[Zachik]

I have the OTL on a shelf and, up until now, if I wanted to adjust the volume I had to stumble out of my comfortable chair. Serendipitously, I recently found a used Schiit Saga with a stepped attenuator (64 steps) and a REMOTE! Life is good! lol

You can always use the "GOTL Remote" for much less $$$...

 

[hpamdr]

I recently made a modest change to my system that really pleases me.

I have the OTL on a shelf and, up until now, if I wanted to adjust the volume I had to stumble out of my comfortable chair. Serendipitously, I recently found a used Schiit Saga with a stepped attenuator (64 steps) and a REMOTE! Life is good! lol

Personally, I do not have this issue as my dac(s) have remote to adjust output level and for sure it is very comfortable.
Just a question, do you use the saga in passive mode as i do not see any tube in the saga socket.

 

[gibosi]

Personally, I do not have this issue as my dac(s) have remote to adjust output level and for sure it is very comfortable.
Just a question, do you use the saga in passive mode as i do not see any tube in the saga socket.

Yes, I am using passive mode. I figure I have plenty of tube-goodness with the OTL and I don't need any more. But perhaps if I had a solid-state amp, it would be fun to roll tubes in the saga to add a little tube-flavor.

 

[chrisdrop]

Ferranti brand tubes. Anyone else have/seen/know anything about the brand?

 

[gibosi]

Ferranti brand tubes. Anyone else have/seen/know anything about the brand?

Ferranti was a British company, but I have not been able to find much information about it. I have a Ferranti 5U4G and it it looks (and sounds) different enough from other 5U4G that it doesn't appear to be a rebrand.

https://www.radiomuseum.org/dsp_hersteller_detail.cfm?company_id=6336

https://www.radiomuseum.org/r/ferranti_pegasus.html

 

[L0rdGwyn]

Ferranti brand tubes. Anyone else have/seen/know anything about the brand?

I can tell you from the construction that those are rebranded Mullard 6J5GT, made in the Tottenham, London factory after Philips / Mullard acquired what was left of British Tungsram in 1952. The spiked top mica is characteristic of Tungsram tubes, you can see it on other models.

 

[mordy]

Ferranti was a British company, but I have not been able to find much information about it. I have a Ferranti 5U4G and it it looks (and sounds) different enough from other 5U4G that it doesn't appear to be a rebrand.

https://www.radiomuseum.org/dsp_hersteller_detail.cfm?company_id=6336

https://www.radiomuseum.org/r/ferranti_pegasus.html

Found another source re the history of Ferranti:
https://mullard.org/blogs/our-product-manufacturers/ferranti
The company lasted over 100 years and tube production started in 1929. The main emphasis was on engineering, heavy equipment and defence contracts over the years. There is a note that after WW2 they started to supply tubes to other manufacturers. Manufacturer of TV sets from 1936 to 1957.
Ferranti was a developer of the first computers which used tubes.
One item listed for 1926 caught my attention LOL:
1926 Start of production of electric fires

 

[mordy]

You know those pictures on the internet - somebody taking a picture moments before the accident....
Here is such a picture:

Switched the voltage switch to 12V since I am now trying a 1962 Sylvania 12AU7 (branded Baldwin) supported by a small army of Foton 6H8S tubes - sounds very good. And look at that beautiful tube glow!
I usually leave the GOTL on for many hours; with fans it runs very cool. The amp played for an hour or so and I went outside for an errand and came back inside: Horror! A terrible room shaking hum!
Threw myself on the blue halo elevator power switch - the hum went away but it continued playing for a little while. Never a dull moment! What's going on????
Yanked out the adapter with the 12AU7 - could it be a bad adapter? Nothing smells burnt...
Switched back to 6.3V and put in a known working adapter w/ tube - everything is fine! Big sigh of relief....
But what happened? I have this box of tubes with the same pinout and using the same adapter:
12AX7, 12AU7, 12AT7, 12AZ7, 12BH7, E180CC (courtesy Phantaminum), 5693.
Let's see, 6SN7 is 6.3V, 12SN7 is 12.6V - let's check these tubes:
Why in the world would a 12AU7 be 6.3V and all the 12s listed are 12.6V??? (The only other tube listed above that is not 12V is the E180CC).
So the nice tube glow came from a tube struggling with a tube-lethal dose of voltage....
Luckily I have a spare.
All is well again.
Did I mention that it sounds very good?

 

[gibosi]

You know those pictures on the internet - somebody taking a picture moments before the accident....
Here is such a picture:

Switched the voltage switch to 12V since I am now trying a 1962 Sylvania 12AU7 (branded Baldwin) supported by a small army of Foton 6H8S tubes - sounds very good. And look at that beautiful tube glow!
I usually leave the GOTL on for many hours; with fans it runs very cool. The amp played for an hour or so and I went outside for an errand and came back inside: Horror! A terrible room shaking hum!
Threw myself on the blue halo elevator power switch - the hum went away but it continued playing for a little while. Never a dull moment! What's going on????
Yanked out the adapter with the 12AU7 - could it be a bad adapter? Nothing smells burnt...
Switched back to 6.3V and put in a known working adapter w/ tube - everything is fine! Big sigh of relief....
But what happened? I have this box of tubes with the same pinout and using the same adapter:
12AX7, 12AU7, 12AT7, 12AZ7, 12BH7, E180CC (courtesy Phantaminum), 5693.
Let's see, 6SN7 is 6.3V, 12SN7 is 12.6V - let's check these tubes:
Why in the world would a 12AU7 be 6.3V and all the 12s listed are 12.6V??? (The only other tube listed above that is not 12V is the E180CC).
So the nice tube glow came from a tube struggling with a tube-lethal dose of voltage....
Luckily I have a spare.
All is well again.
Did I mention that it sounds very good?

I'm not sure I precisely understand what happened here...

But I think I will take this opportunity to remind folks that 12A-7 tubes can be configured to run as 6-volt or 12-volt tubes, depending on how the heaters are connected. And if the adapter is 12A-7 to 6SN7, then the heaters will be configured to operate in 6-volt circuits. But if the adapter is 12A-7 to 12SN7, the heaters will be configured to operate in 12-volt circuits.

Also, both the E180CC and the E80CC have the same pinout as the 12A-7s, and thus they too can be configured to operate in either 6-volt or 12-volt circuits.

Be careful out there.

 

[mordy]

I realized too late that the adapter was wired for 6.3V and unfortunately used it with 12.6V.

 

[triod750]

And your music is on fire...

 

[L0rdGwyn]

I am reposting my GOTL GIF for no reason other than I just remembered it. Some day I will do something with all of those OTL power tubes.

Are you working on any amplifiers right now, @2359glenn ?

 

[mordy]

And your music is on fire...

No smoke, no fire - just a horrendous HUMMMMMMMMM
The funny thing is that the amp continued to play after I shut it off (capacitors have to discharge) so I sort of knew that it must be the tube and not the amp.

 

[triod750]

No smoke, no fire - just a horrendous HUMMMMMMMMM
The funny thing is that the amp continued to play after I shut it off (capacitors have to discharge) so I sort of knew that it must be the tube and not the amp.

I thought your musicians always were on fire...

 

[maxpudding]

Tube gone bad? luckily nothing exploded.