ADA Depot - A Forum To Support Users of ADA Amplification Gear

ADA Preamps => MP-2 => Topic started by: Neal Saenz on May 01, 2015, 09:19:27 PM

Title: 7025 tube
Post by: Neal Saenz on May 01, 2015, 09:19:27 PM
Any experiences/reviews using this tube in the MP 2?
Title: Re: 7025 tube
Post by: rnolan on May 02, 2015, 01:35:53 AM
Not personally, what brand is it ? 7025 from what I have read is a 12AX7A the 7025 being a European designation like ECC83 (http://en.wikipedia.org/wiki/12AX7) (http://www.dougstubes.com/preamp-tubes/12ax7-ecc83-7025/ruby-7025-ss-hg.html).

IIRC Dente has done some tube rolling with his MP2, and I suspect MJMP may know something about them.

For myself, I had the original Chinese tubes in my first MP2 (I bought it new as soon as they came out, had to sell my MP1 rig to pay for it, not that it's far away, MikeB has it so it visits me once a week LOL). The original tubes lasted for years. I finally changed them to Boogie STRs (briefly, nice feedback but a bit 2D and broke up (in not a nice way) on the bottom E) now I use the Mullard long plates in all 3 MP2s. They really suit my playing. Plenty of posts about them in the Tubes section.
Title: Re: 7025 tube
Post by: Systematic Chaos on May 02, 2015, 02:16:51 AM
7025 used to be/is the MilSpec version of a special selected 12AX7 for lowest noise/hum/microphonics. Other than that they are identical to 12AX7/ECC83.
Todays common tubes are already engineered for the above mentioned criteria, so a V1 selected/graded 12AX7/ECC83 is nothing else than a 7025 or vice versa.

The closest current/modern production tube to the original Chinese "National" 12AX7 that the ADA MP preamps were designed around and came shipped with is the TAD RT001 12AX7A-C as this tube combines all the best and desirable bits and pieces of the Chinese 12AX7 revisions A through C
Title: Re: 7025 tube
Post by: rnolan on May 02, 2015, 04:28:29 AM
Hey SC, thanks for the heads up, the TADs seem interesting, your a bit of fan of the TADs ?? IIRC they came up previously in a conversation about how to get the closest to the original MP1/2 tubes.
Title: Re: 7025 tube
Post by: Systematic Chaos on May 02, 2015, 05:42:12 AM
TAD has some nice tubes....I personally don´t like the 12AX7A-C, but I also don´t like the original Chinese 12AX7s. But in terms of current production 12AX7s the TAD is the closest to the Chinese "Nationals" that were used in the ADAs.

I do however like the TAD 6L6WGC short bottle as that one doesn't sound as stiff but ways more complex than the normal Chinese/Shuguang 6L6GC (...which TAD also offers...)

My actual favorite current production 12AX7 typo is the Tube-Town E83CC
http://www.tube-town.net/ttstore/Tubes/Tube-Town/TT-E83CC-12AX7-V1::4674.html (http://www.tube-town.net/ttstore/Tubes/Tube-Town/TT-E83CC-12AX7-V1::4674.html)
My all-time fav however is the Blackburn Mullard ECC83, followed by a good selected RFT ECC83...but those are both NOS and go for top $$$  :(