suspect the dynamic resistance of the GZ34 is lower and so there would be more sag in the B+ supply with the SS/Resistor combo.
Hmmm. Just looked at the curve for the 5AR4 and at 225mA the dv/di is 1V/25mA for a dynamic impedance of 40 Ohms, so the SS/R combo would have more voltage sag.
SS diode characteristics are different than tubes, faster turn on, turn on at higher peak with greater current draw vs the tube with a greater voltage drop. This impacts power supply ripple.
1N4007s are noisy, but UF4007 would be quieter. Or you can add snubbers.
If I were to do that, I'd use a octal plug and build a module to replace the tube without modifying the chassis. Thus if I ever found a reasonably priced NOS GZ34 I could swap it out.
a 60R 3W resistor in series with the diodes might drop the 15V, but I suspect the dynamic resistance of the GZ34 is lower and so there would be more sag in the B+ supply with the SS/Resistor combo.
Hmmm. Just looked at the curve for the 5AR4 and at 225mA the dv/di is 1V/25mA for a dynamic impedance of 40 Ohms, so the SS/R combo would have more voltage sag.
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The tube still works as intended and you don't get any change in voltage. It takes a fair amount of the load off the tube in so helping high load situations (bigger amps). If the power flashes off and on in a failure or accident that can help expensive NOS too.
You don't have to put the diodes on the spare pins as in the drawing I found. Just put them on the leads to the tube and put good shrink wrap over them.
Nobody will know they are there!
Randy
You don't have to put the diodes on the spare pins as in the drawing I found. Just put them on the leads to the tube and put good shrink wrap over them.
Nobody will know they are there!
Randy
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No, there is not a slow start-up with 1N4007.
If you must use silicon diodes, then a single TV damper diode in series could be used for slow start-up though.
The added series diodes do not actually take load off the tube. Since it is a series circuit the current through the tube is still the same and the VI curve of the tube rectifier still dominates in the forward (conducting) state so the tube rectifier characteristics are retained.
What happens is that the diodes dominate in the reverse direction removing the PIV stress on the tube rectifier. This will often stop a tube arc from starting, or kill the arc before the tube blows up. A tube won't arc over when it is conducting since the voltage across it is small. If the forward current is concentrated in a small area due to poor tube quality, creating a local hot spot, that's where the arc will start when the polarity reverses and there is 800 volts across the gap.
I have tested the diode mod several times and it will even save a tube that has already arcced over and become useless. it works so well that I added the mod to the new SSE boards since that design runs the rectifier near it's spec limit and has blown a few new production 5AR4's.
I've been using the diode in series with the plate approach on 5AR4 since the late 1990s, and can confirm it really prevents a lot of trouble for the reasons tubelab explained in the previous post.
I use them also in applications with 5U4 when the tube is used at voltages close to its rated maximums.
I use them also in applications with 5U4 when the tube is used at voltages close to its rated maximums.
It seems it is only the metal base GZ34 that are expensive, I have seen NOS Bakelite base units go very cheap, I have about 5 NOS Bakelite sitting in my boxes somewhere......
From what I've watched the Bakelite base units go $40- $50.
Six bids up to 12.50 plus $7 shipping with 6 days to go? But this is two tubes.
GZ34/5AR5 (2) MULLARD (BRANDED BOGEN) USED TESTED MATCHED VACUUM TUBES (E38) | eBay
Single tube at $12.5 plus $10 s/h with 6 bids and 9 days to go with 6 bidders.
1 5AR4-GZ34 VACUUM TUBE MADE IN GREAT BRITAIN TESTS EXCELLENT NOS (1 of 3) | eBay
My Idea of reasonable is less than $20 including shipping.
Compared to 5U4s which start around $5 the GZ34 sells for stupid prices.
Six bids up to 12.50 plus $7 shipping with 6 days to go? But this is two tubes.
GZ34/5AR5 (2) MULLARD (BRANDED BOGEN) USED TESTED MATCHED VACUUM TUBES (E38) | eBay
Single tube at $12.5 plus $10 s/h with 6 bids and 9 days to go with 6 bidders.
1 5AR4-GZ34 VACUUM TUBE MADE IN GREAT BRITAIN TESTS EXCELLENT NOS (1 of 3) | eBay
My Idea of reasonable is less than $20 including shipping.
Compared to 5U4s which start around $5 the GZ34 sells for stupid prices.
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