Bottlehead Crack

Just thought of an idea. Anyone have access to a laser cutter? cut some plexi sheets and make a clear base to show off the components?

The top is metal for a reason.
It’s grounded so if anything fails and goes live, the fuse will blow.

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I was only talking about the side walls.

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Last I chatted with him his bifrost 2 hadn’t arrived… bf2 = bifrost 2

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you know…I think I’ve asked that question twice, cause being told Bitfrost 2 is ringing a bell as having happened to me earlier, LoL!

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I’ll reply here @Hazi59

Oh nice! Be sure to post your thoughts in the bhc thread. I think I have a good handle on the Mullards sound so I’d like an alternate input tube to hone in my ears on the differences tubes can make.

Any recs? Something quite different would be ideal. Or even a power tube if you think that’s the way to go here.

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Well, Mullard, Brimar, and other British made NOS tubes tend to have the same warm signature with the liquid velvety mids. So for a 12AU7/ECC82 alternative, I would recommend a Telefunken ECC82 smooth plate or a Mazda/Matsushita 12AU7/6189 tube as a good alternative. Also, RCA 12BH7A or a GE 5963 are nice affordable alternatives.

For the power tube, you may want to grab an RCA 6AS7g, Tung Sol or Cetron 7236 or 5998 if you can find one and it isn’t ridiculously priced.

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Sweet, lots of options. Sometimes a pain to hunt these down. Thanks man.

The telefunken looks to be easy enough to find. The ecc82 type drops right in?

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Following to see what you guys like. :+1:

Mine came with the electro-harmonix 12au7 and stock power tube, it sounds pretty good.

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Electro Harmonix is a new production tube made by New Sensor Corp, which owns the new production tubes for Tung Sol, Sovtek, Svetlana, and Genalex. They aren’t bad tubes, but you will definitely get a performance increase with solid New Old Stock tubes.

yes. ECC82 is just the European Designation for 12AU7. Other tubes that can be drop in replaced or substituted are ECC802s, E80CC/6085, E82CC, CV491, CV4003, 7316, 5814, 5963, 6680, 7730, B749 (good luck finding one of those).

You can also can run 12AT7 and 12AX7 tubes, but you have basically no volume attenuation because of the higher mu and gain.

EDIT: I forgot to mention that if you have the Speedball Upgrade installed on your BHC, you can also use 12BH7 tubes. This is cool because these tubes have nice affordable prices at the moment.

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I just got a very nice 7236 this week from a member on Head-Fi. Even with exchange and shipping it was pretty good. It came all the way from North Carolina.

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Those are good tubes…I have a Tung Sol version myself. They are more forward sounding than 6080 or 6AS7g tubes…also more powerful as they have a higher gain and mu. Can be hard to find, especially the Tung Sol and Cetron variants. The 5998 is supposed to be even better, but are really hard to find at the moment.

This one is a Cetron and the price was right.
Wish my DV would hurry up and get here.

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Alex, can you list which 6080 and 12AU7’s you have?

A general tube question: wtf do all the various tube testing parameters mean? I’ve searched for what the normal operating parameters of various tubes should be but can’t find anything useful. Buying tubes that have been measured is useless without knowing what the measurements mean lol. Up to now I’ve either bought new tubes or rolled the dice and got lucky.

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Tung-Sol metal base 7236’s were quite plentiful last year. A ham radio guy was selling them on fleabay for $35 a pop. I bought four from him. Since then, the supply dried up apparently.

They’re quite nice, but I prefer the more laid-back nature and larger soundstage of the RCA 6AS7G’s ('50’s black plates).

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I just picked up one of those on eBay for $20.50 and five bucks shipping. Very happy about that. It’s 30th week of 1960 made and tests at 85/84.

I’ve been working on spiffing up my Crack, it’s finally finished being spiffed.

When I originally got it used , it needed a bit of TLC. It was professionally built and well built at that but the ground plate was covered in a half-assed powder coating job and the box had been bonked in one corner.

Before:

And After:

I’m amazed that the carpenter I took it to said he could fix it with steam and a hot iron. Completely straightened it back up and bull nosed it a bit, gives it a softer period look. I’m very happy with the way it all came out. I spend a lot of time sanding and finishing but it now looks as good as it sounds.

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Something else I thought you guys would get a laugh about. My wife said “Oh you got a new light bulb for your stereo”.

I love that woman so much I’ve stayed married to her since 1989!

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For most woods, if its dented and not huge, you put a moist rag on it then heat it with a soldering iron. This pops it back out amazingly well. It even works with certain finishes as well but not all

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