Does Changing The 12AX7 Tubes Make A Difference with In The ART MPA Preamp For Vintage GE Tubes
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- čas přidán 25. 08. 2024
- Take a modern ART MPA II dual mic preamp and swap them for a pair of classic GE 12AX7's and hear the difference with a mic and direct instrument sound. This also shows you how to DIY swap the tubes.
Each comparison should have been paired together.
I thought the GE’s were subtly warmer, smoother and sweeter. Less harsh in the mid range... the saturation is very musical. Thanks for ths video! 🙏🏼
I put a set of matched and balanced JJ tubes (12AX7 short plate) in mine. It was amazing. When I ordered my tubes from Eurotube, I requested the gain factor of the tubes to be 105 with a transconductance of 18 (I had experimented with several different specs and found those numbers to be best). Plus, since I ordered the short plate tubes, the microphonics were excellent (very low microphonics using short plate tubes). I also have GE tubes from the late 1960s that I tried (medium plate). Thank you for the great video. You are correct, swapping the tubes can be a wonderful thing. Overall, this microphone preamp is a great tool.
thanks for sharing that. its nice to get good sounding gear w/o spending a fortune for the last 10-20% improvement.
Found this while searching for a “how to” tube swap tutorial. Killer video man, top notch audio, video, editing, hat, etc. You know your stuff, +1 sub.
The overall character is still present, though the tube swap definitely smoothed and refined the upper limits of the gain. I think a modern TungSol 12AX7 which is the gainiest 12AX7 in existence and has great thick tone would be ideal for at least one channel where you can use the gain knob further and have a little more "oomph", leave the politer GE/RCA/Telefunken NOSs in the other channel
for DI, that could be quite good. for micing, might be adding too much color. try it an see :)
I have both the mpa 2 and the comp vla 2 both units are so clean sounding love it. Gonna try new tubes.
How long have you had them for. I do not wanna have issues like they are known to have. I am considering the Warm Audio WA73-EQ Microphone Preamp & EQ. Because I just wanna capture the sound I want into a clean capture device. For the price of it. It seems like it would be better to have than the ART mic and compressor pre amp.
@@eaglewarrior8707 I love the ART. Cuz it's so clean. But you can add color and saturation but it very clean. Exactly why I bought them. I didn't want to add cor just a clean signal. But like I said you can add color. I've had mine over 1 year so far
@@streetlogic and you haven't had these "issues" that the gentleman is referring to whenever they might be???
There it is!!!! Now you sound like you're really here😁 The new tubes are perfect!
Awesome, amazing difference thanks for the demo. Much more of a vintage thickness happening there.
Chinese Tube 01:35 vs. GE Tube 03:31
Switch back and forth to see if you notice any difference
A real A/B comparison with similar guitar sounds would be great.
When he got to changing them out I thought "oh no, I don't have a table saw, I can't do this!"
Just comparing your voice at the beginning and end is astounding. Good tubes = good sound when used right
RCA are nice . Popped a couple of the 1960s ones in my compressor nice bright clean lots of detail.
Great sounding demonstration. Thank you. :)
GE Tubes seem less harsh in the higher frequencies and much smoother and focused overall.
GE tubes sounded proper. Good video.
nice test, well done.
2:40 & 4:24 for DI clean
1:51 & 4:34 for stairway
I can hear a huge difference but that has more to do with your playing than anything. Try reamping next time for more accurate test please?
what do you mean by reamping ? test was done in the time it took to change the tubes out, shoot the process.
@@thedp Oh just that if they were exactly the same track reamped through both of the configurations, there would be no questioning whether the difference between takes is in tubes or your fingers. Also that way the tracks could be used to phase cancel each other for accurate analysis.
@@Zilbyfilms oh you mean playing a pre-recorded track thru the Art Pre... I've heard a few reviews that did that, but more work to set up :( not a bad idea but also subject to your initial recording & playback too. I think I was reasonably consistent on the playing part, nothing changed much between setups.
@@thedp depending where your fingers were, i noticed. on the stock one it had more rattle from the guitar. but listening back, i actually preferred the stock one since what you were playing was better with classic rock, i personally prefer OD over classical sounds but i think i'll be fine with the stock ones in mine.
It makes a different for shur. I record this one guy who should shallow and shrill .. Haha changed to some vintage tunes and his voice suddenly sounded super fat and deep. With the right microphone ofcourse
MAJORCOOL !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! GE SOUNDS SWEET !!!
I heard the ...... JAN Phillips 5751s tubes .....are good!
I think the swap sounds good for guitar and probably vocals. But I found the bottom was nicer in the first pair. I would probably prefer that for drums to beef up the bottom.
Thanks for the test. I have a MPII so I will change the tubes. But you could make a video, playing the same chords sequence and changin true time from one to another. So it will be more easy to ear the diference. Thanks
great idea but not sure I have the original media around anymore. it would require a re edit and of course I can't replace the video at this URL :( but I suppose I could post another vers but that could be confusing I think... I'll keep it in mind for the next time I do something like this.
Thank you so much for this
GE for the win!
camera on this channel is really good
1:35 vs 3:30 not a major difference, the stock valves are not that bad IMHO. GE tubes seems cleaner to me and more defined.
I can't really tell a difference, if I had to say what was different I would say the GE tube made the Guitar smoother.
That was the diff. The GE tube was smoother.
To my ears, it sounds like the stock tubes just need to be driven a little harder, for more overtones, and they'd be pretty similar.
Oh ya way smoother
Not sure if this changed with the newer versions but the unit I have has 12AT's in it not Ax's .. I did swap them out for Mullard's and Electro Harmonix's but they were the AT7's :)
interesting.. I actually checked the old tubes that were in this, had them in parts bin and they were marked 12ax7. maybe they changed the design a bit ? or got a deal on 12at7's that some one had a cargo container off and re-biased the circuit to work with them.
wow I have an incredible doubt to know which of the 2 pream is better if The Digital MPA ll Or The Art Pro MpA ll Please Let Me Know By I already have The Digital But I Want To Know Blessings
I think you'll find them similar.
Thank you for this video Steve!
Please help, I can not find any info on Mic Preamp Tubes that will be use only for Vocals.
Whats tubes would be good for Vocals??
I'm going for a full sound and smooth airy sound (Mariah Carey, Luther Vandross)
I just got the ART Pro MPA II and I'm going to change the stock tubes
Please any recommendation? thank you
these GE's are. however the mic will have the first and most important difference in any recording. tubes are more shaping transients, eq aka tonal shaping, gain and possible ( intentional ) clipping characteristics. some tubes can lend a bit of compression to the signal in their non linear gain response. look for a good mic - which doesn't mean super expensive either - first. this or other tube preamps can certainly help. it also greatly depends on the voice or instrument as some mics / preamp combos will work better than others. you have to learn your gear and pick / experiment a bit for the best combo.
@@thedp Thank you Steve for this great advice!
Nice info. Thx
Can I swap my Art Studio V3 tube? Which one do you recommend?
as long as its based on a 12AX7 sure or you find out what tube type is in there. there are other amp tubes, but this is one of the most common type in sound applications. the GE's are relatively flat - they don't over emphasize or cut freqs across the audio spectrum. other tubes may boost or cut or both giving them their characteric sound so I'd suggest looking for a tube that sounds like what you want and try it. there are tons of YT videos comparing tubes. Telefunken's are based on GE tech & designs but cost a lot more for what is basically the same sound.Also have you tried all the different settings on that preamp ?
You can essentially did what he did here, since its also a 12AX7 in there. Its pretty simple to swap out. If you search, you can find several mods for the V3.
Electro Harmonix 12AX7 from what i've heard , def have to check it out
Would you consider to try with 12ax7 groovetubes? i wonder what would be the result.
probably a more midrange sound. the GE's are pretty flat and designed to work out to a few MHZ. FWIW Telefunken is GE design / tech at 10X the price.
Hard to tell because there are larger differences in your playing which mar the results.
If you keep the 12AX7 type tube and it is not in OPEN GAIN design, then it should not make any change.
However, if you change it with a 12AU7 then the gain will drop, but the quality of sound will go up.
tube changes freq response. even between tubes of same type there can be differences due to bias adjustments. not sure what you mean by "quality will go up" since gentle distortion is something tubes due well and people kinda like.
Not really Steve.
The bias is setup in the local feedback resistors, called self biasing, in small signal tubes like the one we are talking about. The frequency response is also a function of the tube resistors and caps. None of this will change if the circuit was properly designed. The idea in good design is to make the resistor bias and frequency performance dependent on the the local circuit itself and therefore be immune to variations in tube construction. That is why I brought up the OPEN LOOP circuit which has none of these protections. Those will depend on the tube for the circuit's performance. (That is what a college education in electronic engineering will get you. I am an EE) So how swamped (their term) the circuit is will determine the performance as outlined above. Changing a 12AX7 with another 12AX7 of another brand, in a properly designed circuit, will make no difference at all. The proper designed circuit depends very little on the actual tube other than for gain. You might be thinking of POWER output tubes with their ability to have a pot for the bias setting.
There are a family of 9 pin tubes in the 12--7 tubes. These are optimized for either Grain or Power Drive capability. The 12AX7 is one of the worst in the family. These were made for cheap 5 tube AM radios. These can cut back on the number of tubes that are needed in the AM radio. This is called Economics. The 12AX7 driving a high Z load will still have a lot of distortion, but lots of gain. If you replace that 12AX7 with a lower gain tube with a lot of drive capability like the 12AU7 then since this tube can drive more power into it's load without distortion, this is what I meant by the quality will go up. This can be tested with an Analog Signal Analyzer. So the range of tube designs were meant to address these different requirements.
@@jimmoss9584 oh yes I know about the lower gain 12A_7 series. interesting idea to try a U7 instead. I've heard a few tube tests with various makes of X7;s showing more lows or mids or highs. The GE NOS / telefunkens tend to be even. I know some of these tubes are supposed to rated out to several MHZ but never investigated why audio would show this variation, unless the supporting circuitry is theoretically intentionally less than ideal design, then does let you play around with different tubes for different sounds. I initially bought this out of a semi-famous artist's studio with the stock Chinese tubes in it and was suprised they hand't of played around wtih it.
I also realize that the input loading could also change the sound, this preamp having impedance adjustment dial which so far only seems to make a fairly small difference, even with a ribbon mic. These days I haven't used it much havjing changed audio interfaces yet again which sound a bit better than the old ones.
Try to keep this in mind. That preamp company ART, they make junk. Junk = Affordable. Google "cheap ass Mackie audio consoles". I knew Mackie. We talked about his requirements many times. His goal was to build consoles that musicians could afford, not recording studios. The same thing goes for ART. If you know anything about consoles you would never compare a Mackie to a NEVE. Same goes for ART. What did this ART preamp cost you? I see they are about $300 or so. A REAL vacuum tube mic preamp will cost you about $4,000 to $5,000. These are PRO AUDIO mic preamps. In these, the entire audio path is vacuum tube. This means not one stage, but all stages are high end tubes. Look at MosswareProAudio or D.W. Fearn. Those are the top of the line. There are no short cuts there.
I was skeptical. I'm not anymore. Thanks.
Hey!!! Thx for the video!! I really liked the video production! What camera did you use?
it should say, but this was most likely C300mk2
what kind of camera are you using for the video ?? very clean picture
thnx ! pretty sure I used C300 mk2 for this one
oh damn GE is good!
Art pro mpa 2, not 3.
Hello,
How many tubes are in this tool? Which tube would you recommend? noiseless model tube. Thanks
1 tube per preamp. it you want "noiseless" tubes probably aren't your choice of anything then. there are mods for this to replace the opamps, caps, resistors. probably overkill as there isn't much noise in the unit to begin with. even today's lower end gear is really pretty good compared to what used to be out there a couple decades back. the tube I used is pretty even freq response. others may have more gain, or emphasize lows mids or highs. the GE / Telefunken ( same thing made in DE ) are pretty nice.
❤
Have you tried westinghouse tubes.
?
Should I get the the GE 12AX7 for vocals or do you recommend something else? I only gonna be using this unit specifically for vocals. Someone in the comments if you know please lmk.
yes on the GE's for vocals
Steve Oakley thanks💯
You !!TUBE!! :)
What kind of op amps can be upgraded in the pro mpa ii?
there are a bunch of TL084's if I recall, but 84's are reasonably decent. 74's I'd replace with 84's or Burr-Brown type. at that point may want to look at caps and some metal film resistors too. Its really pretty clean so while doing an op-amp upgrade might be ok, disassembling the unit is major PITA to get the board out.
what type of camera do you use?
I think this was C300 mk2 from the look of it.
I need help I have the same one and when I turn it on is getting hot :( and I don't hear my voice in the microphone anymore please I need some help
tubes work because they get hot - they have a heating element in them. , thats good. as for the mic, no clue. no idea what mic, if if requires phantom power, if thats turned on, if the wire is good, if phantom power is good, if its a ribbon mic that may of been damaged by phantom power. try swapping mics, wires, make sure settings are good.
@@thedp yess that's buddy I got it thanks a lot
@@thedp thanks bro was my connection i put the wrong cable
The saturation was night and day
Do the tubes with the Jensen mod
input transformers ?
Night n day
Why is it clipping? Otherwise there ain't no difference
To be honest i liked the chinese tubes
Bro. oil from the fingers!!!!! where were you gloves???
for what ? tubes don't care, they aren't tungsten light bulbs.
Vacuum tubes don't run that hot. You are thinking of halogen bulbs. You're talking a difference of 200 degrees or more.
Chinese tubes sounded like the bridleness of a fortune cookie.
I couldn't stay past the out of tune guitar.
I got one of these units and could not get it to stop buzzing. I tried everything, so I sent it back believing it was defective and ordered another one. Guess what...same problem! This cannot be an isolated case. Either way I popped for a Warm Audio unit instead...and guess what...NO NOISE! Thanks for wasting my time ART!
if 2 units gave you a buzz, its a ground loop problem. they can be pretty hard to track down, but first easy fix is connecting the ground screw on the back to a known good ground. having 2 power circuits on different phases is a common problem.
@@thedp Thanks for the input...I bought a ground tester just to check my outlets and they are fine...so everything is grounded but still the buzz...and it's actually the typical low freq hum...which theoretically indicates ground issue. I am so frustrated with this I just have to take a break and reassess my problem. I held out an additional two weeks trying to solve this before returning the gear. I even got an IFI DC Blocker...no dice. Two Preamps and two compressors...The Warm Audio WM12 and this MPAII and Warm Audio WA76 and the ART PRO VLA compressor. The only one that wasn't noisy was the WA12...it's still here. My electrician is licking his chops to re-wire my whole house...that's not happening! Color me red.
@@stevend984 ground loops are more tricky than that. while good a plugin indicator says outlets wired ok, it won't indicate other related problems - grounds at different potentials on different outlets, neutrals which in home wiring is actually also tied to ground being at different potentials. in typical home wiring there are 2 hot legs of 120V at different phases creating voltage differences between them. When gear is plugged into each phase a ground loop can happen because the hots don't match. in modern switching power supplies this doesn't matter, but transformer based supplieds can still be vulnerable depending on design. its also very possible you have a XLR with ground and - wired swapped, or ground and +. I'd check cables carefully. one way of isolating is to take all cables out, and connect one at a time until the loop returns. at that point you found the source and can figure out the fix. likewise you can also power everything on and take cables out one at a time until it goes away. if you have hum with just unit plugged in, mic, headphones then its either the mic, mic cable, or power supply. its a tedious search, good luck and much patience to find it.
@@thedp Thanks for taking the time to reply on my issue. The first thing I did was check all my cables. But here's the deal...I only have two pieces of gear plugged in...My Tascam Model 12 and the ART ProVLA compressor, (which I tried two of) with same results. All told I went thru two ART VLA's, one ARTMPA, a WA12, and a WA76. Results...ART VLA's both had the same low freq hum, the ART MPA was just noisy (weird), the WA76 had white noise interference, and the WA12 was perfectly whisper quiet as it should be. Originally I ran the MPA thru the other units in an effort to isolate the problem but the other units consistently had the same problem with or without the MPA so I took it out of the mix for simplicity sake of troubleshooting. A good acquaintance I have at Front End Audio has made the same observations and today I am also even going to move my mixer to another room just to see if any change is noticed. Just a short back story, my home is a mobile home I bought last year and it underwent major remodeling including electrical. I oversaw, assisted, and was involved in the majority of rebuilding of my place. That said, I'm fully aware of the possibility that this place has some electrical interference issues, which can become a can of worms. Still in the process of getting the rest of my gear set up...keyboards and some rack gear, I have my mixer and computer and DAW working without issue. Which lead me to initially believe there would not be the electrical issues I am now experiencing that I have never had before. But everyone who has heard my story has pretty much said the same thing..."Yeah...this can be a problem"!
This guy did a good job of testing this topic:
czcams.com/video/VaO7MmghoqA/video.html
sounds like there is digital clipping goign on
not at all
@@thedp then why does it sound so bad?
@@chrischoir3594 what do you mean by sound bad ? sounds fine here, most other folks have been liking the GE tubes. IF you mean did I go for both clean and slightly over driven in the unit itself, then that is intentional to see how that sounds since pushing a preamp into distortion is certainly a sound thats done.
@@thedp It sounds cheap to me
@@chrischoir3594 pushing a mic preamp into distortion may or may not be your thing, and thats ok, but it is for some folks as part of the signal chain in recording. Running clean, I'm happy with this unit. there are some mods for lower S/N ratio in it, but outside of maybe changing the op amps out I don't think its worth it considering what it takes to get this thing apart - everything has so come off / out.
Steve,
if you design a circuit correctly, the tube brand won't make a difference. The circuit is made to be in control, not the tube. The 12AX7 is the weakest tube out there. I would never use one in my designs. This argument is popular with guitar players. If you run a circuit in OPEN LOOP GAIN design different tube brands will make a difference, but OPEN LOOP GAIN design just sucks. This kind of circuit design, transistor or tube, leaves the circuit performance and sound totally to the tube where the tube can flounder around due to heat, vibration, because is is not controlled by the circuit. Have you looked at the HoneyBee vacuum tube mic preamp/optical limiter? This is a real tube mic preamp. It can be driven hard creating beautiful 2nd harmonics that warm up the sound. This is the only mic preamp I will use since 1997. It creates anywhere from a pure clean sound to a fat rich sound that is as big as a house. No OPEN LOOP GAIN designs in it... and no 12AX7s to be found in it.
I agree, the difference, if any, is not worth the change.
sounds terrible with either tube
Di guitar rarely sounds good. Cabinets are essential imo
you are basing this on digitaly compressed youtube video lol. i own one its great on vocals and drums...i use the art trans y fett compressor for guitar.
Okay smart ass, what impecable preamp do you use then? Enlighten us 😀
No difference to me.. not worth no upgrade
2:54 - 3:15
1:23 - 3:31
That's about the worse guitar tone I've ever heard. Maybe its be cause you were recording directly into a camera but it's super harsh and brittle.
Yes definitly replace your tubes . That will make ALL the difference .
It can even make a bad sounding guitar sound like Jimi .
And your voice will be better than Frank Sinatra
Yes roll the tubes .