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Little Dot 2++ Tube Rolling - Page 11

post #151 of 658
Quote:
Originally Posted by yrh0413 View Post
Guys may i know is there any difference between the stock EF92 tubes on the LD2+ compare to the ones sold in online stores? I notice the thread starter's EF92 is Mullard driver tubes (6CQ6 MA - CV131), but those on my LD2+ have the designation 6CQ6 WB and 6CQ6 WM. Any difference?
I don't know what all the coding on the tubes mean, but if a tube has the same brand (for example, Mullard) and number (CV131), I bet it sounds pretty much same, despite the presence of other coding.

Maybe someone else can chime in here.
post #152 of 658
thanks mate. gonna place order on some 4015s.
post #153 of 658
Thread Starter 
Quote:
Originally Posted by yrh0413 View Post
the thread starter's EF92 is Mullard driver tubes (6CQ6 MA - CV131), but those on my LD2+ have the designation 6CQ6 WB and 6CQ6 WM. Any difference?
When I received the LD2++ it came with Ediswan EF92 not Mullard. At that time I had also sourced some Mullard CV131 - 6CQ6 as a rolling option. The Mullard tubes do sound different to the Ediswan. As "thread starter" I supose I should try and clarify the puzzles with some tube markings. From what I gather, the EF92 code was originally for Telefunken - Ediswan - Siemens but not Mullard, they had their own code systems, but it's common for tubes to have codes printed on them which relate to alternate brands, such as finding EF92 on a Mullard CV131. So some tubes will have additional markings & codes to that of the actual maker, I suppose that if a replacment/equivalent tube was seen to have the 'expected' code from an alternate brand on it, then it may sell better.

To the question of the characters (MA, WB, WM) near to the Mullards '6CQ6' code on the CV's.. The characters usually are different, think of the characters as factory batch, group or lot numbers from manufacture. Sound isn't different.


Quote:
Originally Posted by vcoheda View Post
I don't know what all the coding on the tubes mean, but if a tube has the same brand (for example, Mullard) and number (CV131), I bet it sounds pretty much same, despite the presence of other coding.

Maybe someone else can chime in here.
From what ive worked out, the CV codes were introduced for the military/government. Phillips, JAN and Mullard made a lot of tubes for them but not many were labelled with their logos. Some tube packaging can also have codes that refer to other brands printed or written on them. This military symbol is that of three vertical lines that join at the top as so..... /l\ ....but please note that if a tube does have this symbol on it with other codes it does'nt necessarily mean its a 'Military Issue' tube but simply the makers way of saying its an equivelant.

Below is a list of makers code markings found on the actual tubes not the boxes. Each tube is grouped with its 'equivelants'. I assume that as Mullard made both a CV131 and CV4015 that it's highly likely that companys such as Westinghouse or Marconi’s Wireless Telegraph Co. etc, could have produced both types also. There are Lots of other brands which are not included on the list as I can't verify the markings ( that's for a future post )


Driver Tube Codes - Lettering as found on Tube

Military /l\ (Mullard) ----- CV4015 6065
Mullard ----------------- CV4015 M8161
Westinghouse ----------- 6065
Military /l\ (Mullard) ----- CV131 6CQ6
Mullard ----------------- CV131 6CQ6
MWT ------------------- W77
Ediswan ---------------- EF92
Brimar ------------------ 9D6
Sylvania ---------------- CV4015


Power Tube Codes - Lettering as found on Tube

- Only the first column of numbers is on the Tubes (in Russian) -

Svetlana ---------- 6C19П-B ----- (6S19P-V --- 6c19pi-B / 6c19ri-B)
Ulyanov ----------- 6C19П-B ----- (6S19P-V --- 6c19pi-B / 6c19ri-B)
Svetlana ---------- 6C19П ------- (6S19P --- 6c19pi / 6c19ri)
Ulyanov ----------- 6C19П ------- (6S19P --- 6c19pi / 6c19ri)
Beijing (China) ----- 6C19-J

edit:

The 6C19П is a small power triode used in some high-end amplifiers.
The Transcendent Sound T16 OTL ($3229 Tube Amp) uses 16 of these!
The WooAudio 4 - Single-Ended Class-A ($1150 Tube Amp) uses 2,
The REX VK-52SE ($10,000 Tube Amp) uses 4 of them,
But most importantly the LD2++ has 2 aswell!

This Link will take you to a simple webpage with a number of different tube boxes listed and pictured, another handy place for checking logos.
.
post #154 of 658
Quote:
Originally Posted by rain_uk View Post
Driver Tubes

Military (Mullard) CV4015 6065
Mullard CV4015 M8161
Westinghouse 6065

Military (Mullard) CV131 6CQ6
Mullard CV131 6CQ6
MWT W77
Ediswan EF92
Brimar 9D6
Sylvania CV4015
May i know where can i get those bold ones? I'd browsed vacumetube.net's price list and they only listed 6065 as $5 each. What manufacturer are those?

And is they any difference between Military tubes and normal ones? I just found out those EF92s on my LD2+ bears the "/|\" symbol. Does the military tubes more durable or what?
post #155 of 658
Thread Starter 
Quote:
Originally Posted by yrh0413 View Post
May i know where can i get those bold ones? I'd browsed vacumetube.net's price list and they only listed 6065 as $5 each. What manufacturer are those?

And is they any difference between Military tubes and normal ones? I just found out those EF92s on my LD2+ bears the "/|\" symbol. Does the military tubes more durable or what?
Please note that if a tube does have the /l\ symbol on it with other codes it does'nt necessarily mean its a 'Military Issue' tube but simply the makers way of saying its an equivalent.

Sylvania CV4015 and Westinghouse 6065 were obtained from http://www.vacuumtubes.net/ and look for 6CQ6 in their price guide. If you require specific brands then simply email them the details of what you require, I found their service very good. Im sure if they have the stock you'll receive them swiftly.

The Mullard M8161 were obtained from http://www.lichfieldelectronics or Here on their current eBay listing.

The Military /l\ (Mullard) ones (can also be JAN) were obtained via eBay and it was just by chance that they were Military Issue-NOS. I wouldnt expect them to be hard to find. 'More durable?' Well i've seen mention of it on the net, but to be perfectly honest the branded ones appear slightly better made, but my branded are also newer. As for them sounding different, well theres nothing much to mention between the branded Mullards and the Military, it depends more on how much burn in the valves have had.

As for the sound of the other 'CV4015-alikes', unfortunatly I dont know anyone else but myself that has the other ones at the moment (Vcoheda?). Still you can find my humble opinions of the Mullard, Westinghouse & Sylvania earlier on in this thread.
post #156 of 658
Quote:
Originally Posted by rain_uk View Post
6065's? Which ones.. One pair of Mullards I have (military stock) have 6065 and CV4015 on them, another pair of Mullards (branded) have M8161 and CV4015 on them, the Westinghouse only have 6065 on them, and the Sylvania have CV4015
I got my tubes today. I was expecting Westinghouse 6065s but got the Sylvania CV4015s. Not sure why they sent me those. I checked a box that said "no equivalents." I guess I should have specified "Westinghouse" but I figured since they were the only tubes labelled 6065, that wasn't necessary. Oh well. And yes, they do look cheap. I'll burn them in for a while before giving them a go. Who knows. Maybe I will like them.
post #157 of 658
Thread Starter 
Quote:
Originally Posted by vcoheda View Post
You like the 4015s as well. Am I the only one. I listened to them again tonight (30 hrs of burn in). The detail and resolution is there, but the detail is not lacking on the CV131s either. The 4015s sound overly bright. I even tried them with my 650s (as dark as they come) and I still don't really like them. Maybe more burn in or try another pair.

I feel like I'm missing out.
Something must be amiss.. The only CV4015 type that sounded poor for me were the Sylvania (using the HD650's). Clutching at straws but could it be an uneven balance with source/interconnects leaning towards the brighter side? I wouldn't normally suggest it, only you dont seem to be getting the best of these tubes (i'm assuming they are Mullards you're using). Perhaps they are a duff pair, perhaps the LD2++ has a fault? The thing is, with the equipment i'm using, I have never had them sound bright, harsh or anything but superb, and thats with only a days 'burn in' to start them off. With out any doubt, I have found that the Mullard CV4015 do certainly show up any poorly mastered or recorded music, giving a sense of the recording just lacking something, luckily all my music is on CD so its been just the odd disc. I have yet to try the CV4015 with the Svetlana 6C19П-B power tubes, when they arrive, I will let you know the outcome with those.
post #158 of 658
Thread Starter 
Quote:
Originally Posted by vcoheda View Post
Sylvania. Who knows. Maybe I will like them
I'll be surprised if you do!!
post #159 of 658
i just placed order on a pair of W77 and Mullard 4015s. Vacumetubes.net haven't reply my e-mail on the enquiries of Westinghouse and Sylvania tubes.
post #160 of 658
Thread Starter 
Quote:
Originally Posted by yrh0413 View Post
i just placed order on a pair of W77 and Mullard 4015s. Vacumetubes.net haven't reply my e-mail on the enquiries of Westinghouse and Sylvania tubes.
Lets hope they are what they claim to be...it can be pot luck sometimes!


So far i've managed to gather these as drivers,

1 Pair - Military Issue /l\ unbranded - CV4015 6065 (Mullard manf.)
3 Pair - Mullard branded only - CV4015 M8161 (2 pair still NOS)
1 Pair - Mullard branded also with /l\ symbol - CV131 6CQ6
1 Pair - Westinghouse branded only - 6065
1 Pair - Ediswan branded only - EF92
1 Pair - Sylvania branded only - CV4015
1 Pair - MWT branded only - W77

But theres a few more I want to hear if they come along, like the Brimar, Phillips, and 6F21, V884, VP6 (if are compatible)
post #161 of 658

COmpatible t

what are all the compatible tubes known for the little dot II++?
post #162 of 658
Quote:
Originally Posted by ttt3008 View Post
what are all the compatible tubes known for the little dot II++?
Check Here
http://www.head-fi.org/forums/showpo...9&postcount=10

And Here
http://www.head-fi.org/forums/showpo...4&postcount=77

Basically anything equivalent to EF92. Would in theory work. Be sure to double check if they are indeed equivalent.
post #163 of 658
Quote:
Originally Posted by ttt3008 View Post
what are all the compatible tubes known for the little dot II++?
Read this thread. If you own a ++, it is worth it. Lots of good information here from other owners.
post #164 of 658
i'm getting the tubes for my LD2+ lolz. Just curious to know how they perform compare to the stock EF92s.
post #165 of 658
vacumetubes.net replied my e-mail, and it seems that they only have Sylvania 6065s.
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