Little Dot Tube Amps: Vacuum Tube Rolling Guide - Page 27

I've tried some M8161 tubes (EF92) and i'll second that they're worth trying for sure.

how important is it to get a matched pair with tubes? also how big is the difference between ef95 and ef92 tubes?

Quote:

Originally Posted by RAZRr1275 

how important is it to get a matched pair with tubes?

Very, very important RAZR, if not the tubes don't work...lol...Just kidding of course...

I asked myself that question over and over for several years until I broke down and purchased a tube tester about three years ago...The short of it is- If one tube tests very very low and the other very high, the former will die out first and in the process bringing some channnel imbalance.  If both tubes have significant levels of juice it will not be noticeable.  Of course I'm talking about same brand, type etc....

That being said, I usually buy matched pairs because that's how they usually sell them.  I have also purchased various lots with a variety of tubes and have liked to match them myself when at all possible, which was a lot of fun..

In reference to other tubes, I posted in the I+ thread, there are many variants to choose from the different families.  See if you can get some 403As, CV850s, 6096CT...One of my favorite Grado tubes is the CBS Hytron JHY-6AK5.  Nothing harsh just smooooooothness....As was stated as well, EF91 & 92 are slamming as well...

I have just tried a pair of PSVANE 12AT7s on my LD VIIISE.  These babys blow the supplied ElectroHarmonix out of the water.  Not cheap at around $90 for the pair though.

Quote:

Originally Posted by mordy 

Based on my personal experience and those of others on this blog, the 6N6P power tubes will help driver tubes sound less bright in the upper frequencies, compared to 6N6P-i.
 

Hi Mordy, just wondering if you have compared the 6N6P power tubes with the 6H30Pi and if you have, is there any other difference aside from sounding darker? From what i gathered in the thread i concluded that 1) 6H30Pi should be the best sounding power tube (putting aside the DR tubes) and 2) power tubes doesn't effect the overall sound too much. I'm wondering if my reasoning correct or that it changes with different tube combinations. Thanks a bunch!

Quote:

Originally Posted by nkoulban 

I have just tried a pair of PSVANE 12AT7s on my LD VIIISE.  These babys blow the supplied ElectroHarmonix out of the water.  Not cheap at around $90 for the pair though.

Any caveats? i.e. abnormally high heat, strange gain difference, etc?

I know with my M8161's the gain seemed to drop a bit, nothing to warrant not using them just a noticeable difference in volume.

found some here: http://www.ebay.com/itm/Pair-Matched-PSVANE-12AT7-T-Vacuum-Tubes-/220809256839

Probably won't be able to get them for a week or two. I was actually looking for an upgrade to the 6H30PI tubes without having to spend $200+ on DR tubes.

Categg, I have only compared 6N6P (gold and normal) and 6N6P-I using a AKG Q701. In this combination, however, the sound impact of power tubes is noticeable. I am not going to use 6N6P with this headphone anymore. Before using expensive tubes, it is an affordable experiment.

No noticable changes going from the EH drivers to the PSVANE drivers (In gain, heat, etc)  What I got was more detail, better sound staging, instruments sounded more real and immediate yet I still had a touch of tube warmth.  Quite an improvement in my experience over the EHs and I did not need to muck about with NOS tubes.  As I said, you do pay a premium for this.  A friend of mine who has a Zana Deux amp subjectively felt that the VIISE with the upgraded tubes was on par.  We will be looking to make a proper comparison when we get the chance.  My only caveat with the LD amp I have is that the finish on it is ok, but not great, then again you are not paying top dollar for it either.

Hi Categg,

I have not tried the 6H30Pi power tubes so I cannot speak from personal experience. Based on reading blogs on this site my impression is that they are better than the standard 6N6P power tubes, but not by much, and for those who spent the money on the DR versions, the minor further improvement was not worth the extra expense over the 6H30Pi tubes.

As with all tubes, different equipment responds differently to the various tubes, and each person has to try what works for them and what they are happy with. That said, if you choose from the highest rated ones you cannot go too wrong, and then it is a matter of personal taste. One area that has not been explored much is how various combinations of driver tubes and power tubes work, but most people seem to think that the power tubes only contribute to some 15% of the sound.
 

I really happy with my 6H30Pi tubes, when I have some spending cash I'll pickup some PSVANE tubes and give em a try. If there is a noticeable improvement over the 6H30Pi's then I'd say its worth it, as vague as that is :)

Agree with Mordy, in terms of SQ dependent of the whole chain of equipment and also the lack of experience with power/driver tube combinations.

Although, it seems that many people just live with 6N6P and haven't tried other power tubes. I would encourage to put the "15%" to the test.

how long do tubes take to burn in? i kind of splurged and got the mullard m8100, voshkod's, sylvania 408a gold brand, and ge jan5654w and would like to hear these at full strength as soon as possible

Thanks mordy and Acapella 11. I guess since i already have the 6H30Pi tubes as the stock tubes on my LD Mk IV SE i shall only consider swapping power tubes if i exhaust driver tubes options. 

Speaking of burn in. I stopped keeping tabs on my Telefunken 6AK5W after 200 hours of hoping that they would tame down the top end so it was a surprise when i swapped out my RCA black plate 5654 and popped them in for a friend of mine to listen to when he came over my house and found that the tube has tamed somewhat into thinner sounding but not as bright or punchy as before. I'm not too sure is this brain burn in or did the sound really changed...  Both me and my friend agreed that while it was still bright sounding it definitely didn't sound hard on the top end. 

Updated

Since the Mullard M8100 (CV4010) tubes are quite popular tubes (for a good reason), I am taking some time to share Mullard M8100 (CV4010) vs Sylvania JAN 5654W impressions.

I have just dug out my Mullard M8100 (no Mullard label, CV4010, KQDD/K) and compared them to the Sylvanias. Both are quite well balanced tubes. From the sound signature, the CV4010 is warm and the reproduction of the frequency spectrum emphasizes lower frequencies. The Sylvanias highlight the treble section more, produce less "tubey" mids whilst keeping a good bass presence.

Due to the warmer character and more forward mids, the Mullards engulf with an intimate and almost soothing sound, which can easily carry you away. I was ear washed by them, telling me, I am not missing any treble ;). The Sylvanias sound more analytical with their treble presence. This gives more metal feel to trumpets and sizzle on guitar riffs and also opens the space a bit more. Reverb effects become more apparent. The Sylvania's treble extension is relatively gentle such that it does not become fatiguing, just airier. Vocals appear not as seducing as with the CV4010 but more neutral / chiller. I guess the mids of quite a few tubes sound chiller than the M8100. In the bass section, Mullard wins as there is more bass feel. Sub-bass "surfaces" noticeably more. The Sylvanias still keep up very well, they sound a bit more on the mid bass side, which is punchy, and that is what gives these tubes an overall well balanced bass presence.

In summary, I like both :). Although both are good all rounders, they certainly sound different and as so often the choice is according to setup matching and preferences.

Quote:

Originally Posted by RAZRr1275 

how important is it to get a matched pair with tubes? also how big is the difference between ef95 and ef92 tubes?

I would just get the same type and brand of tube - preferably the same batch date.  I actually prefer a little bit of imbalance in the tubes since my right ear is weaker than my left.  I can get a more centered sound puting the stronger tube on the right side.  That's just my thing. I'm pretty anal about center imaging.  I think matching is more of a marketing tool to get more money from folks to be honest.

There's a big difference in soundstage with the EF92 tubes (wider) and even more with the EF91 tubes.  The EF91 tubes may distort on low ohm cans like Grado from what i read. No problem with my HD650s.