Suggestions on different tubes to try.

pearsall001

With the weather getting bad I'll have plenty of time to have some fun tube rolling. I never really got involved with it before but now is the perfect time. It's for my CAL Alpha DAC which currently has a pair of Amperex Bugle Boy's (12AX7). Now don't get me wrong here, I am very, very pleased with the DAC's performance with those tubes. Very musical, warm & quite relaxing to listen to. My objective is simply to try something "different" and come to my own conclusion on the listening differences.

I won't be doing this right away because I have the Empirical Audio Synchro-Mesh re-clocker coming hopefully before Christmas. Once it's here I want to let it settle in with the DAC that I'm familiar with. Then I'd like to try different tubes. I read (forget where) that a lot of guys like the 5751 tubes but another article said that CAL didn't recommend them. The article didn't explain why. Maybe you guys might be able to shed some light on the subject. I'm open to all suggestions.

Dawgfish

5751s have less gain than 12AX7s and may not be compatible based on that. That's too bad as a rule of thumb I prefer triple mica 5751s from various manufacturers over their 12AX7 counterparts.

All of the usual suspect NOS manufacturers are worth trying, it just depends on what you are looking for. If you like detailed and linear sounding tubes the German tubes such as Teles, Valvos, and the Yogu made EIs have you covered. If you like beautiful mids with lots of warmth, Mullards, early GE/Ken Rads, RCA, and Sylvania black plates are the trick. Tungsram are a sleeper 12AX7 with nice warmth and beautiful mids. Warm, but detailed 12AX7s include Tung Sol and Raytheon.

Is there a specific sound you are looking for? If so that can further help narrow down choices. In all honesty though, tubes are very system and synergy dependent, so these are general sound characteristics. In the end it will be up to you to try and see what sounds best in your setup.

heiney9

Oh Phil, I could fill pages (pardon the pun :razz:). Did you have a price point in mind? I will put together something short and sweet with my fave's and why I like them.

This will be fun!

H9

pearsall001

Dawgfish wrote: »

5751s have less gain than 12AX7s and may not be compatible based on that. That's too bad as a rule of thumb I prefer triple mica 5751s from various manufacturers over their 12AX7 counterparts.

All of the usual suspect NOS manufacturers are worth trying, it just depends on what you are looking for. If you like detailed and linear sounding tubes the German tubes such as Teles, Valvos, and the Yogu made EIs have you covered. If you like beautiful mids with lots of warmth, Mullards, early GE/Ken Rads, RCA, and Sylvania black plates are the trick. Tungsram are a sleeper 12AX7 with nice warmth and beautiful mids. Warm, but detailed 12AX7s include Tung Sol and Raytheon.

Is there a specific sound you are looking for? If so that can further help narrow down choices. In all honesty though, tubes are very system and synergy dependent, so these are general sound characteristics. In the end it will be up to you to try and see what sounds best in your setup.

What I have now with the Bugle Boys is a very "listenable" sound. Nothing overly pronounced just very nice & smooth across the board. I'm not trying to duplicate that, I want a "different" presentation to see how it shakes out in my system. I'm still wondering about those 5751's just out of curiosity to see how they do.

heiney9 wrote: »

Oh Phil, I could fill pages (pardon the pun :razz:). Did you have a price point in mind? I will put together something short and sweet with my fave's and why I like them.

This will be fun!

H9

Hey Brock, for starters I guess I'd like to stay under 100 bones for the pair. I'm sure there's good stuff out there in that price range. I'm sure you could fill pages & pages but let's not get too carried away here!!! LOL!!

Dawgfish

^^Gotcha^^ I would say a good place to start would be the Tung Sol gray plates (don't think they made a black plate 12AX7), Raytheon, RCA, and Sylvania black plates (look for mid to late 50s if you can find), and the early to mid 50s GE/KEN Rad silvery-black plate. The Mullard and Tungsram tubes mentioned above are going to sound somewhat like the Amperex tubes you are running now with some differences.

The Telefunken smooth and ribbed long gray plate along with the Valvo Hamburg 45 degree slant getter 12AX7s are all going to give you a different presentation than what you have with the Amperexes, but they are going to be difficult to find under $100 a pair. I have seen the Teles in that price range occasionally. I really like the smooth gray plate Telefunkens. They have the detail and extension in the lows and highs that Teles are famous for with a touch of warmth. EIs will get you similar sound and can be had in your price range when you can find them.

If the manufacturer recommends staying away from the 5751s, I would follow their recommendation unless you know of someone that has safely tried them in your DAC. Generally there aren't any problems with substituting a 5751 for a 12AX7 in most gear, but every piece of gear is different. I would be cautious unless you know for sure the 5751 types are a safe alternative.

pearsall001

Dawgfish wrote: »

^^Gotcha^^ I would say a good place to start would be the Tung Sol gray plates (don't think they made a black plate 12AX7), Raytheon, RCA, and Sylvania black plates (look for mid to late 50s if you can find), and the early to mid 50s GE/KEN Rad silvery-black plate. The Mullard and Tungsram tubes mentioned above are going to sound somewhat like the Amperex tubes you are running now with some differences.

The Telefunken smooth and ribbed long gray plate along with the Valvo Hamburg 45 degree slant getter 12AX7s are all going to give you a different presentation than what you have with the Amperexes, but they are going to be difficult to find under $100 a pair. I have seen the Teles in that price range occasionally. I really like the smooth gray plate Telefunkens. They have the detail and extension in the lows and highs that Teles are famous for with a touch of warmth. EIs will get you similar sound and can be had in your price range when you can find them.

If the manufacturer recommends staying away from the 5751s, I would follow their recommendation unless you know of someone that has safely tried them in your DAC. Generally there aren't any problems with substituting a 5751 for a 12AX7 in most gear, but every piece of gear is different. I would be cautious unless you know for sure the 5751 types are a safe alternative.

Thanks for the info. Do you have any particular dealers you like to deal with to share with me. From what I've gathered one can't be too careful buying these glass beauties.

Dawgfish

Upscale Audio is always a good place. They are not the cheapest, but their testing procedures are rigorous so you can be assured you will get good tubes and they will stand behind their product.

heiney9

Tung Sol gray plate is a good place to start for sure. And yes, they did make a black plate but they are extremely rare and hard to find. Look for older Tung Sol with D, Square or Horseshoe getter.

Another somewhat rare, excellent American tube is the CBS/Hytron 12AX7 gray plate w/D or Horseshoe getter. Look for mid/late 50's date codes as by the early 60's they were relabeling other manufacturers tubes pretty consistently. I am auditioning a pair from 1956 right now! Simply Superb!

Like this:
http://www.ebay.com/itm/1958-Date-Matched-Pair-CBS-Hytron-12AX7-ECC83-Gray-LONG-P-Fat-D-Vacuum-Tube-80-/121225664507?pt=Vintage_Electronics_R2&hash=item1c399cd7fb

I've bought from him before, he seems solid.

Another great tube is the Valvo (Hamburg) ECC83, short plate with 45* angled getter. Valvo did produce their own tubes while being a division of Philips, but after about 1962 or so, MOST and PROBABLY ALL Valvo labeled tubes were either made by Mullard-Blackburn or Siemens-Munich or Herleen Holland. There are exceptions in the ECC81 (12AT7) line of tubes, but the ECC83 (12AX7) I have yet to run across a Hamburg made tube after about 1961. So it is imperative you know the 2nd line of tube code starts with a "D" to know it is for sure a Hamburg tube, they are special.

They make a long plate version of the above the first line of tube code is mC, but dang those are rare and very pricey. The short plates are rare and pricey enough~

There is nothing wrong with the Valvo labeled tubes from other plants, just know they are the same as what you could already have with a Mullard or Amperex or Siemens logo.

Sylvania 3 mica gray plate or black plate 5751 with square or horseshoe getter is fabulous, simply fabulous. Look for late 50's or early 60's and avoid anything later than that as the really, really special ones are the early ones. But be prepared to pay a lot, unless like me you wait and hunt, wait and hunt, wait and hunt and finally get a good deal.

Those are just a few off the top of my head. If you need any assistance identifying tubes please let me know. I just did an Ebay search for CBS 12AX7's and a lot of them have GE markings on them. The link I provided above are the real deal.

Cheers

H9

erniejade

Upscale turned me onto some siemens 6922 gold pin for my cayin cd player. While I liked the early 60's mullard in the cd player the siemens gold pins seemed to be a better match for the cayin.

Tung Sol, I am running a set of late 50's in my preamp with great results.HUGE difference between them and the new production ones. I also tried a set of RCA 3 mical 5751 and while it sounded ok it was not a good match. It could be the AR preamp i have needs the higher output of the 12ax7 vs the 5751 so what the manufacture and dawgfish are saying is is probably right on to make it sound right. BTW Dawg and H9 are the ones that helped me to find the right tubes for my preamp. Listen to them!

I do still have the rca 5751 sitting here if you wanted to try them out and see what they do.

heiney9

Don't overlook the late 50's early 60's long black plate Raytheon 12AX7 w/ D, Square or Horseshoe getter. Especially nice are organ pulls (Conn, Baldwin, Wirlitzer) as they are specially screened for low noise and usually excellent, low noise versions.

However guitar players have caught onto these wonderful sounding tubes and stocks are drying up as is the price creeping up. These would certainly not break the bank and give you a different presentation. One caveat, not all organ tubes are Raytheon's so again due diligence is needed to be sure you are getting what you think you are getting.

H9

pearsall001

WOW!!! Dawg, Brock, & Ernie! Thanks for all the feedback...there sure is a lot of info to process. Being a tube novice I'll tread lightly & do some homework & figure out where to start. It sounds like all the recommendations are stellar & I couldn't make a bad decision. The proof is always in the pudding so to speak. Nothing like trying a pair & see how they sound. Then move on from there. Thanks again.