[carlman14]

I am digging the internal DAC mod. What DACdid you use? Or did you build it from a kit/scratch?

It was a fun mod for sure! I am using the khadas tone board. No DIY necessary. It's just a pre-built super tiny dac board with a nice DAC chip on it.

This is beautiful. What a nice product you've fashioned.

Do you get any USB interference from the USB-C or the DAC being so close to the electronics? If not, did you have to do any troubleshooting to help with that?

Really great job! I'm super jealous.

Thanks! So far, there hasn't been any kind of interference. Everything is incredibly quiet.

 

[Tom-s]

How are u doing, Tom?

I've had better day's! Here's why:


The Thomson 6080 is a personal favorite of mine. It's a clean, clear, airy, wonderful sounding tube that brought me a lot of joy! So I've recommended it to a few people.

Recently there's been various reports online (and offline) about the ones coming from sellers in Eastern Europe not functioning as they should.

Six of those found their way to me and i've had some fun with the testers today, checking them out.

They are supplied in HUGE boxes with some labels and a sticker on top. You could throw these of your local apartment building without anything happening to the tubes.

In the testers i couldn't detect any short or gas, so that's good. When required to supply any current at all, just about nothing happened.

In a transconductance tester where 7mA/V is the nominal NOS value, the best got up to 2mA/V.

Here's a picture of the line-up.



Luckily i had one good sample from my own collection to listen to!

Unfortunately, that one had sort of a bad interaction with my floor (hence, the bad day).



So it was dissected for the sake of curiosity.



Here's a view on one half:
- The coated heater wiring
- The cathode wherein the heater wiring lives
- The grid wire in nicely even spacing
- The anode plates with a large surface area for cooling
- All is suspended in a rigid mica construction seen on the previous image.



It's no Thomas Mayer picture quality (it's a phone!), but i hope you guys enjoyed it anyway!

 

[carlman14]

Recently there's been various reports online (and offline) about the ones coming from sellers in Eastern Europe not functioning as they should.

I can echo that statement. I ordered 3 of these tubes from a seller in Europe last year. All 3 were bad. Two were dead in one channel (one may have been dead in both channels, don't remember), and the other arc'd, blowing out my Atticus drivers. I haven't bothered with them since.

 

[cddc]

Recently there's been various reports online (and offline) about the ones coming from sellers in Eastern Europe not functioning as they should.

Six of those found their way to me and i've had some fun with the testers today, checking them out.

They are supplied in HUGE boxes with some labels and a sticker on top. You could throw these of your local apartment building without anything happening to the tubes.

In the testers i couldn't detect any short or gas, so that's good. When required to supply any current at all, just about nothing happened.

In a transconductance tester where 7mA/V is the nominal NOS value, the best got up to 2mA/V.

Here's a picture of the line-up.

Sorry to hear what happened to your working Thomson and those duds, Tom.

Just wondering where they got the new boxes for the duds? Those boxes look authentic, but why would they replace a NIB tube with a dud inside the box?

Also curious about the filament from your photo. The way how the filament is wound and how it is placed inside the cathode makes me wonder why a short is not happening? The filament is touching itself and the metal cathode in so many places. A short should have happened unless the filament is coated with insulating materials.

 

[cddc]

Will the frequent thermal expansion and contraction from the big changes in filament temperature peel away the insulating coating over time?

 

[wwmhf]

I've had better day's! Here's why:

Unfortunately, that one had sort of a bad interaction with my floor (hence, the bad day).



So it was dissected for the sake of curiosity.



Here's a view on one half:
- The coated heater wiring
- The cathode wherein the heater wiring lives
- The grid wire in nicely even spacing
- The anode plates with a large surface area for cooling
- All is suspended in a rigid mica construction seen on the previous image.



It's no Thomas Mayer picture quality (it's a phone!), but i hope you guys enjoyed it anyway!

Sorry for you loss, but now you and all of us know that this tube is well made

 

[attmci]

I can echo that statement. I ordered 3 of these tubes from a seller in Europe last year. All 3 were bad. Two were dead in one channel (one may have been dead in both channels, don't remember), and the other arc'd, blowing out my Atticus drivers. I haven't bothered with them since.

Wow, that's sad.

 

[carlman14]

Wow, that's sad.

Yeah I was pretty bummed for my Atticus. Luckily I was the original owner, so the driver replacement was free. That whole Thomson 6080 experience sucked though. It's amazing how many people are reporting receiving bad Thomson 6080s from Europe lately.

 

[raindownthunda]

I've had my crack for about a year and a half now, and I think I'm finally done upgrading (for now). Here's the final product:

• speedball
• stained/finished base
• film output caps
• film cap for last psu cap (with bypass)
• 24 step goldpoint attenuator with vishay dale resistors
• Schottky rectifier diodes
• choke
• integrated khadas tone board with usb-c input on the top panel (It's an all-in-one unit now!).
• toggle switch for switching between onboard dac and an external dac.

Very pleased with how this turned out.

The internal dac mod is genius! Really cool build

 

[headpfizer]

I just came into posession of a crack 1.1 With Speedball and Murdof Caps. It came with a selection of tubes. Can anyone recommend me some good combos from this list?

Power valves are:
Mullard 6080 SB CV 2984 KB/D made in England.
GEC valve made in uk, 6080 CV 2984 KB/Z.
Svetlana winged C NOS bottle shape, 6AS7G
Thomson CSF 6080WA ruggedised double power triode.
Philips ECG Jan 6080WC 3 mica.
Raytheon 6080.

Input valves are:
Vintage RCA NOS black plate Aug 1953, 12AU7
Mullard NOS CV4003 12AU7A
Jan Philips ECG 12AU7 5963
Electro Harmonix gold pins 12AU7/ECC82
JJ electronic ECC82 12AU7

Input valves with supplied 6SN7 to 12AU7 ADAPTER.
Tung Sol 6SN7 GTB.
Sylvania 6SN7 GTB
Electro Harmonix 6SN7GT.

 

[chrisdrop]

I just came into posession of a crack 1.1 With Speedball and Murdof Caps. It came with a selection of tubes. Can anyone recommend me some good combos from this list?

Power valves are:
Mullard 6080 SB CV 2984 KB/D made in England.
GEC valve made in uk, 6080 CV 2984 KB/Z.
Svetlana winged C NOS bottle shape, 6AS7G
Thomson CSF 6080WA ruggedised double power triode.
Philips ECG Jan 6080WC 3 mica.
Raytheon 6080.

Input valves are:
Vintage RCA NOS black plate Aug 1953, 12AU7
Mullard NOS CV4003 12AU7A
Jan Philips ECG 12AU7 5963
Electro Harmonix gold pins 12AU7/ECC82
JJ electronic ECC82 12AU7

Input valves with supplied 6SN7 to 12AU7 ADAPTER.
Tung Sol 6SN7 GTB.
Sylvania 6SN7 GTB
Electro Harmonix 6SN7GT.

GEC 6080
Sylvania 6SN7 GTB or Tung Sol 6SN7 GTB.

 

[JamieMcC]

Gec 6080 + Mullard 4003 would be my pick of the bunch 6sn7 should be great also.

Have fun

 

[carlman14]

Can anyone recommend me some good combos from this list

My vote also goes to the GEC 6080 + whatever. Great tube. If you haven't read the last page or two on this thread... I'd stay away from that Thomson 6080 if I were you.

 

[DenverW]

Hi all! Question for those of you that have installed a choke: how did you mount it? To the faceplate, or with standoffs? Did you do any extra ground wiring or just a simple replacement of one of the 270 5v?

I'm also waiting for some 100uf kzk white line film caps from russia...one month down and who knows how much more to wait?

 

[penguinofsleep2]

Assuming all of the above work, you hit the lottery on the power tubes. GEC is the obvious answer but side from it:

Thomson + Brimar is a great combo for a more "relax-fi" and easy listening sound without turning into mushy warm-poo. Given that the issues people had with the Thomson tubes have all been recent purchases, I'm guessing a bad/reject batch (or batch of dead tubes) got pulled out of a warehouse somewhere - but known good tubes are a good time.

Svetlana + Philips 12AU7 may also be a very good time. I have an unknown 12AU7 that looks to be of Philips construction + a black plate Svetlana - was may favorite combo excluding $$$ combos (such as GEC + w/e) given that I didn't want to chase down $$$ tubes for BH Crack (amp + mods + $$$ tubes = ~1k, there are amps better than the typical modded crack you can buy for 1k, including other BH stuff).