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post #6061 of 10574

Thanks gibosi.

 

I've been reading quietly for last 3 weeks . My head is spinning trying to get it all in. On 6HM5, short ones are not recommended . Should I just get russian 6HM5? Which are 6.99 with free shipping for each.

 

Thank you

post #6062 of 10574
Quote:
Originally Posted by CITIZENLIN View Post
 

Thanks gibosi.

 

I've been reading quietly for last 3 weeks . My head is spinning trying to get it all in. On 6HM5, short ones are not recommended . Should I just get russian 6HM5? Which are 6.99 with free shipping for each.

 

Thank you

 

Russian? I don't think I have ever seen a Russian 6HM5....  I have tried and liked the GE's. And others here have tried and liked the Sylvania and the EI (made in Yugoslavia).

post #6063 of 10574

My bad , I meant EI Yugoslavia. GE or EI ?

post #6064 of 10574

Hi CITIZENLIN,

 

Several people tried this tube and liked it.

 

http://www.ebay.com/itm/6HM5-6HA5-EC900-export-quality-audio-triode-tube-NOS-FREE-SHIPPING-/300879467071?pt=Vintage_Electronics_R2&hash=item460dd0523f

 

When I bought a pair the seller accepted $5 each shipped - try it.  This tube was made by Ei in Yugoslavia. When it starts up there may be a flash of light, but it is nothing to worry about - just a quick start feature.

post #6065 of 10574

Hi Gibosi,

 

Received a lot of seven 6080 tubes. They are from different years; all but one of them is made by RCA, the other one is a GE. They sound different, perhaps because of slightly different construction and usage.

 

The best of these, a 1956 and 1960 RCA and the GE, sound very good with a very strong punchy bass which pairs very well with my Audio Technica headphones which are bass shy.

 

In comparison to my Coke Bottle 1976 RCA 6AS7G tube the 6080's have better bass, but the 6AS7 has more detail. These 6080 tubes also play louder than the 6AS7 although both have an amplification factor of 2.

 

At this time the nod goes to the 6080. However, what I really would want to do is to use these 6080s as power tubes, but I haven't figured out how to do it. Perhaps buying two octal breadboards and two 9-pin socket extenders. Then use solid 18 gauge insulated copper wire (which is the same thickness as the tube pins) and connect the wires to screw terminals on each breadboard. The other end of the wire I could just strip and push down into the socket extender.

 

Two separate wires would go to an external power supply rated 10A. Do I need two external power supplies, or would one do? The 6080 tubes draw 2.5A each.

post #6066 of 10574
Quote:
Originally Posted by CITIZENLIN View Post
 

My bad , I meant EI Yugoslavia. GE or EI ?

 

Unfortunately, I tried the GE, but didn't try the EI, so I really can't say which....  But as cheap as these are, why not try both? :)

post #6067 of 10574
Quote:
Originally Posted by gibosi View Post
 

 

Unfortunately, I tried the GE, but didn't try the EI, so I really can't say which....  But as cheap as these are, why not try both? :)


haha you are right but I am trying to save money for C3G setup. You know adapters so expensive.

 

 

 

Quote:
Originally Posted by mordy View Post
 

Hi CITIZENLIN,

 

Several people tried this tube and liked it.

 

http://www.ebay.com/itm/6HM5-6HA5-EC900-export-quality-audio-triode-tube-NOS-FREE-SHIPPING-/300879467071?pt=Vintage_Electronics_R2&hash=item460dd0523f

 

When I bought a pair the seller accepted $5 each shipped - try it.  This tube was made by Ei in Yugoslavia. When it starts up there may be a flash of light, but it is nothing to worry about - just a quick start feature.

 Thank you mordy. I think I will try those (EI). 

 

Thank you guys. Without you guys, I would've been still playing stock set up on my MK IV. Then again thank you very much for letting spent ton of mula. :)

post #6068 of 10574
Quote:
Originally Posted by mordy View Post
 

Two separate wires would go to an external power supply rated 10A. Do I need two external power supplies, or would one do? The 6080 tubes draw 2.5A each.

 

Probably you would need two external power supplies.... The reason I say this is I haven't seen a cheap voltage regulator that I am confident is good for 5A. All those I have seen that are labeled 5A add something like "Recommended for use in the 4.5A". So I am not sure it is a good idea to try to draw 5A through one of the these.

 

Similarly, I have been thinking about running a Cetron JAN 6336B in my LD1+. However, this is a 5A tube. And I just don't know how to interpret "Output current: 0-5A. Recommended for use in the 4.5A."

post #6069 of 10574
Is the 6hm5 a direct plug and play?
post #6070 of 10574
Quote:
Originally Posted by Rossliew View Post

Is the 6hm5 a direct plug and play?

 

Yes it is. Set your LD for EF95 tubes and it is plug and play.

post #6071 of 10574
Quote:
Originally Posted by gibosi View Post

Yes it is. Set your LD for EF95 tubes and it is plug and play.

Cheers! I ordered a pair and realized it might not be a direct plug in Lol!
post #6072 of 10574

Hi,

 

I was intrigued by the subminiature frame grid dual triode tubes that supposedly were the pinnacle of tube development. Once Gibosi showed us how you can use them connected to a breadboard I decided to take the plunge. These tubes are supposed to be strong enough to withstand nuclear radiation and survive tremendous vibration and G forces.

 

Found a deal on an unknown dual triode Raytheon JAN 6832 from 1957 with characteristics similar to the 6SN7 tubes. Paid $7 shipped for a pair (received three). [I believe this offer is still available if you want to try them.]  My retired engineer friend helped me to solder little 18 gauge solid copper insulated wires onto the leads. These copper wires are the same thickness as the socket holes in the LD amp. Gibosi provided the wiring diagram and instructions how to connect the little octopus thing.

 

I used little plastic pin protectors that came with Mullard tubes as a numbering guide, putting a sticker on the perimeter and marking the leads 1-7 (I know, there are eight leads, but I'll leave it to you to figure out). No external power supply is needed since these tubes work on the standard 6.3V and draw 0.4A. To keep things solderless I used cable ties to keep the wires more or less in place.Here is a picture comparing the size of a 6AS7 with the 6832:

 

Here is a work in progress - the experimental setup using the Vectors (disconnected from the breadboards). It looks like a dangerous spider web. What is left is to insulate the wires in case they end up touching each other. My engineer friend suggested nail polish on the bare wires. I am going to ask one of my grand daughters for a color they don't use any more, green, purple, black or whatever....

I do not have any humming problem unless I turn up the volume too high which is the same as with most tubes I use.

 

 

Now, after having all this fun and brain and finger exercises, comes the best part - this sub miniature dual triode sounds excellent. Powered by a near pair of RCA 6SN7GTB tubes this 5837 has punchy solid bass and great extended highs and a balanced, detailed, coherent, and lively presentation right out of the bubble wrap. (No boxes and no markings on the tube.)

 

The frame grid construction is said to use wires that are so thin that the naked eye cannot see them. The prized 6DJ8 tubes are also said to use frame grid construction. Perhaps this has to do with the excellent sound.

 

My set up seems very fragile so I think that I have to limit my toe tapping LOL.

 

Happy tube rolling!


Edited by mordy - 5/9/14 at 12:08pm
post #6073 of 10574
Quote:
Originally Posted by mordy View Post
 

Hi,

 

I was intrigued by the subminiature frame grid dual triode tubes that supposedly were the pinnacle of tube development. Once Gibosi showed us how you can use them connected to a breadboard I decided to take the plunge. These tubes are supposed to be strong enough to withstand nuclear radiation and survive tremendous vibration and G forces.

 

Found a deal on an unknown dual triode Raytheon JAN 6832 from 1957 with characteristics similar to the 6SN7 tubes. Paid $7 shipped for a pair (received three). [I believe this offer is still available if you want to try them.]  My retired engineer friend helped me to solder little 18 gauge solid copper insulated wires onto the leads. These copper wires are the same thickness as the socket holes in the LD amp. Gibosi provided the wiring diagram and instructions how to connect the little octopus thing.

 

I used little plastic pin protectors that came with Mullard tubes as a numbering guide, putting a sticker on the perimeter and marking the leads 1-7 (I know, there are eight leads, but I'll leave it to you to figure out). No external power supply is needed since these tubes work on the standard 6.3V and draw 0.4A. To keep things solderless I used cable ties to keep the wires more or less in place.Here is a picture comparing the size of a 6AS7 with the 6832:

 

Here is a work in progress - the experimental setup using the Vectors (disconnected from the breadboards). It looks like a dangerous spider web. What is left is to insulate the wires in case they end up touching each other. My engineer friend suggested nail polish on the bare wires. I am going to ask one of my grand daughters for a color they don't use any more, green, purple, black or whatever....

I do not have any humming problem unless I turn up the volume too high which is the same as with most tubes I use.

 

 

Now, after having all this fun and brain and finger exercises, comes the best part - this sub miniature dual triode sounds excellent. Powered by a near pair of RCA 6SN7GTB tubes this 5837 has punchy solid bass and great extended highs and a balanced, detailed, coherent, and lively presentation right out of the bubble wrap. (No boxes and no markings on the tube.)

 

The frame grid construction is said to use wires that are so thin that the naked eye cannot see them. The prized 6DJ8 tubes are also said to use frame grid construction. Perhaps this has to do with the excellent sound.

 

My set up seems very fragile so I think that I have to limit my toe tapping LOL.

 

Happy tube rolling!

 lucky you the last time i checked that tube on 3bay it was $29+ killer shipping.

post #6074 of 10574
Quote:
Originally Posted by i luvmusic 2 View Post
 

 lucky you the last time i checked that tube on 3bay it was $29+ killer shipping.

 

Mordy is using a different sub-miniature than the one I used. The one I used, Sylvania 7963, is expensive, over $20. But he is using a Raytheon 6832. and these are much cheaper. For example:

 

http://www.ebay.com/itm/Raytheon-Jan-6832-Submini-dual-Triode-Matched-Pair-Excellent-NOS-tubes-/271171966719

post #6075 of 10574

I'm  bidding on 3 RCA 6AS7G i hope i can get this one i really want this,preparing for my future CRACK not only that i can still use this tubes with my LD's.:ksc75smile:

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