[Beav]

Got my MPX3, same config, last week. I'm using Sylvania 6bls7gt tubes in the back slots, and have been using the CBS 5687 tube in the driver slot. Just rolled a TungSol 5687 in there tonight...letting it warm up now. I've got ElectroHarmonix 6SN7s that I will try after getting to know the TungSol sound. After that I'm turning myself over to my NOS Tube dealer. He's a good friend, and knows his tubes very well. I am curious what MPX3 owners have found to be good combos with NOS tubes. Great amp by the way...I've been on the fence about headphones for awhile..and the amps I've tried up to this point have not changed my mind about long term pleasurable listening experiences with cans...I'm a speaker guy. This amp however is doing things with the AKG701's I've not experienced with the other ones. Killer sound, bass about as potent sounding as my speakers...well almost

And the staging of the sound, best thing I can think to call it, is wild. The instruments are coming from far off and up close, I've got stuff happening above my head, and down towards the lower neck area. Just perceptions of course; and very different to try and describe when your audio vocabulary is based around years of listening to high end speakers. New audio territory to explore...cool stuff.

 

[PFKMan23]

Hmm.. Good combinations depends on alot of things, epecially with the SP amps. If you've got what the OP has, I might try sometihng like a Sylvania 6sn7GT with the 6BL7GTs or that Sylvania 6sn7GT with 6BX7GTs. That could work well with the Tung Sol D getter 5687 as well. Personally I like using the 14n7 Tall bottle. To use those you'd need a loctal to octal tube adapter. That being said, the 6V equivalent octal is the Sylvania 6sn7GT I also like the RCA 12sn7GT (you'd need the 6sn7GT in your amp) with the above tubes because it is warmer, which is a trait that I like.

Given that you have the 701s, I'd try a Sylvania 6sn7GT with the Tung Sol D getters. You might also want to look into finding some Sylvania or Raytheon 5687s as well. You might also want to try the 6BX7GT which is a more neutral/cleaner sounding tube than the 6BL7GT and pair it with a nice driver tube.

 

[sacd lover]

Quote:

Originally Posted by Beav Got my MPX3, same config, last week. I'm using Sylvania 6bls7gt tubes in the back slots, and have been using the CBS 5687 tube in the driver slot. Just rolled a TungSol 5687 in there tonight...letting it warm up now. I've got ElectroHarmonix 6SN7s that I will try after getting to know the TungSol sound. After that I'm turning myself over to my NOS Tube dealer. He's a good friend, and knows his tubes very well. I am curious what MPX3 owners have found to be good combos with NOS tubes. Great amp by the way...I've been on the fence about headphones for awhile..and the amps I've tried up to this point have not changed my mind about long term pleasurable listening experiences with cans...I'm a speaker guy. This amp however is doing things with the AKG701's I've not experienced with the other ones. Killer sound, bass about as potent sounding as my speakers...well almost And the staging of the sound, best thing I can think to call it, is wild. The instruments are coming from far off and up close, I've got stuff happening above my head, and down towards the lower neck area. Just perceptions of course; and very different to try and describe when your audio vocabulary is based around years of listening to high end speakers. New audio territory to explore...cool stuff.

Hey Beav ..... there are many, many good combos.

Personally, I tend to like a good 6sn7 or equivalent (7af7/ 7n7 with adapter) as the gain tube driving either the 5687's, 6bl7gt/a or 6bx7gt's. I prefer 5687's on the outputs and I havent warmed up to them .... or hit the right combination .... for the 5687 as the gain tube. A good 6sn7gt will open up the soundstage even more.

I am using a ken rad 6/12n7 ( I have the 12 volt option and use the identical ken rad 12sn7gt) for gain and some black plate 6bx7gt's as the outputs on my new SLAM SE.

My Supra 392 uses a sylvania 7n7 tall bottle = sylvania 6sn7gt/vt-231 for gain with a pair of GE 6bl7gta's for the outputs.

The sylvania short bottle 1950's green label 6/12sn7gt (again I am using the a 12sn7) is another nice combo with sylvania 6bl7gt's on the SLAM SE.

The 6bl7gt and 6bl7gta sound slightly different with the 6bl7gt having a richer tone and with the 6bl7gta still rich but very slightly more open sounding. The 6bx7gt is noticeably different sounding having a leaner and extremely neutral character. The 6bx7gt is probably the airiest sounding of these three tubes. But you need a warm sounding and/ or bassier gain tube to get right balance .... well atleast I do for my preferances. All these tubes sound far better run at 400-425 volts. The 6bl7gta sounds horrible at 300 volts but may be the best balanced tube of the three at the higher 400-425 voltage.