Originally Posted by nolla /img/forum/go_quote.gif 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
Looks like they're about 8% off from each other, it's not the worst I've seen but they may not be putting the 1% resistors in your LD amp to their full potential. I'm a fan of matched tubes as in my experience they make a noticeable and significant difference in soundstage and overall 'involvement' of the music, and like everything else in life, you get what you pay for in tubes too.
I can't decide which to buy. Anyone have any impressions or opinions? They look almost identical. Both have black plates and halo getters with green labeling.
Originally Posted by Dept_of_Alchemy /img/forum/go_quote.gif Looks like they're about 8% off from each other, it's not the worst I've seen but they may not be putting the 1% resistors in your LD amp to their full potential. I'm a fan of matched tubes as in my experience they make a noticeable and significant difference in soundstage and overall 'involvement' of the music, and like everything else in life, you get what you pay for in tubes too.
- DoA
Thanks for the info DoA! But aren't they fairly good then? I remember reading that the borderline for a matched pair was 5%? I'd presume that 3% more don't make a HUGE difference?
Although based on what I've experienced listening with and without the amp itself and with stock/M8100 tubes the differences truly aren't THAT amazing. I'm more looking forward to buying a new pair of headphones and see what kind of difference they make. But then again this is probably what head-fi is, even the smallest differences count. Difficult to say when you see me shopping myself to death @ yenaudio!
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.
This is just what this Dr ordered
I just got my 120 ohm resistors today
Thanks for the MK III disassembly/assembly tips and the mini review !!!! Well done
Broke (wore it out actually) my damn desolder tool today though
Originally Posted by JimSmiley /img/forum/go_quote.gif Is anyone rolling either of these tubes?
GE JAN 5654W
Sylvania JAN 5654
I can't decide which to buy. Anyone have any impressions or opinions? They look almost identical. Both have black plates and halo getters with green labeling.
TIA
I'd say give the Sylvania's a try. So far, they have worked out better for me than the GE's, in an "overall" sense.
They look to be the same ones I have, which should mean "excellent sound" from them.
Originally Posted by Penchum /img/forum/go_quote.gif 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.
Thanks for the kinds words and 100% agreed here, especially with those Mullards!
Quote:
Originally Posted by Pricklely Peete /img/forum/go_quote.gif This is just what this Dr ordered
I just got my 120 ohm resistors today
...
Broke (wore it out actually) my damn desolder tool today though
, off to Rat shack first thing Monday morning
Peete.
Hah and good luck, it's definitely a worthwhile change after you've found driver tubes you like.
Getting the board back in takes awhile too - use the butter knife again!
Originally Posted by Penchum /img/forum/go_quote.gif I'd say give the Sylvania's a try. So far, they have worked out better for me than the GE's, in an "overall" sense.
They look to be the same ones I have, which should mean "excellent sound" from them.
Thanks, Penchum. The Sylvanias it is, not the golds, but it's a start.
Originally Posted by JimSmiley /img/forum/go_quote.gif Thanks, Penchum. The Sylvanias it is, not the golds, but it's a start.
What is really cool, is that they sound extremely close to the "Golds" once they are matured for about 45-50 hours! The differences are so slim, it's almost not worth mentioning.
Originally Posted by Dept_of_Alchemy /img/forum/go_quote.gif Where did you find the Amperex PQ's?
I found them buried on a eBay vendors huge site. Was about 45 pages into various tube types when I stumbled across 2 pairs of E95F's and decided to take a chance on them. Boy am I glad I did. The downside is trying to find more of these types, very rarely have I seen others posted for sale. If you happen across some snap them up....they are fantastic tubes, I love them. They do everything well without emphasis on any particular attribute of the sonic spectrum. Near as I can fathom they have the wonderful bottom end of a great NOS Mullard, the mids and highs of the best mil spec gold label Sylvania round getter black plates and 3D presentation all there own, in their own league as far as that is concerned.
Well I updated my source a couple of weeks ago and the Mullard 8161 has become my favorite set of tubes. They have been in my amp for the past week and a half and I don't plan on removing them any time soon.
Furthermore....
I wrote a awhile back that the 8161s were a bit too airy for my taste when paired with my AKG k501s. Turns out that there are significant differences (at least larger than I imagined) between the small shield Mullard 8161 and the large shield military grade 8161.
They have the same sound signature but the large shield is just more authoritative throughout the entire spectrum. Neither pair is my absolute favorite with the k501s, that honor goes to the "russians", but the large shield 8161s are close enough to where I don't feel compelled to switch out tubes everytime I switch headphones.
Originally Posted by ciphercomplete /img/forum/go_quote.gif Well I updated my source a couple of weeks ago and the Mullard 8161 has become my favorite set of tubes. They have been in my amp for the past week and a half and I don't plan on removing them any time soon.
Furthermore....
I wrote a awhile back that the 8161s were a bit too airy for my taste when paired with my AKG k501s. Turns out that there are significant differences (at least larger than I imagined) between the small shield Mullard 8161 and the large shield military grade 8161.
They have the same sound signature but the large shield is just more authoritative throughout the entire spectrum. Neither pair is my absolute favorite with the k501s, that honor goes to the "russians", but the large shield 8161s are close enough to where I don't feel compelled to switch out tubes everytime I switch headphones.
Yes, yes indeed! This very topic (the two Mullard types) has been the topic of conversation going back to the LDII++ amps. DoA and I feel the same on this matter (we've talked about it) and many others like you have found out the same thing. There is definitely something superior to the full shield M8161's that is hard to put your finger on. It does exist though, and it's audible for most users. Perhaps it has something to do with the tougher build quality internally. We may never know exactly what it is caused by, but I would still recommend buying the full shield M8161 over the "OEMs" or half shields.
Also, I'm glad your source improvements have worked out great!
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
