Anyone familiar with MDB Ventures? Tube source?

[Phil_S]

http://www.fourwater.com/

Has anyone done business with these guys or know anything about them? They are located in Milwaukie, OR. I sent an email last night (I'm on the right coast) and had an answer this morning that was time stamped 6:47AM and it seems to be a human answer, not a bot.

The website says they sell tested tubes for reasonable prices and reasonable shipping. I think I'm going to buy a few cheap 6SC7's that appear to test OK. Someone here gave me the bug for a tweed Bassman.

Then, they have the bargain packs http://www.fourwater.com/bargain/bpacks.htm and I think I'm going to order 1 pound of 7/9 pin tubes (about 50 tubes) and 2 pounds of octal tubes (about 28 tubes). I have a shipping quote from them and the incremental cost for tubes by the pound, including shipping is about $10. I figure, if I get one decent tube I come out even, two I'm ahead, so I'm willing to take the chance. If I get no usable tubes, let's say I've paid more for less of an education and I bet I can dump them on eBait for what I paid.

[ampdoc1]

Cheap enough to try, but it looks like very few of the tubes shown are commonly used in guitar amps. Not to say others couldn't be used, but you probably won't find much info on this or other amps sites to guide you.

a'doc1

[ampmike]

Yea.Cool site.Who knows after doing some reading there all my tubes could be leaky.Im going to get some tubes from them as well,Thanks Phil

[Phil_S]

ampmike, thanks for the encouragement! I just spent $30 for three metal 6SC7's that are represented as testing good for emission and transconductance, plus 1 pound of 7/9 pin tubes ~50 and 2 pounds of octal ~28. So, when it arrives, it will be fun with tubes day and I'll hope among the 80 or so loose tubes I can find a good one.

They say they will overfill by 10% on the loose tubes to compensate for breakage, so it could be more like 90-100 tubes. If you read the bargain bin notes, they say these are pulls from salvaged equipment, so one can hope for used but not used up preamp tubes. I'm doubtful on any power tubes.

The total shipping cost they charged is $12.70. I figure it will be hard to get a USPS package below $5. On this basis I figure the loose tubes cost me about $9. That's not much of a gamble hoping for only one useful tube and it tempers the disappointment factor.

Shipping is via USPS from Oregon to Baltimore, so I think it will be a week or more before they arrive. I'll post when the package comes.

[Structo]

They are just up the road about 40 miles North of me, although I never heard of them.

No retail store, just online.

I browsed the tubes for a bit but didn't see anything that really interested me.

[Phil_S]

Yeah, Google found them when I was hunting for some 6SC7's. I bought 3 of those. They are not a guitar tube shop, that's clear and you won't be getting a pile of Mullard ECC83's for $10 a pop! I just paid a small fee for some entertainment. I'll let everyone know how entertaining, even it's a total bust!

[Phil_S]

The box arrived late today! Tubes were very well packed. No breakage at all. Of course, I got the 3x 6SC7 and I'll see how they are when I build something, maybe a 5B6.

I ordered 1 pound of "mini" tubes 7/9 pin. I'm guessing there were 50+/-, but nothing to write home about. Most are not useful, starting with numbers we don't use, like 2, 3, and 4. There were 3x 6AU6 - 2x GE, 1x Philco (Sylvania?). There was one 6LX8/LCF802 pentode/triode Made in Holland, etched maker code 66G, branded Emerson/Zenith. This may be the worst $1.00 I ever spent, not much to show

I ordered 2 pounds of octal tubes -- maybe 40+/- in the lot. Fared somewhat better here. I feel like the rectifier king! The first tube out of the box is a coke bottle Sylvania 5U4G marked "NG" Then there were 3x 5U4GB, 5R4GTB, 4x 6X5, 1x 6F6GT National Union, one 6SQ7GT like half 6SL7) GM brand metal base. If it works, the prize may be one RCA 6SJ7GT. There were about a dozen TC tubes. This was the best $0.20 I've spent in a while!

So, how do I figure out if a rectifier has much life in it?

[renshen1957]

National Union, one 6SQ7GT like half 6SL7) GM

Hi,

An older post, however, the 6SQ7 has a mu of 100, more like 1/2 of an octal version of the 12ax7, or an 6ax7 without two diodes.

Best regards,

Steve

[M Fowler]

I built the Gibson EH150 using 3 6SQ7 preamp tubes first metal and then switched to GT when I sourced some on ebay. Using o'rings on them.

Mark

[Blackburn]

Good to hear you might be doing a 5B6, Phil! That circuit likes being PTP. I'm looking forward to my next one. I got my NOS octals from TD, and not for too much dough if I remember right. A Raytheon 6SL7 and Haltron 6SC7.

[Phil_S]

Oh, I built that 5B6 a while ago. I really like it. The cheap 6SC7's from MDB all seem equally good (or bad; I have no frame of reference.) https://tubeamparchive.com/viewtopic.php?t=20699 I had a couple of problems that good TAGers helped me sort out.

I've been working on the cab for quite some time. I've got a back panel made and still need to get a front panel made. I was hoping my friend with the full wood shop would mill a scrap of something nice in his planer to 3/8" thick but he took a spill off his bicycle an tore up his shoulder inside. I don't have the nerve to ask if he expects to be in the shop soon. I made the back from birch plywood but could only get one decent piece -- the others had face plugs. Maybe the art supply store has some new stock and I'll get another nice one. I'll post pics when it's done.

[M Fowler]

I ordered two Tungsol 6SC7GT tubes from that website yesterday, we'll see how they turn out.

[johnnyreece]

Dredging up an old post, but I thought I'd say thanks for pointing this place out. I ordered a tube caddy loaded with tubes. Lots of old TV tubes, but I did get a few gems. Most notable, some 12BH7's in mis-marked boxes. I got several 6w6GT, a couple 5Y3, 6J5's, and a few 6K6GT's. I've sorted out probably 1/3 of them that were completely wrong filament voltages (anyone need some 50L6's?), and still need to get through some of the others to see if they're worth keeping. When I get down to the ones I might actually use, I'll start testing. Several of them looked NOS. We'll see if I can sell any of the ones on eBay to make some money back (because why not).

Mostly, I just wanted the caddy because I'm outgrowing my plastic storage bins, and the price on this was $20. It's not in great shape, but it has a cool vibe to it. Shipping was murder, but I discovered it's because I had two packages. I also bought some inexpensive lots of 6J5GT, 12AV7, and 6SJ5's.

All in all, it's like Phil said; a small fee for entertainment.