James (theheadampbuilder) sent me some pictures of my newly finished BHC Speedball. It will be shipping out tomorrow or Thursday. I’m looking forward to it. The past 2 weeks without a BHC have kind of sucked.
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That Chatham is a sexy bastard. How does it sound?
Sounds great! Little more full sounding.
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I’m looking for reasonably priced (and available) tube upgrade options for my Crack. For the preamp tube, I was thinking I would start off with the Philips ECG JAN 5814A based on @Hazi59 recommendation. Does anyone have recommendations for a power tube?
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I don’t roll a lot of tubes and haven’t heard most of them so I can’t give you any first hand opinions. However, I’ve compiled a list of the tubes that people generally recommend:
Input tubes:
Mullard, Brimar, and other British made NOS tubes tend to have the same warm signature with the liquid velvety mids.
- Siemens Silver Plate ECC82
- Mullard CV4003
- Telefunken ECC82 smooth plate
- Mazda/Matsushita 12AU7/6189
- RCA 12BH7A
- GE 5963
- CBS Hytron 5814a
- RCA “Clear-top” 12AU7
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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Tung-Sol 7236 Tube
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Cetron 7236
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Cetron 5998
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RCA 6AS7g
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Mullard CV2984 Tube
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Mullard 6080 Tube
You can also look through this page and find tube “ratings”: https://www.superbestaudiofriends.org/index.php?threads/bottlehead-crack.120/page-3
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I’ve actually been enjoying the Matsushita 12AU7 quite a lot. For the price, it’s one of the better 12AU7 tubes I’ve tried. Can be found for around $30 bucks or so.
For power, I’ve got a couple of RCA 6AS7G. I haven’t tried any other power tubes, but they seem to provide a lot of bang for the buck as well. Another tube choice you can find strong examples of for around $35 bucks.
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I bought my power tubes from these guys. Great prices. Email for stock.
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Without any comparison beyond what came with the crack I’ll say this guy is a beaut
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Man that white pops! Looks great! What did you use on the wood?
Minwax Natural Wood Stain + Minwax Semi-gloss fast drying Poly (2 coats). Came out better than I thought it would. 
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These were the two tubes that came with my Crack. Can you all help me identify them? The input tube is a 12AU7. But the most of writing was worn off so I can’t identify the manufacturer. The RCA power tube is marked 56-39 and I think it’s a 6080?. The other RCA tubes I’ve seen being sold have different numbers printed on them. So I wasn’t sure.
UPDATE. I think this is a Westinghouse 12AU7? Based on this listing
The top one looks like it could be a Hytron 12AU7.
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Does anyone know what the wood with the kit is finished to? I was expecting something much rougher but it seems pretty smooth
Started the wood and finishing work today. Brought the metal parts to a coater to get finished. I also found some shielding paint from back in my guitar building days. Maybe ill have enough to shield the inside like others have done with the copper sheets
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The long strips are then sent though a widebelt sander with the best face up where the last head runs a 220 grit abrasive. This is the final outside face.
Found this Reddit post in a Headphonesty article.
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Good to know. If i knew that i would of done a quick 220 only to sure things up. Well i did a 150 then a 220, a little extra work but ill say it got things evened out and dirts and oils on the surfaced taken out. I wiped it down with naptha to clean it and raise the grain before a final pass and to see what it would look like with just truoil.
Its safe to say i just have a very plain jane piece which finalizes my finishing plans. I am going to bring it to my friend who sprays and am going to go for a transparent black. You can still see the grain but it will hide some of the darker streaks and knots.
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Step 1 in the books. I had it laid out preglue im a wY that there was virtually no gaps, the wood is close but not perfect.
I asked my dad to help hold it since i dont have a box jig and i get it glued and near perfect, but he kind of heavy handed it and pushed a side in a little too much. At that point the glue dried just a little too much and i couldnt get two of the corners back flat. A little annoyed as my dad always tries to help too much and this happens a lot. But i knew the risk and i try to include him.
Im hoping the finish fills it in a bit
The clamps are on extremely light. Just touching to stop any glue expansion from pushing things out.
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