The KillerDAC Audio forum

Tech Corner => Tubes => Topic started by: data on September 13, 2014, 08:42:16 AM

Title: Interpreting tube measurements?
Post by: data on September 13, 2014, 08:42:16 AM
Hay guys

I ordered a pair of NOS MELZ 6SL7 equivalents to use in my ear clone, the seller stated the following as measurements of the two.

6n9s
N tubes Ia1 Ia2 S1 S2
mA mA mA/V mA/V
1 2.52 2.44 1.64 1.60
15 2.4 2.4 1.64 1.68

What I'm stuck on is the first numbers, being a "1" and the other "15"?

Help a noob out :)
Title: Re: Interpreting tube measurements?
Post by: omodo on September 13, 2014, 09:28:55 AM
I'd suspect it's just the tube number or identifier from his batch/lot of tubes
Title: Re: Interpreting tube measurements?
Post by: data on September 13, 2014, 09:59:25 AM
Thanks, mate :)

I thought it may be that, but being unsure I thought I better check with you guys, one has well matched halves so that one is definitely useful , but it depends on how well the ordinary Russians in there already.. are matched.

Heard good things on the MELZ tubes, should be interesting.

Thanks
Ian
Title: Re: Interpreting tube measurements?
Post by: stevenvalve on September 13, 2014, 05:13:19 PM
Hay guys

I ordered a pair of NOS MELZ 6SL7 equivalents to use in my ear clone, the seller stated the following as measurements of the two.

6n9s
N tubes Ia1 Ia2 S1 S2
mA mA mA/V mA/V
1 2.52 2.44 1.64 1.60
15 2.4 2.4 1.64 1.68

What I'm stuck on is the first numbers, being a "1" and the other "15"?

Help a noob out :)
mA/V......... looks like the valve tester measurements, Milliamp per volt.
Title: Re: Interpreting tube measurements?
Post by: data on September 13, 2014, 05:45:24 PM
Cool, was just unsure of the first numbers.

Hay Steve, have you used these MELZ 6SL7 equivalents?

Do they rate to your ears?

Cheers
Ian

Maybe I should have asked this before placing an order.
Title: Re: Interpreting tube measurements?
Post by: stevenvalve on September 14, 2014, 12:28:45 AM
Give me a link to them.
Title: Re: Interpreting tube measurements?
Post by: data on September 14, 2014, 08:04:55 AM
http://www.ebay.ca/itm/231277920378?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
Title: Re: Interpreting tube measurements?
Post by: data on September 19, 2014, 04:26:04 AM
Well i have no idea how the second link I posted wasn't even a 6sl7 equiv' Bloody I was not looking hard enough as it was a 6sn7 eqiv'.

Either nobody noticed or maybe looked  :D

Other seller still hasn't posted those other and not responding to messages *sigh* hope it isn't a dude seller.
Title: Re: Interpreting tube measurements?
Post by: vitavoxdude on September 19, 2014, 11:41:22 AM
:( Suggest you immediately lodge a case with eBay if it has been a week and no further communication from the seller.  Paypal will cover you if it is proven that the seller is a fraud, I have had to use this service several times.  No. 1 rule, never pay direct into a bank account unless its a registered business.
Title: Re: Interpreting tube measurements?
Post by: data on September 19, 2014, 01:14:38 PM
No, It's all good he just took a little while to get them posted and getting back to me.

The map shows him close to Ukraine border, so I think he is doing well to send them.....tubes are just tubes....I hope he and his family is safe!

But thanks all the same, 'dude :)

He is over the other side of Ukraine, so probably OK.
Title: Re: Interpreting tube measurements?
Post by: data on October 01, 2014, 09:17:52 PM
Damn! slept late and missed the delivery :(

Need to get to post office at opening in the morning.
Title: Re: Interpreting tube measurements?
Post by: Jehuty on October 01, 2014, 09:43:33 PM
Damn! slept late and missed the delivery :(

Need to get to post office at opening in the morning.

Still having the insomnia problem Ian? I am also a night lurker during the weekends as I enjoy my listening sessions during night time  ;)

Please let us know if you like the Russians. I have not found any Russian tubes that I really like. I always prefer the old stock American and British tubes.
Title: Re: Interpreting tube measurements?
Post by: data on October 02, 2014, 11:19:53 AM
Hay buddy.

Yeah, I love the cleaner mains of late night listening, was great when I lived on a country property. Not as easy to do in a unit in suburbia now, unfortunately :(

Ah, I am a tube type deficient kind, and haven't used any of the RCA, Tung Sol and other NOS tubes or even the new production 6SL7 types so I can't compare. What I can say of these is they have that basic even handed presentation that the common ones have, they just seem to do everything a little better than the common ones.
That's straight out of the box (or cardboard and paper wrap in this case).

I only got two tubes so have them in the input and output positions in the EAR clone. I'm not sure if these are worth the price some of the stores and sellers ask, but I'm happy at the lower price I paid.

So bottom line is that... with nothing much to compare with, I'm not much help. I don't think they are going to WOW! people with any one aspect like some of the NOS tubes do.......again I am only speculating.

I wish I could be of more help.

Edit: Hehe...one thing this change does reinforce for myself is, that I... like the rest of us here am not affected by expectation bias as much as some folk believe it does across the board, with everyone. I had read some people on the net saying that these tubes blow all the NOS British, European and American ones away! So these experiences are always valuable in one way or another :)
Title: Re: Interpreting tube measurements?
Post by: data on October 02, 2014, 11:43:36 AM
Hmm...or am I minimizing this all, just so I don't look like an ass on this forum where so many have so much more experience than I do? Not to mention better systems.
Or is the difference even that the capacitance via the miller effect of these are lower than with the common ones, and my 2M Bronze is just happier now.

Should I rethink things after some burn-in time... even?

So many things to consider, or to ignore  :D

****I better add... that I originally was loaned an EAR clone from Jasper made by the same guy and also using 6SL7's, he had a mix of Sylvania's and I think Brown base RCA's. while it didn't have the same detail retrieval I'm hearing with these, his had more slam and musicality...and very possibly more 3D sound scape....  going off memory. And his clone didn't have Duelund outputs, Musicap coupling caps ect' so a safe bet to say, that if looking for the magic that the other NOS tubes can give, these Russians are not the ones to be look at.
Title: Re: Interpreting tube measurements?
Post by: Jehuty on October 02, 2014, 08:10:04 PM
Hi Ian,

For 6SL7 I like the red base RCA 5691. They're relatively cheap compared to the holy grail brown base Mullard ECC32 but at least double the price of your Russian tubes. The red base RCA were rated for 10,000 hours so in my opinion they're worth the extra money. But then system synergy comes into play as well so there's no absolute and the Russians might be better in your system.

At the end of the day, as long as you're happy with your system, that's what matters the most  :)

Cheers,
Wil
Title: Re: Interpreting tube measurements?
Post by: data on October 02, 2014, 09:08:40 PM
I think i need to get some RCA Red bases as a Xmas pressie for myself ;)
Title: Re: Interpreting tube measurements?
Post by: stevenvalve on October 02, 2014, 09:17:56 PM
Data, send your address via PM. I will send you some to try. You pay postage $8.00
Title: Re: Interpreting tube measurements?
Post by: data on October 02, 2014, 10:25:56 PM
OK, no rush......will need to do so on Wednesday.

Cheers, Steve.

Should be very interesting to say the least.
Title: Re: Interpreting tube measurements?
Post by: Jehuty on October 02, 2014, 11:19:35 PM
Data, send your address via PM. I will send you some to try. You pay postage $8.00

Ha! Santa has spoken...or should I say the Valve Buddah!  ;D
Title: Re: Interpreting tube measurements?
Post by: data on October 04, 2014, 05:49:25 PM
The MELZ tubes have burned in some now, and are sounding pretty nice.....a far cry from their poor common cousin  :)
Title: Re: Interpreting tube measurements?
Post by: data on October 14, 2014, 04:35:05 PM
Steve was extra nice, as he sent me both gray and black plates to try out  8)

Trying out the grays first, impressions to follow
Title: Re: Interpreting tube measurements?
Post by: data on October 14, 2014, 06:17:56 PM
Hmm...taking a brake till the winds die down, as I'm getting static shocks when I touch the turntable controls every time I need to flip a record  >:(

Nothing new for a day like today.

Well, the gray plate RCA's have a fuller more weightier presentation than the MELZ metel base tubes. More layers are evident, and piano hammer strikes on the strings a more natural sounding.

IF I classed the common Russians as "Fair" (they amplify sounds), I would class the MELZ tubes as "Good", but the gray plate RCA's step up to "Very Good". They add a more emotive quality.

I was afraid it was going to play out like this, and have yet to give the black plates a run  :D
Title: Re: Interpreting tube measurements?
Post by: vitavoxdude on October 14, 2014, 08:26:02 PM
Static charge is a real PITA.  Do you have carpets fitted in the same room?  If so lift them and place conductive tape onto the underside and then drain it to a separate earth stake, that should dissipate the electrical build up and make your equipment last longer.  Pesky IC's do not like having static shorts put across their terminals and could result in failure later.

A friend of mine had the same issues with his system, the earth drain worked dandy and he is no longer in fear of touching the volume control etc.

Keeping the air moist in the room also helps but synthetic carpets coupled with AC which dries the air all adds to the static build up, your equipment is referenced to earth and hey presto, a blue spark leaps form your finger when going near the controls.  Vinyl is particularly susceptible to static build up which attracts dust and other crap to it like a magnet.  The 'zerostat pistol' works well to counter the build up, do you have one?

Good to hear Buddha sorted you with some tasty valves
Title: Re: Interpreting tube measurements?
Post by: data on October 14, 2014, 08:41:09 PM
Thanks for the tips :)

Although i can't do jack on the carpets (rental), when you say "Pesky IC's" do you mean integrated circuits? if so I only have some in the DD table as everything else is tubes.

Everything was shocking me today, sliding doors, and the car! the damn car! is the worst offender, had to get some fuel and was so paranoid about static when i was at the pumps  :(

Yeah, Steve's great and very generous in allowing me to try these, and I am listening to the black plates now, and while I was unsure I would hear a difference between them and the grays, they are again a bit better.............damn it! Holy Cole is a touch more seductive and i like it......will have to save for some of those  8)
Ricky Lee now...

Title: Re: Interpreting tube measurements?
Post by: data on October 14, 2014, 10:32:02 PM
I'm not sure if I have it right, but these black plates seem to be maybe quieter? they sound a little more refined and sweeter than the grays.

Sorry, thinking out loud as usual.
Title: Re: Interpreting tube measurements?
Post by: stevenvalve on October 15, 2014, 01:10:19 AM
Some feel the RCA 5691s black plates have a richer, darker, blacker sound, and very good timbre.
Title: Re: Interpreting tube measurements?
Post by: data on October 15, 2014, 08:47:47 AM
Sometimes I think I'm a little terminology impaired  ;)

My use of the term "refined" could mean a few things when I think of it, but I get the richer, blacker and more textured :)
Title: Re: Interpreting tube measurements?
Post by: data on October 15, 2014, 11:42:45 AM
I still have maybe only 30 hours on the MELZ, so will pop them back in and compare after the weekend.

It's been very interesting and fun so far.

Edit: Ah, no need to compare anymore, these RCAs are just better sounding  :D
Will be sending back during the week, but now know these will lift things to a better level in my system, when i can get some.

I have really appreciated being able to try them  8)