[Dept_of_Alchemy]

Quote:

Originally Posted by ciphercomplete /img/forum/go_quote.gif I have both pairs. Both sound great with my Sennheisers and my Goldrings but the small shield version lacks "musical weight" when I use them with my AKG k501s, the notes seem to have too much float to them and are too light. The large shield version does not have this problem. Although I sometimes prefer the added airiness of the small shields when I listen to my Goldrings and Senns. Right now the only tubes I need are the Mullard 8161 large shield and the Russian 6ZH1P-EV.

I much prefer the shielded Mullard M8161 ones with my HD650 and MS2i actually.

 

[ScottieB]

Quote:

Originally Posted by Penchum /img/forum/go_quote.gif Up until this point, all 5654/6AK5 models we have run into that are Sylvania, regardless of age, that have the black plates and round halo getters, have a superior SQ to them. So, the hunt is on and the search continues. The 6ZH1P-EV Russian tubes are a "must have" for almost everyone. They are super special.

I actually picked up (what I think are) the 'russians' - the title of the auction said "VOSHOD mil-spec 6ZH1P-EV / 6AK5 NOS" is that them? Haven't tried them yet, still in initial burn-in. Is there any sort of guide I can read about the general differences between the various tube families (ie EF92/EF95)? I'm learning a lot but a simple general guide about the various families and their similarities/differences would be an interesting read I think.

 

[Pricklely Peete]

Hi ScottieB,

This thread is loaded with all the info you desire and then some......time to start reading...at least it's only 108 pages

Peete.

 

[ScottieB]

Hey Peete,

I assure you, I did read the entire thread (took me several weeks though, so maybe my retention isn't so great)! Maybe I missed it, but I'm really looking for a basic guide to the tube families compatible with the LD MKIII - like the general differences between EF92/EF95 etc. Also, and more specifically, I'm looking to see if the tubes I bought are indeed the "russians" everyone is talking about... I quoted above, but here it is again "VOSHOD mil-spec 6ZH1P-EV / 6AK5 NOS". Thanks again for all your contributions - I'm really having a lot of fun with this amp!

 

[Dept_of_Alchemy]

Quote:

Originally Posted by ScottieB /img/forum/go_quote.gif I quoted above, but here it is again "VOSHOD mil-spec 6ZH1P-EV / 6AK5 NOS". Thanks again for all your contributions - I'm really having a lot of fun with this amp!

These from Yen Audio are definitely the right ones.

 

[ScottieB]

Quote:

Originally Posted by Dept_of_Alchemy /img/forum/go_quote.gif These from Yen Audio are definitely the right ones.

Thanks, DOA - those are the ones I grabbed (from Yen)! Sweeeet... after a few more hours on my M8161s I will try these.

 

[Pricklely Peete]

Quote:

Originally Posted by ScottieB /img/forum/go_quote.gif Hey Peete, I assure you, I did read the entire thread (took me several weeks though, so maybe my retention isn't so great)! Maybe I missed it, but I'm really looking for a basic guide to the tube families compatible with the LD MKIII - like the general differences between EF92/EF95 etc. Also, and more specifically, I'm looking to see if the tubes I bought are indeed the "russians" everyone is talking about... I quoted above, but here it is again "VOSHOD mil-spec 6ZH1P-EV / 6AK5 NOS". Thanks again for all your contributions - I'm really having a lot of fun with this amp!

Yup those are in fact the ones

Mine are made in Novosibirsk factory. Voshod are quite good. They are a really dynamic,clean, well behaved tube from top to bottom. Perfect "Rock/Metal" tubes

The little dot forum has more info....have you been yet ?

All you really need to know is EF92 and EF95...then look for all the naming conventions of those types. There are lots of cross reference guides only a google stop away

Peete.

 

[dgbiker1]

I just stumbled on a new source for 6AK5, EF95, and EF92 tubes while I was looking for an enclosure for my new project
Tubes & Accessories
Pretty cheap, our tubes look to run $2.50-$5.00 for raytheons, hollands, sylvanias, etc...

 

[NikZ]

I have a very very noob question.

How do you remove a tube on MK III? Do I just pull it out straight?
I'm very new to this and the tubes look very fragile. I fear that they might break if I use too much force.

 

[JimSmiley]

Pull while rocking it back and forth a bit..not too much, just a little wiggle.

 

[Dept_of_Alchemy]

Quote:

Originally Posted by NikZ /img/forum/go_quote.gif I have a very very noob question. How do you remove a tube on MK III? Do I just pull it out straight? I'm very new to this and the tubes look very fragile. I fear that they might break if I use too much force.

Just pull while rocking back and forth, you won't break the tubes they're quite sturdy. One thing to watch out for is if you're inserting older tubes some of their pins might be bent and the bent pins might damage the sockets on the amp, so you would want to gently straighten the pins before inserting them.

Note it is very easy to damage a tube by bending its pins so it's possible to break a tube by doing this if you don't have the right tools.

- DoA

 

[JimSmiley]

Just got the GE 5 Star 5654s rolled in. Watch out CV131 there is new kid in town, and he is definitely a contender. Impressions later..

 

[dr dougie]

Hey all,

Been listening to my LD III with DT880s awhile and thought I'd throw out my experiences.

First off, I did the 120 ohm mod. It's not *quite* as bad as some describe if you pull the board out the back. I kind of discovered this messing around but my method saves you having to deal with the transformer wires! 1) Remove front plate and disconnect harness to volume pot. 2) Remove top screws (not transformer) and back plate. 3) Wiggle the board forward enough to remove 2 front posts for top screws from the board. 4) Wiggle the board out the back slowly and carefully. I used a butter knife to gently push wires around as I did this. You'll be able to get the necessary resistors at least 1" from the housing, this is enough to desolder and remove them, and put in the 120 Ohm ones with tweezers. I used 1 watt with no additional solder. Remember that this voids the warranty. The soldering is easy compared to getting the board in position!

So further impressions are with 120 Ohm cathode resistors.

The reason to do this is to replace the stock 6H6N-Pi with 6H30Pi tubes. See Penchum's LD III review for more. Note that the Mk IV and IVse have 120 ohm cathode resistors and 6H30Pi power tubes.

I wound up getting the electro-harmonix Gold 6H30Pi tubes, as the Mk IVse has. I will say right away that the difference with the stock tubes is subtle but the 6H30Pi are cleaner and more refined all around. They improve everything top to bottom with all my driver tubes and have made my LD III into a keeper from a "maybe". They get *hot*.

I did use the stock tubes with 120 ohm cathode resistors before the 6H30Pi's arrived. Little Dot does not recommend this and says they may make the LD III unstable but I had no problems with many hours of listening. As far as I could tell the resistor mod did not affect the sound of the stock tubes.

I previously mentioned that I tried 6CG7's as power tubes also. My first generic GE 6CG7s sounded bad, they got hot and I worried about the heater current being too high. I eventually got a batch of used Motorola 6CG7 and they turned out to be RCA black plates - nice! I have also now run these for many hours with the 120 ohm resistors and they sound very good. I like the forward treble of the big Russian tubes better so far but would definitely try more 6CG7s. I attached a photo of my LD III with the Motorola black plate 6CG7s and Sylvania black plate, halo getter 6AK5 for the heck of it. Hard to tell but it's on!

For driver tubes my top 3 so far are:

1) Ediswan CV138/6AM6/EF91 from audiowrx on ebay. These have the best vocals and midrange of anything I've heard so far. Despite bass being a hair loose and high treble a teensy weak I find I keep going back to these. I don't know why more people don't try them - especially for lighter, vocal and classical music.

2) Sylvania 6AK5, black plate, halo getter. Great all around tube.

3) Mullard EF92/M8161/CV4015. These are definitely up there but I feel the Sylvania's do everything these can do just a little bit better.

 

[Penchum]

Quote:

Originally Posted by dr dougie /img/forum/go_quote.gif Hey all, Been listening to my LD III with DT880s awhile and thought I'd throw out my experiences. First off, I did the 120 ohm mod. It's not *quite* as bad as some describe if you pull the board out the back. I kind of discovered this messing around but my method saves you having to deal with the transformer wires! 1) Remove front plate and disconnect harness to volume pot. 2) Remove top screws (not transformer) and back plate. 3) Wiggle the board forward enough to remove 2 front posts for top screws from the board. 4) Wiggle the board out the back slowly and carefully. I used a butter knife to gently push wires around as I did this. You'll be able to get the necessary resistors at least 1" from the housing, this is enough to desolder and remove them, and put in the 120 Ohm ones with tweezers. I used 1 watt with no additional solder. Remember that this voids the warranty. The soldering is easy compared to getting the board in position! So further impressions are with 120 Ohm cathode resistors. The reason to do this is to replace the stock 6H6N-Pi with 6H30Pi tubes. See Penchum's LD III review for more. Note that the Mk IV and IVse have 120 ohm cathode resistors and 6H30Pi power tubes. I wound up getting the electro-harmonix Gold 6H30Pi tubes, as the Mk IVse has. I will say right away that the difference with the stock tubes is subtle but the 6H30Pi are cleaner and more refined all around. They improve everything top to bottom with all my driver tubes and have made my LD III into a keeper from a "maybe". They get *hot*. I did use the stock tubes with 120 ohm cathode resistors before the 6H30Pi's arrived. Little Dot does not recommend this and says they may make the LD III unstable but I had no problems with many hours of listening. As far as I could tell the resistor mod did not affect the sound of the stock tubes. I previously mentioned that I tried 6CG7's as power tubes also. My first generic GE 6CG7s sounded bad, they got hot and I worried about the heater current being too high. I eventually got a batch of used Motorola 6CG7 and they turned out to be RCA black plates - nice! I have also now run these for many hours with the 120 ohm resistors and they sound very good. I like the forward treble of the big Russian tubes better so far but would definitely try more 6CG7s. I attached a photo of my LD III with the Motorola black plate 6CG7s and Sylvania black plate, halo getter 6AK5 for the heck of it. Hard to tell but it's on! For driver tubes my top 3 so far are: 1) Ediswan CV138/6AM6/EF91 from audiowrx on ebay. These have the best vocals and midrange of anything I've heard so far. Despite bass being a hair loose and high treble a teensy weak I find I keep going back to these. I don't know why more people don't try them - especially for lighter, vocal and classical music. 2) Sylvania 6AK5, black plate, halo getter. Great all around tube. 3) Mullard EF92/M8161/CV4015. These are definitely up there but I feel the Sylvania's do everything these can do just a little bit better.

Great mini-review!

Well done!
I agree that the 6H30Pi are cleaner and more refined all around. My driver tube properties "improved" as well.

If I had to put a percentage on the improvement, I'd say somewhere between 10-15% overall.

One thing I did notice was that the lower end improvement made a few of my driver tubes much more likable. As an example, the Mullard M8161's. They have nice bass when matched with the stock power tubes, but now have a more refined and powerful bass when matched with the 6H30PI power tubes! This was an unexpected benefit, especially for the driver tubes that were slightly lacking in bass. They now present a much more "full spectrum" signature, which I really like!!

 

[nolla]

In addition to my stock 5654's and the M8100's I bought from David, I just pulled the trigger on a pair of Sylvania 6AK5's. The price was so tempting and the seller had such a reliable feedback that I didn't really think much at the moment I clicked 'buy'..
Afterwards I began to wonder if I have just bought a pair of junk. How good are these tubes according to these test results? Are they even close of being 'matched'? The numbers don't tell me much. I paid a ridiculous 6€ including shipping (approx. $9 USD) of them, so at least it won't eat up my wallet..

valve 1 Ia = 13.5 mA & Gm = 6.0 mA/V
valve 2 Ia = 12.5 mA & Gm = 5.8 mA/V