Mullard Long Pates vs origional Chinese ADA tubes

[rnolan]

I'm posting this here as it is MP-2 specific (as opposed to tube talk in general), and there are a bunch of posts about it in the Tube threads.  But this wasn't a subtle difference, it was a big difference.

So I changed out the original tubes (Chinese ADA) from my NOS (well it's now getting used allot more) MP-2 the other night.
Some history, I started using the Mullard LPs years ago and fell in love with them (in my MP-2) any long time members will maybe remember the journey?.
I'd been enjoying this NOS MP-2 (which is now my live preamp), but the top end was quite brittle (and way more presence(y) frequencies), allot of edginess (2-6khz). Initially I thought it may be the brand new Lorantz speakers (happy to report that it isn't BTW).
So obviously this is extremely subjective, but the Mullard LPs just sounded so beautiful, all the harsh edges were gone, smooth distortion, warm, 3D, balanced freq response (low, mid, Hi)

12AX7s all sound different.  The new sensor Mullard LPs are the best I've used in a MP-2 by a country mile.

I started using the Mullard LPs a long time ago after trying Boogie SPAX7s (most likely JJs rebadged) as my first ever swap. And I'd forgotten how "big" a difference they make.

[Harley Hexxe]

Richard,

We all know how much you are enamored with long plate Mullards, and just as you mentioned that all 12AX7s do not sound the same, the same can be said about long plate Mullards. It depends on where you purchase them.

If it's a vendor who has a no-return policy on tubes, I move on. They are not tested and you have no idea how long any of their tubes have been in stock. They don't even open the tube box to be sure they're not sending you a tube that has suffered shipping damage and has leaked vacuum. Ask me how I know.

As for Mullards in the MP-2, I'm sure there are other tubes that will work as well. For example: One of my MP-2's has had a pair of original Wurlitzer 12AX7's in it for years and it sounds terrific, (Thanks Kim)! The other MP-2 has had a few different pairs of Mullards in it over the past few years, and the results have been mixed. So, they are inconsistent at best. I've put in a pair of Gold Lion tubes in it and got better clarity than the Mullards I've tried recently. These aren't long plate tubes, but not short plates either. I originally purchased these tubes for my MB-1, but they didn't sound so good there. I ended up with a pair of JJs in it for now until I find something better.

I'm still on the hunt for alternatives to Mullards. I'm just more selective where I get them from.

[rnolan]

Hey Harley, I going to have to change out one of the Mullards I put in last week.  It's in V2 and is a bit inconsistent.  It's the first dud I've bought here in Oz, I know they test them, this one works but fades in and out a bit (like very slow tremolo).  It's only affecting high gain patches (as it's V2).  I'm pretty sure where I bought them from have a return policy, down side is I bought 6 before the war started thinking the supply would be affected (as they are Russian made tubes) and I've only just used 2 of them, so I still have 4 spare, well 3 now LoL.  I'll send this one back to them but I'm not sure how they will react   as it's been a couple of years now.

It's a bit of a bummer because I've bought quite a few (~16(ish) IIRC) Mullard LPs here and they have all been fine and consistent. So now I'm up to 22(ish) and this is the first dud/disappointment.

Good to hear about the Gold Lions, I'll give them a try sometime.

[Harley Hexxe]

Richard,

  I do plan to get some from TAD and Doug's Tubes if he has any. I may also order some from Antique Electronic Supply in Az. I know they don't test them there, but I did talk with a guy there a couple of years ago, and he told me the truth about how they operate. They buy tubes by the pallet and just sell them, but if there is a problem with a new tube they sell you, they will work with you on an exchange.

[rnolan]

Update, the tube I thought was a dud has come good , after burning in with a bit of playing, it's now fine, go figure , I haven't had that before, they have always been fine from the get go.

Live rack now working beautifully .

[Harley Hexxe]

Great news Richard1

I'm glad the MP-2 was not an issue

[Kim]

Hey Harley, I going to have to change out one of the Mullards I put in last week.  It's in V2 and is a bit inconsistent.  It's the first dud I've bought here in Oz, I know they test them, this one works but fades in and out a bit (like very slow tremolo).  It's only affecting high gain patches (as it's V2).

Update, the tube I thought was a dud has come good  , after burning in with a bit of playing, it's now fine, go figure , I haven't had that before, they have always been fine from the get go.

Live rack now working beautifully  .

Just wanted to add that I've had that exact same problem one time after retubing one of my amps.  I asked the supplier of the tubes about it and they had good advice (that I'd forgotten about in this situation) so I pulled the tubes back out and cleaned all the pins and socket contacts.  That "fade in/out tremolo oscillate" problem never returned.  Obviously the tubes were new (and clean enough) but the socket contacts were not.    
May or may not be the solution to your specific situation Richard; maybe the voltage just cleared some gunk out of the way of the connections. lol 

[Harley Hexxe]

Hey Kim,


   A VERY good point, and I forgot about it too. I do it all the time with my tube amps, but it's true that the tube sockets in the ADA gear is old enough to need that attention too.

  Thanks for chiming in on this topic 

[rnolan]

Hmm maybe that was the issue .  But cleaning out the sockets can be problematic.  We had an issue with MikeBs MP-1 way back where I gave the sockets a spray clean and then had lots of issues with one of the tubes.  MJMP said at the time to never clean the sockets as it can make them worse and even cause shorting as dust mixes with the contact cleaner.  Maybe blowing them out with compressed air (if you can) is a better way to go?

[Harley Hexxe]

Hmm maybe that was the issue .  But cleaning out the sockets can be problematic.  We had an issue with MikeBs MP-1 way back where I gave the sockets a spray clean and then had lots of issues with one of the tubes.  MJMP said at the time to never clean the sockets as it can make them worse and even cause shorting as dust mixes with the contact cleaner.  Maybe blowing them out with compressed air (if you can) is a better way to go?

Richard,

Don't use a contact cleaner that has a lubricant in it. use a quick-dry type that will evaporate fast like Deoxit. You can also use compressed air to blow out any loose dirt or particles, but the trick is after you spray this into the sockets, you need to work the tube in and out to create a more solid connection.
You can also clean them out afterwards with isopropyl alcohol and wait for that to dry completely.

[rnolan]

Hey Harley, good to know .  I have a spray can of isopropyl alcohol which is what I use these days for cleaning.