12ax7 or 5751 choice

[hal1]

Hi,

I have cj pv10a and looking for two good 12ax7 or 5751
(with good mid range and soundstaging) for the phonostage.

Please your recommendation.

Cheers.

[jaymanaa]

Are you asking for recommendations, or to buy tubes? If the latter, you'd do better to post in the classifieds, if the former, GE triple mica 5751s are hard (if not impossible) to beat.:music:

[PakProtector]

hey-Hey!!!,
You may find the lower plate Z of the 5751 to upset RIAA eq-ing. Consider taking a measurement with both styles of tubes. It may also be that the disruption will be quite small or otherwise welcome...they are your ears, yes?
cheers,
Douglas

[Jack G]

As it turns out, Raytheon made good versions of both types of tubes. I have both the Raytheon 5751s and their 12AX7s (long black plates). They are very good-the 5751s are better in the bass, and have a HUGELY deep soundstage, while the 12AX7s are better in the mids. I'm using the 5751s in my EAR phono stage.
jack

[KentTeffeteller]

Hi,

Raytheons and GE Triple Micas are superb and consistent quality. By and large, any of the JAN 5751 tubes are excellent. Just make sure your unit can use them without circuit modifications.

[wizargoz]

5751's appear to be going high on the 'bay... :scratch2:

[Jack G]

5751's appear to be going high on the 'bay... :scratch2:
They are selling high everywhere now. Bought mine years ago. Good luck finding the Raytheon windmill getter 5751s these days.
Jack

[diamondsouled]

5751's appear to be going high on the 'bay... :scratch2:

I think part of the reason for this is that they are not only under demand by audio enthusiasts but with guitar players as well. We may well be witnessing the drying up of the last of the NOS 5751, triple mica black plated, tubes.

Hopefully someone like New Sensor will take up the initiative and begin to make a high quality reproduction of a triple mica, square gettered, black plated, 5751. There would definitely be a market for them if a company was to put out a quality product at a fairly reasonable price.

As for phono section 12AX7s, staying with the 12AX7 rather than going with a 5751 is best because of the high difference in gain which can throw out the RIAA-eq. In my system I do like the sound of smooth plate Tele 12AX7s but it is a matter of synergy with your other components. For some systems the Teles are too bright and a long black plate, GE, Sylvania, Raytheon, or RCA may be the ticket. You can usually find these tubes labeled for use in organs such as Baldwin, Conn, Lowery etc. and pick them up for a decent price testing as NOS. Mullard long plate ECC83s are lovely in a phono section as are Amperex bugle boys, Valvo, and Philips tubes of the same vintage. The price for these tubes though is unfortunately going through the ceiling. One good thing is that a high quality NOS preamp tube such as these can give you as many as 10,000 hours of service. That's a lot of listening, so they do pay for themselves, over time.

If you like doing research check out tubemongers library:

http://www.tubemongerlib.com/gallery2/main.php

There are great pics of many of the finest tubes ever constructed in this library which I have personally found very useful for correctly identifying tubes. Most of the manufacturers relabeled tubes from one another so keeping track of who actually manufactured a tube, in spite of what it is labeled as, is an interesting and long study.

Cheers

Lar

[dividebytube]

Sovtek has a 5751 that is supposed to be pretty good - I've never tried them out though. I was lucky enough to get a pair of Raytheon 'windmill getter' 5751s by buying them separately on 'that' auction site. I also used a pair of the older G.E. 5-stars with good luck. It should be noted that later Sylvania/GE came from the same plant and appear to be identical.

[gearhound]

As a 3rd-rate guitarist.....I prefer a 5751 (NOS Sylvania) over the higher gain Chinese-made 12ax7 that came stock in my 5 watt SE guitar amp.

Steve

[Mr. Lin]

I have a pair of JAN GE 5751s that's I've used a bit in my phono stage. It wasn't really long enough to give a good report, but I remember liking what I heard.

[Bruce221]

5751 can be a good replacement for 12AX7As-offer a bit less gain in the driver section can deepen the bass-and add a bit more headroom.