[wiatrob]

RCA 6CG7 cleartop, Soncicaps, Smeggy's K1K. Amzing kick - the K1Ks take up the slack i had with my output resistor choice, I can make it to about half way!

Haven't had a chance to try any other combos with this setup yet, but I have the Siemens chrome plate here later this afternoon.

I am really digging the SonicCap GENIIs, think this will be my go to...

I mounted them horizontally with the leads bent under in a 't' shape, no noise issues...

 

[smeggy]

heh, the amp looks so teeny. Since adding the bigger caps to mine the e12 keeps tripping every few minutes. Any cures for this?

 

[cfcubed]

Quote:

Originally Posted by smeggy /img/forum/go_quote.gif heh, the amp looks so teeny. Since adding the bigger caps to mine the e12 keeps tripping every few minutes. Any cures for this?

I think we've considered e12 tripping issues solved quite a while back (some resistor value tweaks AFAIR)... Since then many are running non-BoM caps & some have monster big caps (S/Os, Gen Is, etc.) w/o problems.

Maybe a decent pic of your C4 area would help...

 

[sachu]

I don't remember what values i used for the E12 resistor values on Smeggy's CTH build. But am thinking it was the current BOM values.

 

[cfcubed]

Quote:

Originally Posted by sachu /img/forum/go_quote.gif I don't remember what values i used for the E12 resistor values on Smeggy's CTH build. But am thinking it was the current BOM values.

I think the values tweaked for e12, a long time ago, were R13s (1.5k now) & R14/R15 (100k now) and maybe R7E/R9E (2k now)... So you should let us know your values for these. Think some builds may working fine with variances in these tho (.5k for the 1k->2ks).

 

[wiatrob]

Quote:

Originally Posted by cfcubed /img/forum/go_quote.gif I think the values tweaked for e12, a long time ago, were R13s (1.5k now) & R14/R15 (100k now) and maybe R7E/R9E (2k now)... So you should let us know your values for these. Think some builds may working fine with variances in these tho (.5k for the 1k->2ks).

Correct - the most germane would be checking R4E (originally 1.5K now 2K) and R7E/R9E (changed to 2K before the first BoM release).

As mentioned a pic would help, showing how the sonicaps are mounted (I haven't tombstoned, preferring to leave my leads the same length.

I suspect R4E (which may be 1.5k - fine with Bom caps and Wimas, but more sensitive to longer/uneven cap leg lengths) to 2K may solve the e12 trips...

 

[smeggy]

I'll have a look later and check them, I think I have all the values needed if they need changing and I'll shorten/even length the cap wires.

 

[cfcubed]

Quote:

Originally Posted by smeggy /img/forum/go_quote.gif Switched it down to 6v, plugged in the 6n6p and off it flew... nice bass increase over the Siemens and the rest sounds damn nice too. I'm very happy with it especially considering how cheap these tubes are. I like how this sounds a lot

Quote:

Originally Posted by smeggy /img/forum/go_quote.gif I swapped the caps over to Sonicaps thanks to waitrob and it's going great. < snip > It's a great all-rounder and does nothing wrong. The Beta has the most solid sound of the three, with thunderous bass and tight as a drum and very smooth. The EHHA isn't as solid or thundering in the lower regions but has a delightful sense of air and separation with nice atmosphere and the CTH is the more aggressive of them with the 6n6p tube and upgraded caps (tuned that way on purpose). It's a sparkling amp with great bite and clarity and very appealing all round sound. It's hard for me to say one is better than the other because they each have distinct strengths and there's no way I'd say the CTH was outclassed, just a different flavor depending on what I'm listening to. < snip >

Smeggy, I didn't catch which cans you are using... We know there are tube / cans synergies as well as the ever-present sound & music taste influences.

Having just rec'd a pair of broken-in K701s I find those cans do not mate well w/my Siemens 12au7 equiv (a great D2000s match)... IMO that Siemens emphasizes the areas my K701s already do well - BB 6dj8 is a much better match (& probably 6n6p, de-emphasized mids/punchier bass).

Obvious, but reiterating its a good idea for people to search through the CTH threads for tube/cans combos & may need to experiment a bit to get the sound they want.

 

[smeggy]

My cans are custom made orthodynamics (Fostex T50RP) and they show the flavor of each amp very nicely. I don't have any ;standard' cans aside from the K1000. All the others are non standard/heavily modded so not much use as a reference point for anyone else.

 

[wiatrob]

Well, 'cept for my modded YH-3s

 

[Forte]

Quote:

Originally Posted by cfcubed /img/forum/go_quote.gif Having just rec'd a pair of broken-in K701s I find those cans do not mate well w/my Siemens 12au7 equiv (a great D2000s match)... IMO that Siemens emphasizes the areas my K701s already do well - BB 6dj8 is a much better match (& probably 6n6p, de-emphasized mids/punchier bass).

Can confirm the K701 and 6n6p combo works a treat, by far my favorite tube for these cans, really brings out there best.

 

[smeggy]

Cool, it's a great tube for the CTH!

 

[wiatrob]

I'll give the 6N6 another shot this week - since I seem to have misplaced my 6C7 and Siemens Chrome grumble grumble too many tubes to roll...

 

[cfcubed]

Quote:

Originally Posted by TimJo /img/forum/go_quote.gif So yesterday, I did a mini shootout between two of my favorite 12AU7 variants. Both tubes were made by CBS/Hytron ~ the 7730 & the 7318. <snip > There is a lot of similarity between the two tubes. Both produce an enormous amount of detail, with the 7730 winning out a bit, especially with harmonics produced with stringed instruments. It's the only tube I've listened to where you can really hear a lifelike reproduction of the harmonics that are produced from a steel fingerpick breaking contact with a well tuned steel string. It also is able to reproduce the sound of harmonics that are created between the fret and the string with more realism than I have heard elsewhere. That being said, the 7318 does a really good job as well, but not like the 7730 (at least through DT880's). But, after listening to to several albums with both tubes, my overall favorite ends up being the 7318 because of what my ears perceive to be a flatter response across the entire frequency spectrum. It seems like the 7730 dips a bit somewhere in the lower mids, and doesn't have as much bass extension when compared to the 7318. Both tubes are amazing though...

Although I've a boatload of CTH tubes, I've been on the look out for these 7730s or 7318s... Unless I'm missing something they seem quite rare.

Anyway, there's a pair on fleabay now & though I'm loath to spend another $10+ per tube I may not be able to help myself

From what TimJo says it could be worthwhile.

As I only need one of the pair, if they don't go for too much wondering if anyone would want to 50/50 them (with one of us bouncing out the extra tube to the other). If so let's do the PM thing.

 

[wiatrob]

Boomy gave me a 6H1N-EB (6N1p-EV) at the meet...anybody tried 'em? I plopped it in and fired it up...Cool looking filament...sounds nice