Tube Rolling w/Crack

[JamieMcC]

A lot of the dealers also have ebay outlets by the way. Generally I don't buy from anyone with under a 99% feed back rating and I normally check to see what negative feed back was given for.



 

[Maynard]

Hi there anyone know how a valvo ecc88 will go in the crack replacing a rca cleartop? A TYP : ECC82 12AU7 18mm long Plates 45° D Getter valvo to be precise! Thanks in advance:) oh an ill be using with a svetlana 6h13c btw.

[mcandmar]

ECC88 or 82?   two very different tubes.

[galyons]

If you actually mean ECC82, then yes.  If you actually mean ECC88 then....Generally, even though the two tubes have a similar base and pin-out arrangements, they are not considered a direct substitutes for each other.  The ECC88 heater current is 20% higher, the transconductance nearly 400% higher and the amplification factor is 50% higher, (mu of 33 v. 20).  That being said it will probably play without harming the circuit. 

PB is the designer and, IMO, best qualified to give a definitive response, since the circuit was not designed for the 6DJ8/6922/ECC88 tubes.

Cheers,
Geary

[Maynard]

Eec 82 sorry yes this won't work in the crack

[mcandmar]

ECC82 is euro speak for 12AU7 so it will work fine.

[howzz1854]

Concur.  I have a Bifrost that I use with my Crack. Stunning sound.   Now get you a Western Electric 421A if you want to push it further.

what sort of improvement will i see with a WE 421ZA?

[denti alligator]

I've got a Crack on order. What tubes will sound best with the HD600s?

[JamieMcC]

I've got a Crack on order. What tubes will sound best with the HD600s?

I would see how you like the stock ones first, then if you want to tweak the presentation we could off suggestions. The stock tubes you receive with kit are a bit of a lucky dip.

[skyfail]

Guys I just scored some Amperex bugleboys on ebay.Can you please check them out and tell me if these are the same "much talked" about 12au7 bugleboys. I was just fooling around ebay and placed a cheeky bid on one of them and the seller accepted . Now I am in a dilemma of whether it will be worth it to buy them.
 
Current tubes :-
Sylvania JAN-CHS 12au7
Westinghouse 12au7 no: 337
BEL 12au7 [indian tube]
Tungsol black bottle/glass
 
 
Links of the Amperex bugleboys  :-
//http://www.ebay.in/itm/AMPEREX-ECC82-BUGLE-BOY-HOLLAND-12AU7-PERFECT-BALANCE-SMALL-LOGO-VINTAGE-1959-/331395728784?ssPageName=ADME:L:COSI:IN:1123
 
///http://www.ebay.in/itm/AMPEREX-ECC82-HOLLAND-12AU7-K64-FOIL-GETR-LONG-PLATE-VINTAGE-1958-BUGLE-BOY-/331397907294?ssPageName=ADME:L:COSI:IN:1123
 
Do check the above links and let me know if I should go ahead with the deal.
 
Cheers.

[denti alligator]

I would see how you like the stock ones first, then if you want to tweak the presentation we could off suggestions. The stock tubes you receive with kit are a bit of a lucky dip.

Really? So the kits can come with different tubes, depending on what's in stock?

[Paul Birkeland]

Yes, some kits have even shipped with Amperex and Mullard 12AU7's.

[Klots]

Hi! Few quick question.

I know that there has been many talk about mod to use E80CC tube in crack, but I ordered a E80CC tube and a speedball few days a go. Tube will arrive next week and speedball will arrive in January I guess, so my question is. Can I use E80CC tube in my un-modified crack (5998 as output tube) until my speedball arrives or just to test it for a evening? I just dont want to ruin anything in my crack, but my CBS5814A broke to pieces yesterday and this rca 12au7 that came with my crack is very microphonic and it is not nice to use it.

And my 5998 tube is making some high pitch squeal/whistle. When I tap on the tube, it goes away. All voltages etc are correct. I resoldered every joint and nothing changed. This sound appears about 30min after turning amp on. Is it common with tubes that they can produce such a high pitch sound and can it mess something up in my Crack? Can anything else cause this high pitch sound?

Thanks!


EDIT: Made a video about the squeal with my phone.  

[Paul Birkeland]

Yes, the E80CC will work in the stock circuit, it just isn't optimized for that particular tube.

-PB

[John EH]

what sort of improvement will i see with a WE 421ZA?

It's considered to be the Cadillac of the 6080 types.  Some folks prefer the Chatham 5998.  I have both and prefer the WE421A although I have to say this and I may be crazy but one of my Cracks has a JAN 6080 that looks like it went through a war and it may be the best sounding one I have.