New tubes and sounding much different, why?

[vvcv]

Hello folks,

Glad I found this forum and hello! I hope i'm not in the wrong forum to ask such a beginner question.

The title explains the gist of my confusion. About 8 months ago i purchased a Luxman MQ-88 uSE amplifer which I adore. I do appreciate it much more than my two ss amps, same make different models, which are considered some of the best (by a well known engineer/designer); and in conjunction with a tube DAC purchase, I am convinced the tube sound is for me. So, with the Luxman shipping with tubes that were listened to and picked by Luxman, I figured that I had the tubes that were, generally speaking, the best for this amplifier. From what I remember, this amp was designed around JJ tubes. Well, recently, (more out of curiosity than anything else, I placed an order for the two types of (existing) driver tubes -which are JJ 803 and 802s). I decided to try two Northern Electric tubes (2 12AX7s and 2 12AU7s) in addition to two tubes with the "The Tube Store" name (Preferred Series 12AX7s). I believe the latter tube is designed from a NOS Mullard tube that was/is highly recommended.

Well, I've got to say, with the NE 12AU7 in the amp., I noticed that the space opened up some, not a great amount but enough to instantly say "yep", that did something. A few days later, I put in the other Northern Electric (12AX7s) and was blown away. It was like an entirely different amplifier. I mean, i flipped and freaked and yelled "F***.. How"? I regrouped, and thought that that may be a characteristic of new tubes. I mean, maybe brand new tubes have more juice/power/something that puts life into the sound. So, I then put in the 'TheTubeStore' tubes (12AX7s) and the sound changed yet again. It did warm up, not as much as the JJ's but closer than the NE's. My first 20 hours of listening with the new tubes, I feel that I have the luxury of the 'expressive' side of tube gear and all the detail/resolution of the best SS gear in conjunction with ultra high quality DACs. Well, of course it's too soon to make any definitive decision on which sound I like better, but that's not why I'm here. As someone who knows nothing of tube make/manufacture sound, is there any other reason (aside as this being a 'new' tube thing) why the sound is so vastly different with a change of tubes? Will the same degree of change happen when I swap the output K88 tubes? Will the new tubes take some break-in time, and do they change much if they do? The driving factor behind my main 'why' question(s) is that I would like to have something to look into (technically speaking) to begin taking notes on the sound of different tubes and what technically may make them sound a certain way. I guess to help me make more educated decisions about my next tube purchase(s).

As an ex-musician, with destroyed wrists, I learned all about instrument timbre, tone, and how wood and craftsmanship can change the sound by great degrees. With this in mind, any degree of information you may be able to offer, regarding technical aspects to consider when looking at tubes, if you may offer any amount of a tubes tonal character, I would greatly appreciate it.

Thanks for taking the time to read this whole experience.

robert

 

[Lowrider75]

Hello folks,

Glad I found this forum and hello! I hope i'm not in the wrong forum to ask such a beginner question.

The title explains the gist of my confusion. About 8 months ago i purchased a Luxman MQ-88 uSE amplifer which I adore. I do appreciate it much more than my two ss amps, same make different models, which are considered some of the best (by a well known engineer/designer); and in conjunction with a tube DAC purchase, I am convinced the tube sound is for me. So, with the Luxman shipping with tubes that were listened to and picked by Luxman, I figured that I had the tubes that were, generally speaking, the best for this amplifier. From what I remember, this amp was designed around JJ tubes. Well, recently, (more out of curiosity than anything else, I placed an order for the two types of (existing) driver tubes -which are JJ 803 and 802s). I decided to try two Northern Electric tubes (2 12AX7s and 2 12AU7s) in addition to two tubes with the "The Tube Store" name (Preferred Series 12AX7s). I believe the latter tube is designed from a NOS Mullard tube that was/is highly recommended.

Well, I've got to say, with the NE 12AU7 in the amp., I noticed that the space opened up some, not a great amount but enough to instantly say "yep", that did something. A few days later, I put in the other Northern Electric (12AX7s) and was blown away. It was like an entirely different amplifier. I mean, i flipped and freaked and yelled "F***.. How"? I regrouped, and thought that that may be a characteristic of new tubes. I mean, maybe brand new tubes have more juice/power/something that puts life into the sound. So, I then put in the 'TheTubeStore' tubes (12AX7s) and the sound changed yet again. It did warm up, not as much as the JJ's but closer than the NE's. My first 20 hours of listening with the new tubes, I feel that I have the luxury of the 'expressive' side of tube gear and all the detail/resolution of the best SS gear in conjunction with ultra high quality DACs. Well, of course it's too soon to make any definitive decision on which sound I like better, but that's not why I'm here. As someone who knows nothing of tube make/manufacture sound, is there any other reason (aside as this being a 'new' tube thing) why the sound is so vastly different with a change of tubes? Will the same degree of change happen when I swap the output K88 tubes? Will the new tubes take some break-in time, and do they change much if they do? The driving factor behind my main 'why' question(s) is that I would like to have something to look into (technically speaking) to begin taking notes on the sound of different tubes and what technically may make them sound a certain way. I guess to help me make more educated decisions about my next tube purchase(s).

As an ex-musician, with destroyed wrists, I learned all about instrument timbre, tone, and how wood and craftsmanship can change the sound by great degrees. With this in mind, any degree of information you may be able to offer, regarding technical aspects to consider when looking at tubes, if you may offer any amount of a tubes tonal character, I would greatly appreciate it.

Thanks for taking the time to read this whole experience.

robert

Brands of tubes sound different due to the manufacturer's design, the tooling, the type and quality of metals used. Also, how tightly the tolerances of the tubes are; eg, how well the tubes test for voltage, leakage, noise.

These websites have info on different brands, tube types, and their sonic signature...
http://www.audiotubes.com/12au7.htm

https://www.audioasylum.com/scripts/d.pl?audio/faq/joes-tubes.html

 

[Lowrider75]

@vvcc,
Very nice amp, BTW. What speakers are you using?

 

[vvcv]

Brands of tubes sound different due to the manufacturer's design, the tooling, the type and quality of metals used. Also, how tightly the tolerances of the tubes are; eg, how well the tubes test for voltage, leakage, noise.

These websites have info on different brands, tube types, and their sonic signature...
http://www.audiotubes.com/12au7.htm

https://www.audioasylum.com/scripts/d.pl?audio/faq/joes-tubes.html

@Lowrider75

Thanks a lot for these two resources, exactly what I was looking for... information to dig deeper into.

Regarding the Luxman, thank you! Are you familiar with this Luxman design? I say design due to it, I believe, being a 2.0 of the MQ-66(?) that was well received in the 60's-70's(?). Sorry, should be working on other things right now and can't get the exact information for you. I'm curious because I'm currently looking for a pre-amp (luxman or leben). I've been looking for either to have a listen -i'm pretty nervous of spending the money and having the pre change the sound characteristic of the amp (in the wrong direction) and just wondering if you've heard a similar Luxman with a tube pre-amp and what it may have done to the amps sound. But, to get to your question. I have a pair of Omen Super Alnico Monitors and Falcon Acoustics LS3/5a. I recently took the amp to a local shop, and was able to listen to it with Klipsch La Scala speakers. It was fantastic. I closed my eyes and (i know it's cliche) but i felt that i was in a cello players practice room -of which I've been in many times. The sound was palpable and I had the impression i could reach out and touch the bow/strings. I could literally hear that texture (not to suggest that I can't with my speakers) but i guess, with the Klipsh, they were creating what it feels like being in the same room with a cello and its player -the sound can almost vibrate your spine. Yep, was something else.

Thanks again for the tube information!



robert

 

[denimhunter]

Hi
i am slightly confused about ur questions.
Did u use 12ax7 instead of 12au7 as driver tube in your amp? They have very different mu values. 12ax7 is 100 and 12au7 about 20. 12ax7 has considerably more drive so would sound more dynamic and extended.
Yes vintage tubes generally sound far better than new manufacturer esp compare to Chinese made ones. I have heard many 12au and 12ax7 tubes.
https://www.effectrode.com/knowledge-base/the-12au7-tube/
This site also have reference for 12at7 and 12ax7 tubes