Mullard CV4004

I have tried a matched pair in my DAC and found that they made the system sound indistinct. For example, Miles Davis' trumpet on Miles and the Jazz Giants sounded tubby and a wall of hiss arose around the music. Gillian Welch's opening notes on her most recent CD sounded grainy. Christa Ludwig singing Mahler sounded hoarse. And so on. I gave them a week, then they went into a drawer where they've stayed ever since. Sylvania, GE and Raytheon 5750s have worked much better for me -- more clarity, no tubbiness, and more quiet. Maybe I latched onto a bad pair because there are people who like these tubes--who knows? But at their price, I'm not eager to experiment with a new set.

Hi Masimong,

As a former owner of the PL2, may I suggest a few tubes options that made this amp sing. I did try the Mullard CV-4004 Ca. 1980's and found them rather boring so to speak. No real advantage over the stock 12AX7.

After speaking with a fellow Agon member who's opinion I trusted on the best tube for this particular amp..I found that the old 1950's RCA/Tung Sol Black plate's used in combination with a pair of Sylvania Labeled CONN 12AU7's also ca. 1950's was by far the most pleasing and life like sound I obtained from the PL2. These tubes gave the music weighty presence in the lower mids and a textural midrange with clean highs. If your interested in looking for them..Give Andy at Vintagetubeservices.com a try.

I purchased some CV4004s and found the same results as Zinfan2. However, just recently purchased a matched quad of Mullard ECC83 tubes from 1959 and these sound fantastic. Sometimes it all depends on who you buy them from. The vendor in CA I bought mine from and the most likely vendor you purchased your Prima Luna from sold me the set of Mullards I did not like (very microphonic and he wouldn't take them back). The Mullards are hard tubes to come by in excellent matched condition. More reasonable are the RCA 12AX7s from the '50s. Andy at VTS carries a good stock of them and can match them nicely to your amp.

If interested email me as I have some '62 Telefunkens that could be available.

If you really want the best 12AX7,
try the Amperex 12AX7, 7025 and the old Tesla ECC803S ( Telefunken copycat ) would be better choice.

...and don't forget the NP GrooveTube 12AX7M, an intended duplicate of a Mullard ECC83. They sure sound good in the frontend of my poweramps. Probably they'll be less expensive than the old ones recommended above.
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