[Xcalibur255]

@Dubstep Girl's rectifier thread is one of the great contributions in head-fi history IMHO, whether you agree with the notes or not, it's a great resource for those getting involved in swapping those rectifier's!

Gel3n came in yesterday - it's fabulous. Some pics and more later. Been having fun swapping out those rectifiers.

I respect the effort that was put into it, but I still feel that article was misleading for a lot of people. The results of that testing are only valid for the amp she was using to do the listening/testing IMO. It would have been better to post it in the owners thread for that amp where it would be directly applicable and helpful, rather than apply the impressions generically to the rectifiers themselves.

 

[mordy]

Hi X255,
It seems to me that the metal casing on the C3g tubes has a function; maybe similar to the black coating inside the glass on the TS BGRP tubes - shielding against RF interference?
I have also come to the realization that the same tube may sound different in different amps. And then synergy with other tubes is very important.
I still would like to think that a certain select group of tubes has the potential to sound good across the board in all amps...

 

[Phantaminum]

Which model of Syl 12SN7?

Now that you have c3g fresh in mind....compare to Syl 6SN7W...

I am staying with 6x 6BX7 and British made Mazda ECC804 (little dual C3g...) tonight and:



I know, I know...there are MORE than 3 musicians.....

I am digging the HD580's w/aftermarket silver cable...more midrange tha HD650's...

Hey JV,

It’s a Sylvania chrome top, getter flash doesn’t extend to the bottom, green label with a vertical date 12sn7. With the HD650s and four Chatham 6as7gs it gives it extension on both ends while having great mids.

I think I got them pretty cheap. Here’s an eBay listing of exactly what they look like:
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/192633558766

Comparing both the c3g to the Sylvania 6SN7W is a bit harder. I’ll keep try to keep it simple and as a mesurement stick I lean towards a lush sound.

With that said, I enjoy the HD650 with the c3g compared to the 6sn7w. The Siemens is tighter, a tad bit faster, and more forceful. The 6sn7w is not as forceful but has a slightly larger sound stage (it’s a HD650) and leaner. The c3g bring some type of magic in this combination. It feels like the headphones are removed and you just get music.

With the Auteurs I enjoy the 6sn7w with a sixtet of 6bx7s. Just sounds very natural and smooth. The c3gs still sound great but the 6sn7w has even greater synergy with these headphones. Huge sound stage with the Auteurs, smooth/liquid, and same detail as the c3g. I can turn up the volume more in this combination.

I love the Sylvania but the Siemens really surprised me.

 

[2359glenn]

Hey JV,

It’s a Sylvania chrome top, getter flash doesn’t extend to the bottom, green label with a vertical date 12sn7. With the HD650s and four Chatham 6as7gs it gives it extension on both ends while having great mids.

I think I got them pretty cheap. Here’s an eBay listing of exactly what they look like:
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/192633558766

Comparing both the c3g to the Sylvania 6SN7W is a bit harder. I’ll keep try to keep it simple and as a mesurement stick I lean towards a lush sound.

With that said, I enjoy the HD650 with the c3g compared to the 6sn7w. The Siemens is tighter, a tad bit faster, and more forceful. The 6sn7w is not as forceful but has a slightly larger sound stage (it’s a HD650) and leaner. The c3g bring some type of magic in this combination. It feels like the headphones are removed and you just get music.

With the Auteurs I enjoy the 6sn7w with a sixtet of 6bx7s. Just sounds very natural and smooth. The c3gs still sound great but the 6sn7w has even greater synergy with these headphones. Huge sound stage with the Auteurs, smooth/liquid, and same detail as the c3g. I can turn up the volume more in this combination.

I love the Sylvania but the Siemens really surprised me.

I was listening to your amp with Auteurs driven by six 6BX7 and a 13D1. I don't have a 6SN7W
Sounded great to me!

 

[Phantaminum]

I was listening to your amp with Auteurs driven by six 6BX7 and a 13D1. I don't have a 6SN7W
Sounded great to me!

That’s another great combination. I’ve enjoyed the Auteurs with the 6sn7ws, the 13D1, and the Osram B63. All great sounding tubes.

With the HD650 the c3g really just wow me.

 

[mordy]

Hey JV,

It’s a Sylvania chrome top, getter flash doesn’t extend to the bottom, green label with a vertical date 12sn7. With the HD650s and four Chatham 6as7gs it gives it extension on both ends while having great mids.

I think I got them pretty cheap. Here’s an eBay listing of exactly what they look like:
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/192633558766

Comparing both the c3g to the Sylvania 6SN7W is a bit harder. I’ll keep try to keep it simple and as a mesurement stick I lean towards a lush sound.

With that said, I enjoy the HD650 with the c3g compared to the 6sn7w. The Siemens is tighter, a tad bit faster, and more forceful. The 6sn7w is not as forceful but has a slightly larger sound stage (it’s a HD650) and leaner. The c3g bring some type of magic in this combination. It feels like the headphones are removed and you just get music.

With the Auteurs I enjoy the 6sn7w with a sixtet of 6bx7s. Just sounds very natural and smooth. The c3gs still sound great but the 6sn7w has even greater synergy with these headphones. Huge sound stage with the Auteurs, smooth/liquid, and same detail as the c3g. I can turn up the volume more in this combination.

I love the Sylvania but the Siemens really surprised me.

Hi P,
I think that I have the same tube, but labeled Honeywell. The number 312 indicates Sylvania, and this tube was made in 1957:

And as a rebranded tube it fetches a lower price.

 

[Phantaminum]

Hi P,
I think that I have the same tube, but labeled Honeywell. The number 312 indicates Sylvania, and this tube was made in 1957:

And as a rebranded tube it fetches a lower price.

Hey Mordy,

Looks like the same tube. There’s is also the Sylvania 6sn7gtb/12sn7gtb that look exactly like the GT versions.

Like these:
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/123224250887

Maybe @gibosi can tell us how to tell a difference? They look the same to my eyes.

 

[UntilThen]

I think I got them pretty cheap. Here’s an eBay listing of exactly what they look like:
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/192633558766

I was going to buy these but then I ask myself, ‘Don’t I have enough drivers already?’

My amp is on my screen. Going interstate for a few days. Will miss my head-fi.

 

[myphone]

Hey Mordy,

Looks like the same tube. There’s is also the Sylvania 6sn7gtb/12sn7gtb that look exactly like the GT versions.

Like these:
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/123224250887

Maybe @gibosi can tell us how to tell a difference? They look the same to my eyes.

These are later year GT/GTA/GTB tubes. There are 5 holes. Earlier ones have either 2 holes or 3 holes (1952, badboy).

 

[mordy]

These are later year GT/GTA/GTB tubes. There are 5 holes. Earlier ones have either 2 holes or 3 holes (1952, badboy).

The GT, GTA and GTB all are slightly different in their electrical characteristics but the audible difference may be very small between the GTA and GTB, if any.
The GT was the earliest version and some people prefer those. Older is better - no?

 

[Phantaminum]

These are later year GT/GTA/GTB tubes. There are 5 holes. Earlier ones have either 2 holes or 3 holes (1952, badboy).

For rebrands how do you tell if they are GTs or GTA/Bs? I also thought the Bad Boys had the flash getter at the bottom of the tube?

 

[myphone]

For rebrands how do you tell if they are GTs or GTA/Bs? I also thought the Bad Boys had the flash getter at the bottom of the tube?

Yes, early GTs/VT231 (before 1953) have bottom getter, including bad boy. The only early top getter tubes i have seen are W's (6SN7W or 6SN7WGT).

There are two types of GTAs (3 holes and 5 holes). I have not seen 3 hole GTB yet.

 

[mordy]

Yes, early GTs (VT231) have bottom getter, including bad boy. The only early top getter tubes i have seen are W's (6SN7W or 6SN7WGT)

For rebrands how do you tell if they are GTs or GTA/Bs? I also thought the Bad Boys had the flash getter at the bottom of the tube?

Normally Sylvania tubes have markings on the top of tube and here you can see which revision it is. My tube (pictured above) says GT. It may also say on the glass. Sometimes the print is very faint and you have to hold the tube at different angles and in different light to be able to read the markings.

 

[gibosi]

Hey Mordy,

Looks like the same tube. There’s is also the Sylvania 6sn7gtb/12sn7gtb that look exactly like the GT versions.

Like these:
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/123224250887

Maybe @gibosi can tell us how to tell a difference? They look the same to my eyes.

In 1954, Sylvania introduced their 6SN7GTA with ribbed obliquely oriented plates and a wafer stem. The earlier GT had "t"-plates, with two or three rivet holes, oriented parallel, and a flat pressed glass stem. The new, more compact GTA design was said to be less microphonic and able to accommodate larger peak plate voltages with better heat dissipation. And finally, the GT has a rectangular top mica with teeth, whereas, the GTA has an oversize round top mica with teeth

To the best of my knowledge, there are no easy to see construction differences between the GTA and the later GTB, when it was first introduced.

 

[UntilThen]

Don’t forget to get some el cheapo Sylvania 7n7.