Tube Rolling w/Crack

[Tom-s]

I'm with attmci,

What are the power transformer specs for Crack 1.1 and Crack a two?

Interested in those to try more tube rolling !

Edit: Hoping for 5A + heater supplies!

[Paul Birkeland]

The beefy heater winding on the C2A is a 5A winding.  It, however, powers both the 6080 and the 12AU7.  You can heat the 12AU7 off the winding that heats the 6AQ5's, but that's all the power that winding has to give.  Having done that modification, you can then draw 5A off the 6080's winding.

Do note that none of this takes into account that when you plug in some different twin triode regulator, you may end up needing to redesign the circuit for it to work properly, and this can be a lot of work. 

The Crack power transformer won't support any of this business. 

[attmci]

The beefy heater winding on the C2A is a 5A winding.  It, however, powers both the 6080 and the 12AU7.  You can heat the 12AU7 off the winding that heats the 6AQ5's, but that's all the power that winding has to give.  Having done that modification, you can then draw 5A off the 6080's winding.

Do note that none of this takes into account that when you plug in some different twin triode regulator, you may end up needing to redesign the circuit for it to work properly, and this can be a lot of work. 

The Crack power transformer won't support any of this business.

Many thanks, Paul. So the Crack 1.1 use the same larger transformer? That's great news.

[Chris65]

So the Crack 1.1 use the same larger transformer? That's great news.

Don't think so, the Crack 1.1 uses a smaller transformer than the PT-8 used in the Crack-a-two-a.
PB said: "The Crack power transformer won't support any of this business."

[Paul Birkeland]

Many thanks, Paul. So the Crack 1.1 use the same larger transformer? That's great news.

No, as I said before, the Crack won't support what you're trying to do.  The Crack-a-two-a power transformer is physically larger and electrically more potent than the transformer in the Crack.

[Tom-s]

If anyone in Europe is looking for the perfect tube. Really, try an ECC40. It's cheap (vs ECC82), readily available.

Why i wanted to try them in Crack: http://kolbrek.hoyttalerdesign.no/index.php/tubes/distortion-in-small-signal-tubes

Is operates perfectly in a normal Crack with Speedball. It helps to install the E80CC switch mod (470 Ohm R1) and get the most out of this tube.

Try the Holland made (Sittard/Eindhoven) ECC40 tubes for the E80CC (pinched waist) sound that came from the Dutch factories (Heerlen/Eindhoven).

The Hamburg version is more lush, with the same detail retrieval but more weight in the midrange.

The Tungsram versions are on their own really. They could be compared best tot the Tungsram E80CC in terms of sound.

They are a step-up from the 12au7 and a side step to the E80CC (I like most ECC40's better, different soundstage, smaller, more detailed, ECC40's gives a different/more weight to instruments).

Buy an 9 hole to -> 8 hole rim lock adapter via ebay or your local supplier or DIY (i bought one for 10€).

I've been using these for 2-3 months now with great results. My collection is over 15 and growing (collecting one from every year 1948 -> 1957 from the Dutch factories).


Edit: Tube data: http://www.r-type.org/pdfs/ecc40.pdf

[attmci]

If anyone in Europe is looking for the perfect tube. Really, try an ECC40. It's cheap (vs ECC82), readily available.

Why i wanted to try them in Crack: http://kolbrek.hoyttalerdesign.no/index.php/tubes/distortion-in-small-signal-tubes

Is operates perfectly in a normal Crack with Speedball. It helps to install the E80CC switch mod (470 Ohm R1) and get the most out of this tube.

Try the Holland made (Sittard/Eindhoven) ECC40 tubes for the E80CC (pinched waist) sound that came from the Dutch factories (Heerlen/Eindhoven).

The Hamburg version is more lush, with the same detail retrieval but more weight in the midrange.

The Tungsram versions are on their own really. They could be compared best tot the Tungsram E80CC in terms of sound.

They are a step-up from the 12au7 and a side step to the E80CC (I like most ECC40's better, different soundstage, smaller, more detailed, ECC40's gives a different/more weight to instruments).

Buy an 9 hole to -> 8 hole rim lock adapter via ebay or your local supplier or DIY (i bought one for 10€).

I've been using these for 2-3 months now with great results. My collection is over 15 and growing (collecting one from every year 1948 -> 1957 from the Dutch factories).


Edit: Tube data: http://www.r-type.org/pdfs/ecc40.pdf

Thanks for sharing.

Don't you think the heat current of the ecc40 doubles that of a 12au7?  Though same as an e80cc.

We have to keep in mind that The PT-3 can only handle 3.5 amps RMS. So there is not much room here.

[Tom-s]

Yes the heater current is 0.6A like 6SN7, E80CC, 12BH7, 7119 and lot's of others you can use in Crack.
It's perfectly fine in Crack.  With 0.4-0.5A (6080 or 5998) to spare the transformer is happy with these.
If using 2x 6BL7 (2x 1.5A) as a power tube beware only to use 0.3A tubes.

[attmci]

Yes the heater current is 0.6A like 6SN7, E80CC, 12BH7, 7119 and lot's of others you can use in Crack.
It's perfectly fine in Crack.  With 0.4-0.5A (6080 or 5998) to spare the transformer is happy with these.
If using 2x 6BL7 (2x 1.5A) as a power tube beware only to use 0.3A tubes. TRUE!

[kritpoon]

Please nare with me, I just got the Telefuken 12au7 and thought would do my first excercise for comparison. Please bear with me. Note: this is only aubjective using my limited knowledge of audio jargon and proper evaluation method.


Telefuken 12au7 (Smooth Plate) vs Mullard 12au7 (short Plate) 1961 with RCA 6as7g Black Plate

Amp: Stock Crack w/ Speed Ball
Cans: Hd-580 with Furutech Cable
Digital: Arcam iRdac
USB Cable: Tchernov USB-C
RCA: Cardas Golden Cross

TELEFUKEN 12AU7 SMOOTH PLATE
High -very open airy sound, extended, crisp but not harsh, some what a little bright for my taste

Mid- compare to mallard its a bit thin, but comparing to the tube itself the whole spectrum, I feels that its in balance with the high and bass.

Low-mid bass sounds good and punchy-snappy (quite dynamic), but loss to the Mullard on the lower bass oomph. and decay of the note.

Sound stage - Wider than the mullard, the instrument separation is better

Smoothness - Quite smooth sounding tube, sounds coherent. transition of top to mid to bottom is very well connected.

Mullard 12AU7 Boxed PLATE

High -a tiny bit roll off, analog like sound. Think smooth, lush, soft top end.

Mid- This is where the magic happen. The mid is forward, warm and very very smooth. Think 35 years old Scotch Whisky smooth.

Low- Mid bass control is lacking, but the lower bass sound very nice with the oomph extended. Not as dynamic as the Telefunken. But I like this fat oomph note.

Sound stage - More intimate, the soundstage width is narrower than the Telefuken, but still very good. The separation can be better, but not bad.

Smoothness - This is one very smooth, I mean silky smooth. tube and very analog like sound (Think LP sound).


In summary - Over all, I tried these tubes with many genera: rock, pop, Jazz, Acoustics, Classical, Voices (male and female). These two tubes are very good, I think it has to match your music preference to get the most of it.

If Ihave to describe the sound and make compariosn, the Telefuken is youg energetic teens with a bit of attitute. The Mullard is like a 50 years old who has seen the world, experienced calm and poise.

If you read to this end... Thank you for taking your time to read my layman. Pls comment if you have them.

[Tom-s]

Another European tube comparison ECC82 Telefunken (Berlin) vs 6211 Telefunken (Ulm).

Does a 6211 work in Crack? Yes it does. T1/T5 read 70-75+- Volts DC with 237 Ohm R1 in a Speedball Crack.

I can be short about this one. The 6211 is like a ECC82 Telefunken only better.

The extra Telefunken layer in the very 3D soundstage is there, or even more then with the normal ECC82.

It's not sharp in any way. Very dynamic and lot's of detail retrieval. Air, air, more air .

The downside is that i found these tubes to be rather expensive (75-100€/piece) compared to a normal Telefunken (35-50€).

To add to the comparison above i might try these vs the CV491 tubes i got (my favorite British ECC82's).

[Paul Birkeland]

The 6211 also has extra gain that isn't convenient.

[diynewbie]

Silly tube question.  How does one tell when the amplification tube or cathode follower tube is reaching the natural end of it’s useful life.  I’m not talking taking about a bad tube, but one that is beginning to die a natural death.

Are there audible sonic changes?  Are there simple voltage measurements that can be made to verify that the tube is nearly spent?

[attmci]

Silly tube question.  How does one tell when the amplification tube or cathode follower tube is reaching the natural end of it’s useful life.  I’m not talking taking about a bad tube, but one that is beginning to die a natural death.

Are there audible sonic changes?  Are there simple voltage measurements that can be made to verify that the tube is nearly spent?

I'll use a tube tester.

[Paul Birkeland]

You'll notice a fuzzy distortion, but it will appear very slowly.