holy grail tube Bendix 6900

pitdogg2

anyone looking?

https://www.ebay.com/itm/6900-5687-1-BENDIX-NOS-NIB-TESTED-VACUUM-TUBE-Q4/273396596806?_trkparms=aid=111001&algo=REC.SEED&ao=1&asc=20160908131621&meid=f5b40cb3067b4416b0a4f2505d54c99e&pid=100678&rk=3&rkt=15&sd=163179567444&itm=273396596806&_trksid=p2481888.c100678.m3607&_trkparms=pageci:c7a4d7a9-a173-11e8-9d01-74dbd180b1c5|parentrq:43a0ab001650add89e338233fff9a979|iid:1










tung-sol (maybe)



https://www.ebay.com/itm/Pair-Of-Tung-Sol-6900-Vacuum-Tube-Generic-For-5687-Hickok-539B-Tested/163200994106?hash=item25ff898b3a:g:owUAAOSw4hlbcfkT:sc:USPSFirstClass!61705!US!-1

SCompRacer

I recall a pair of Bendix 6900's could easily fetch $800. MU Engineering bought the Bendix Tube Division. They rebranded existing stock and continued to manufacture tubes with Bendix tooling. Before the secret got out, you could buy MU6900's for much less.

pitdogg2

yea Rich I'm interested to see where this one goes.

The Tung-Sol 6900 though has me perplexed AFAIK Tung-Sol never made any or branded any 6900 tubes. Pretty sure they made the 5687 tube although not positive in that respect. They may of re-branded others tubes as their own once again not sure on that.

heiney9

I don't know a lot about tubes I don't use, but I thought the 6900 was a Bendix model and only made by Bendix or as RIch stated MU Engineering.

Just like the Bendix 5992 is basically a 6V6 on steroids. They are unique in their structure and composition. Yet I've seen many other labels on the 5992, but there is no mistaking it's a Bendix tube.

May be the same case with the Tung Sol 6900.

Bendix tubes had their own model number and were designed from the ground up for specific uses. Many times the Bendix tube has been relabeled, but it's the same tube. Like the 6106 rectifier by Bendix for use in units that use the 5Y3. Lots of rebranded 6106's, but they all were made by Bendix. Again a very specific construction and composition. If you're sneaky you can buy the relabeled tubes cheaper sometimes because the seller doesn't know what they have.

H9

pitdogg2

heiney9 wrote: »

I don't know a lot about tubes I don't use, but I thought the 6900 was a Bendix model and only made by Bendix or as RIch stated MU Engineering.
H9

That was my belief as well Brock.

heiney9

If the Tung Sol isn't identical in construction then I don't think it can be considered a 6900 despite the markings or the sellers spiel.

RCA made special "red" tubes 5691 and 5692. They were unique 6SL7 and 6SN7 types w/special construction and bases. Many were relabeled over the years. But some just called them 5691's or 5692's but were standard spec 6SL7's or 6SN7's. The only way to know a "true" 5691/92 was to look at the construction.

I suspect this to be the case with the 6900 and all Bendix tubes.

pitdogg2

yes I have seen that a lot lately with the 5691/92 tubes being plain ol 6sn7 or 6sl7. Seems that tube manufactures were trying to upsell a standard tube for a premium tube there towards the end of the tube era. Those are really easy to spot. this Tung-sol sure looks like the Bendix as I'm sure it is and the seller even has the Bendix paperwork in a picture as well. I sent an email to the seller just to get his/her take on it. Should be an interesting answer

heiney9

I know you know this Ivan, but I cannot stress enough that if one is serious about buying tubes, especially some of the nicer, holy grail types you need to educate yourself on construction. 75% of sellers have no idea what they are selling. They are either mimicking what has been told to them or just assuming it's what the label states.

I am back on the hunt for some very rare and specific American 12AX7's and all I am looking at is construction because any of the American tube labels can be on the tubes even if they didn't manufacture them.

In fact the other day I found a single and it's labeled "Fisher". Leave no stone unturned and ask the seller questions.

H9

P.s. I must add that even though the sellers don't know what they are selling, they are not in most cases intentionally trying to defraud you. They just don't truly know. They see markings like "made in England" and assume it's a Mullard. Look at the construction, look at the codes, etc.

halo

@machone - this may be the tube you want for that Modwright preamp!

machone

Thanks for thinking of me but I'll pass. Too rich for my blood. Saving for a DAC.

pitdogg2

well this went for a pricey sum 500.00 for one tube. Brent Jesse sells these when he has them for 600.00 a pair. I bet this will be re-evaluated by Brent. WOW is all I can say.

stretchl

So... why? Will it be used? Simply stored as an investment? I don't get it.