A quad of real, honest to goodness Mullard XF2's, triple matched for emission, transconductance and current draw! It seems that I must have been slightly more nice than naughty this year...
3 posters
Look What Santa Brought Me!
kevco- Posts : 69
Join date : 2009-07-16
Location : Aldan, PA, USA
- Post n°1
Look What Santa Brought Me!
A quad of real, honest to goodness Mullard XF2's, triple matched for emission, transconductance and current draw! It seems that I must have been slightly more nice than naughty this year...
quadaptor- Posts : 60
Join date : 2009-05-04
- Post n°2
How Do They Sound
Please, by all means give us your impression of the tubes when you get the chance. I put up a thred on Groove Tube EL-34Ms the month before last as they are suppose to be faithful reproductions of the Mullard XF2 dual getter EL-34. I haven't yet written up my impressions, but at this time I will say they are some of the most precise tubes I've listened too - which includes Soveteks, Electroharmonix and Winged C EL-34s in a VTA modified ST-70; and, in a stock amp, whaterever I could get my hands on going back to the mid-80s when finding good tubes meant a lot of scrounging through electronic shops and the term "tube rolling" was scarcely heard.
Last edited by quadaptor on Thu Dec 29, 2011 2:22 am; edited 1 time in total
kevco- Posts : 69
Join date : 2009-07-16
Location : Aldan, PA, USA
- Post n°3
Re: Look What Santa Brought Me!
Please take a look at my previous tube rolling experiences with this amplifier first:
https://dynacotubeaudio.forumotion.com/t773-st-70-power-tube-shootout
I try to be as subjective as possible and purchased this quad to get as much amp time as I desired, not to let them moulder in a drawer, waiting to pass them on to my grandchildren...Impressions so far: They biased up easily and stayed that way. Their sound is "Very EL34", liquid midrange, dynamic highs, perhaps slightly muted bass...,slightly muted as compared with beam tetrodes such as KT66's or American type 6CA7's, not with other true EL34's. As these tubes were probably burned in before I was born, it's nice to not have to deal with that. As far as true EL34's go, I'll compare them to EH, Shunguang, and Winged C. They are FAR better sounding than all but the Winged C's and then perhaps we are in the same league at least. Maybe not better but different. Not as warm as the Winged C's, but warm none the less (if that makes sense at all)...Maybe it's time to put them up against Amperex XF3's or true Telefunkens...or better yet, Phillips metal base...(please send either or all to Kevco, courtesy of this site!) Honestly though, initial impressions are all positive after perhaps 8 hours of listening. Very very nice tubes and I was happy with the price. If you buy them or other old power tubes, please do yourself a favor and read up on power tube matching! Make sure you REALLY know what you're buying...When a seller says that they "all peg the meter at 114 out of 112 on my Tandy Junior Tubmite 3000, truly a matched quad!" Don't be so sure...This one makes me laugh:
http://tinyurl.com/cr4l5tm
He claims "matched quad", but goes on to state that after receiving payment for a minimum of $549, he'll have the tubes tested by the "world renoun Don Polito" before shipping...Say what? Who's this Don Polito anyway? Anybody else know of him? Why doesn't he test them before accepting payment? What's the seller going to say? Thanks for your payment sir, and Don Polito confirms that two tubes are shorted, one's gassy BUT the forth tests at 100%!
https://dynacotubeaudio.forumotion.com/t773-st-70-power-tube-shootout
I try to be as subjective as possible and purchased this quad to get as much amp time as I desired, not to let them moulder in a drawer, waiting to pass them on to my grandchildren...Impressions so far: They biased up easily and stayed that way. Their sound is "Very EL34", liquid midrange, dynamic highs, perhaps slightly muted bass...,slightly muted as compared with beam tetrodes such as KT66's or American type 6CA7's, not with other true EL34's. As these tubes were probably burned in before I was born, it's nice to not have to deal with that. As far as true EL34's go, I'll compare them to EH, Shunguang, and Winged C. They are FAR better sounding than all but the Winged C's and then perhaps we are in the same league at least. Maybe not better but different. Not as warm as the Winged C's, but warm none the less (if that makes sense at all)...Maybe it's time to put them up against Amperex XF3's or true Telefunkens...or better yet, Phillips metal base...(please send either or all to Kevco, courtesy of this site!) Honestly though, initial impressions are all positive after perhaps 8 hours of listening. Very very nice tubes and I was happy with the price. If you buy them or other old power tubes, please do yourself a favor and read up on power tube matching! Make sure you REALLY know what you're buying...When a seller says that they "all peg the meter at 114 out of 112 on my Tandy Junior Tubmite 3000, truly a matched quad!" Don't be so sure...This one makes me laugh:
http://tinyurl.com/cr4l5tm
He claims "matched quad", but goes on to state that after receiving payment for a minimum of $549, he'll have the tubes tested by the "world renoun Don Polito" before shipping...Say what? Who's this Don Polito anyway? Anybody else know of him? Why doesn't he test them before accepting payment? What's the seller going to say? Thanks for your payment sir, and Don Polito confirms that two tubes are shorted, one's gassy BUT the forth tests at 100%!
anbitet66- Posts : 143
Join date : 2009-12-23
Location : Valley Stream, NY
- Post n°4
Re: Look What Santa Brought Me!
Don Polito has a TV repair shop in PA.
http://www.manta.com/g/mmf2whl/don-polito
I don't know about "world renoun", but I guess he has a tube tester in the back (probably for one of them thar hybrid flat panels with the tubes in 'em).
http://www.manta.com/g/mmf2whl/don-polito
I don't know about "world renoun", but I guess he has a tube tester in the back (probably for one of them thar hybrid flat panels with the tubes in 'em).
kevco- Posts : 69
Join date : 2009-07-16
Location : Aldan, PA, USA
- Post n°5
Re: Look What Santa Brought Me!
Of course I mean no disrespect to Mr. Polito. I'd just prefer my tubes to be tested before I pay for them...