hodgjy
Headphoneus Supremus
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The EZ80 is a full wave rectifier that is popular in several tube amps, including the Woo Audio WA2 and Trafomatic Head One. I have some experience tube rolling them and I wanted to share some of my findings here.
There are two schools of thoughts when it comes to tube rectifiers:
As I describe each type of EZ80, I stress the sonic differences between them are slight. Rolling different ones in won't radically change the sound of your amp, but they can be used to fine tune the desired sound. Again, subtle differences.
Another thing to consider, many of the different "brands" are made in the same plant or in plants owned by the same parent company using uniform standards and tools. That's why I focus more on plate types than the name printed on the glass itself.
The plate types I've come across are described below. For the record, I'm only describing NOS and state nothing about new production as I haven't heard any and I have no desire to ever use new production EZ80s.
Type A: the "Philips" Type
This is the most common plate arrangement among the EZ80. It was two perpendicular plates that intersect and run the full length of the glass, as seen below:
This type is found in Philips, Miniwatt, Amperex, La Radiotechnique, Brimer, Mullard, GE, Valvo, Ei (which bought Philips tools), RSD, and several others. Telefunken generally follows this pattern, but slight variations exist. I haven't used a Telefunken, so I can't personally comment on its sound. As I stated above, many of these brand names are made in the same physical plant, so differences in sound are expected to small.
Below you can see various brands in my personal collection that follow the Philips type:
General sonic characteristics are:
This is a little more on the rare side, and it's become more rare now considering the word is out and it's no longer a hidden gem. However, they can be purchased on eBay if you're willing to deal with international mail.
This has two smaller, perpendicular plates that don't run the full length of the tube, as the Philips type does. Below is an example from my collection:
General sonic characteristics are:
These are dirt cheap and easily found. Their plates run the full length of the tube, but the connect at the tube margins to form a "T" as you can see below from two tubes in m collection:
General sonic characteristics are:
Based on my experiences, rolling the EZ80 does make subtle changes to the overall sound. However, it won't radically change or re-invent the sound profile. Again, the differences are very small. Untrained ears probably wouldn't be able to hear the differences.
So, which one should you get?
The easy answer is several, as many of them are inexpensive and easy to get, so you make up your own mind. However, I would avoid paying over $40 US for any single tube because good sounding tubes can be had for that price or lower. In other words, don't go spending $100 for a black plate Brimer when a $25 GE sounds just as good. In fact, chances are they were made in the plant with the same tools.
But, if you made me pick a single tube, here is my ranking, in order from best to less:
There are two schools of thoughts when it comes to tube rectifiers:
- No effect on sound (Jack Wu says the effect is minimal in the Woo Audio WA2, for example).
- Noticeable effect on sound (users of the WA2, for example).
- Small effect on sound.
- Large effect on sound.
- The EZ80 does affect sound, but the differences are small.
- There is more variation within each brand/make/model of the same tube than there are between brand/make/model of different tubes. I attribute this to tube age, condition, and manufacturing variance. In other words, there may be some ability to identify a "house sound" of each type of EZ80, but individual variances within each tube may make it more difficult to broadly apply such an interpretation. I think this is why so many opinions exist on the sound of the EZ80. For example, someone might say the Mullard EZ80 is boring but someone else says it is extremely lively.
As I describe each type of EZ80, I stress the sonic differences between them are slight. Rolling different ones in won't radically change the sound of your amp, but they can be used to fine tune the desired sound. Again, subtle differences.
Another thing to consider, many of the different "brands" are made in the same plant or in plants owned by the same parent company using uniform standards and tools. That's why I focus more on plate types than the name printed on the glass itself.
The plate types I've come across are described below. For the record, I'm only describing NOS and state nothing about new production as I haven't heard any and I have no desire to ever use new production EZ80s.
Type A: the "Philips" Type
This is the most common plate arrangement among the EZ80. It was two perpendicular plates that intersect and run the full length of the glass, as seen below:
This type is found in Philips, Miniwatt, Amperex, La Radiotechnique, Brimer, Mullard, GE, Valvo, Ei (which bought Philips tools), RSD, and several others. Telefunken generally follows this pattern, but slight variations exist. I haven't used a Telefunken, so I can't personally comment on its sound. As I stated above, many of these brand names are made in the same physical plant, so differences in sound are expected to small.
Below you can see various brands in my personal collection that follow the Philips type:
General sonic characteristics are:
- Ever so slightly rolled off high and low ends.
- A tough of warmth to midrange. A little bit of liquidity.
- Voices are clear, but are a touch subdued.
This is a little more on the rare side, and it's become more rare now considering the word is out and it's no longer a hidden gem. However, they can be purchased on eBay if you're willing to deal with international mail.
This has two smaller, perpendicular plates that don't run the full length of the tube, as the Philips type does. Below is an example from my collection:
General sonic characteristics are:
- Most linear of all the EZ80s.
- Tight, deep bass and extended highs, but never bright.
- Voices come to the forefront and are very clear.
- There is more space around the notes, which contributes to the eccentuation of voices, clear treble, and tight bass.
- Not a lot of warmth there. You can feel the tube magic, but it's definitely solid state sounding.
- It's the best EZ80 I've heard.
These are dirt cheap and easily found. Their plates run the full length of the tube, but the connect at the tube margins to form a "T" as you can see below from two tubes in m collection:
General sonic characteristics are:
- Ever so slightly rolled off high and low ends.
- The warmest of the bunch.
- Voices not as out front as the RFT.
Based on my experiences, rolling the EZ80 does make subtle changes to the overall sound. However, it won't radically change or re-invent the sound profile. Again, the differences are very small. Untrained ears probably wouldn't be able to hear the differences.
So, which one should you get?
The easy answer is several, as many of them are inexpensive and easy to get, so you make up your own mind. However, I would avoid paying over $40 US for any single tube because good sounding tubes can be had for that price or lower. In other words, don't go spending $100 for a black plate Brimer when a $25 GE sounds just as good. In fact, chances are they were made in the plant with the same tools.
But, if you made me pick a single tube, here is my ranking, in order from best to less:
- RFT Type
- Philips Type
- Tesla Type
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