Tube Nube! Where to start,,

[audiobilly]

Can anyone give good starting pointers on what tubes are worth looking into for a phone-pre/line switcher unit? I am now an owner of a Conrad Johnson PV-7, and have no experience with what brand of tubes are worth starting with. I have searched on this forum for such, either my search wording is not cutting it, or this subject has not come up yet (HA) in the Analog Line Level section of this forum. I did not think it would be appropriate to post this subject in the "Amplifiers>Tubes / Valves" forum as this is not discussing a tube amp.

Trying to come up with a good starting point to roll tubes. Any reading material is also desirable!

Thanks gang!

 

[audiobilly]

Wow, nobody has anything to say about this?

Is there a problem with the thread?

 

[c2cthomas]

Hi Bill - I typed in "Conrad Johnson PV 7" into "advanced search" and quite a few things came up but they were pretty old threads.

BTW - David P. sez that you're gonna try to make the Nashville Audio Society meet at his place and I'm looking forward to getting to meet you.

 

[audiobilly]

Hay Tom, I was typing in "tube shootout" and "tube comparisons" and such. Per my limited understanding there are some preferred tube manufactures over others. Such as bugle boy over xyz. I have no experience with what tube manufactures are the ones to shoot for and the ones to stay away from. I guess I am not conveying the question correctly, or none wants to bother with it.

Yep-r, gonna make the meet. Look forward to meeting all involved and specially putting a face to you and Dave. See you there unless my world come crashing down that weekend!

 

[c2cthomas]

try this old thread. http://www.diyaudio.com/forums/tubes-valves/17681-conrad-johnson-pv-7-noise-2.html

Also some tube sites - such as bottlehead - might have more info.
Set Search Parameters

 

[audiobilly]

Thanks Thomas!

 

[vinylkid58]

For 12AX7's; Joe's Tube Lore

For 12AT7's, I don't think you can go wrong with NOS Mullard CV4024. JJ's are supposed to be good for new production.

What's in the preamp now, EH's?

jeff

 

[DF96]

There never seems to be much discussion of 'tube rolling' on this site. All it can do is check to what extent a particular instance of a particular tube design in a particular circuit at a particular bias setting (etc.) matches the preferences and expectations of a particular listener. This is why on those sites where rolling is more popular, people rarely agree on the outcome. They want to say X is better than Y, but in another circuit with a different set of ears Y may sound better than X. Perhaps an exception is noise, where some tube designs/manufacturers may be better than others.

A good circuit should not be too fussy about tube details anyway.

 

[SY]

For 12AX7's; Joe's Tube Lore

Is that site serious or a parody?

 

[DF96]

I make no representation as to how any of these tubes might sound in your system,

the risk of course is that one of those might ideally match your rig, 'cause with tubes you never know what's going to lock-in in any given system.

There is a system out there somewhere that's the ideal match for any tube. This is just a comment on a general tendency.

At least he tries to make it clear that he is just offering personal preferences. I bet there are people who quote him as a guru, though! (Especially those with a few valves to sell!!)

 

[c2cthomas]

The 1st time I heard about tube rolling I looked at my TV and thought "won't that make the picture upside down"...........

 

[audiobilly]

Have not cracked the case yet. Just got the unit this past weekend, in a inoperative state. Will get it running and then start to see what it sounds like. From there I want to try some other tubes to see what happens. I have read so much about how different manufactures of the same model tube sound differently. So I thought I would throw this out there.

Thanks for the info Jeff.

For 12AX7's; Joe's Tube Lore

For 12AT7's, I don't think you can go wrong with NOS Mullard CV4024. JJ's are supposed to be good for new production.

What's in the preamp now, EH's?

jeff

 

[audiobilly]

Thanks DF96,

I understand what you are saying, and I agree. At this point in my tube life/learning
experience, I am trying to find out if there was a good starting point. I hate to spend money on a tube that has already been found to be overall a bad experience, thus a waste of money and time.

There never seems to be much discussion of 'tube rolling' on this site. All it can do is check to what extent a particular instance of a particular tube design in a particular circuit at a particular bias setting (etc.) matches the preferences and expectations of a particular listener. This is why on those sites where rolling is more popular, people rarely agree on the outcome. They want to say X is better than Y, but in another circuit with a different set of ears Y may sound better than X. Perhaps an exception is noise, where some tube designs/manufacturers may be better than others.

A good circuit should not be too fussy about tube details anyway.

 

[c2cthomas]

Well - this isn't tube rolling - it's about tube testing. Buuuuuuuut seeing as how you are new to tubz it's worth a read.

RadiolaGuy.Com : Mutual Conductance vs. Emission Test
RadiolaGuy.com : Sonny's Tech Tips

I am aware of the fact that you are not entirely new to this stuff - but thought this info might be of some help.

 

[audiobilly]

Thanks Thomas, Any good reading is always appreciated!

I have been using the works of John F. Rider as references. I really like the way he comes across!

 

[audiobilly]

Thanks Jeff,

Some good reading, and I must say a good "informed" starting point. At least not going in blind! Just what I was looking for. Gonna continue to try to find this type of information and continue with a overall outlook with all the info that I can find. Thanks again!

~Bill

For 12AX7's; Joe's Tube Lore

For 12AT7's, I don't think you can go wrong with NOS Mullard CV4024. JJ's are supposed to be good for new production.

What's in the preamp now, EH's?

jeff