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Post by James on Jul 14, 2006 10:46:22 GMT -7
I have played my maz 38 pretty hard for the past 4 months since I bought it. Startin' to sound a little "Brittle" Do you think el 84's can start to lose their sweetness in this short of time? Also, was wondering about bias on this amp. I understand that its self biasing.......does this mean I never have too re bias? I was thinking it might need its bias checked.
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Deleted
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Post by Deleted on Jul 14, 2006 11:27:28 GMT -7
Hi James, if you have been playing the Maz38 pretty hard for the past four months then I don't think it is weird that you are needing a tube change. I change out the tubes in my amps every four to six months with heavy playing. You never have to rebias this amp because it is self-biasing. All you need is a matched set of tubes. Pop in a set of output tubes and see if that makes a difference. Usually when I smell something fishy with my amp I replace the power tubes. They are usually the culprit.
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Post by billyguitar on Jul 14, 2006 12:13:33 GMT -7
New output tubes made a world of difference in my amp. Every time you play an EL84 they seem to lose a little something.
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Post by James on Jul 14, 2006 13:25:48 GMT -7
Yeah, I heard they are quick burnin' tubes. Thanks fellas!
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Post by guitarboy02451 on Jul 27, 2006 8:56:51 GMT -7
I've had mine in for over a year, never changed tubes yet... haven't noticed any differences... Still sounds as sweet as the day I got her.
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Post by billyguitar on Jul 27, 2006 9:41:01 GMT -7
After 6 months I changed my output tubes on mine and WOW what a difference! thicker, smoother richer (just like my wimmens).
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Post by Telemanic on Jul 27, 2006 12:56:24 GMT -7
Yeah, i think especially with an amp running in true class A, they just dont get a break. those little suckers run pretty hot too, ....good thing the doc put the fan in there ! The old AC 30's could notoriously eat tubes which were almost closed off from any cooling. I think if you spent for some nos 7189's they will last quite a bit longer, and have a little different flavor to em as well. I like them a lot, really strong tube!
I have to admit tho in most BIG bottle amps, i dont rush to change tubes. I know a lot of people are proponents of yearly bottle changes or whatever, and maybe in an old marshall that only sounds right with insanely high bias, you'd go thru tubes pronto, but IMHO many times it's unnecessary. I mean take NOS KT66's for example, they have a use life of like 11,000 hours or something !! That could parlay into MANY years of regular use. My Best friend is a local legend around chicago land, and plays a vintage Ampeg V-2 head with all of it's weird tubes, the outputs are the 7027a's, ... he plays EVERY fri. and sat. night, almost without fail, for the last 29 years!! And the amp has the ORIGINAL power tubes still in it !! And it has lost nothing!Hard to beleive, but true. Ive been runnin with him for about the last 12 years and can vouch personally for that time period. Now obviously ya gotta factor in how hard you run the amp, and for whatever reason the V-2 breaks up nicely at only about 10:30 on the volume knob, and if you've ever heard one it's about the loudest 60 watts you'll hear ! I guess my point is that i see so many, especialy younger players, thinking that they just should automatically change their tubes every 12 months or so, whether they really need to or not, when maybe the bias has simply drifted a bit, altering the responce. Yeah i know, the new tubes dont always have that same longevity, ... i guess thats why i may be in the minority, but i LOVE Nos power tubes.
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Post by billyguitar on Jul 27, 2006 13:17:57 GMT -7
I turned it down recently but a guy sold a real nice V-2 for $250. I just have no use for it. 30 watts is way too loud for me to use in the places I play.
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Post by Telemanic on Jul 28, 2006 0:23:32 GMT -7
Man, Those things have a big ole honkin signal come'n out of em, dont they! Mines in great shape, but its kind of a boat anchor, i just dont use it either. Funny tho, as loud and muscular as that head is, my friend uses it REALLY well, and it never hurts, .............. well, unless your sittin right in line with it, in a small club! It's definately "his" amp. His style and tone have melded so seamlessly you cant see the line. I hate to go on, but i cant heap enough praise on that amp, ....29-30 years, his V-2 has been rockin a stage, damn near every weekend , and has never missed a beat! $250.00, .....huh,.... man i mighta picked that up!
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Post by myles on Jul 28, 2006 15:49:43 GMT -7
On a side note .... on Brad Paisley's amps I think if you get Chad's take on this he will agree with me ..... I notice a difference when a new output set is changed after 10-15 shows. Figure 3 hours per show with soundcheck and all. 30-45 hours! How scary. Sure, they will go ten times longer with ease but after 50 hours I think almost any set of ears will hear a difference. In a Vox AC-30 it happens even a bit faster due to poor air circulation.
But don't panic. There are folks that have months of hard use on their tubes. Michael Burks must do at least 250 shows a year, plays hard hard hard and can go a number of months and he still sounds great.
You may want to post something in the Ask Buddy Whittington post and ask him how much time was on his old set of output tubes in his red MAZ Sr. before I changed them out. He may have told me but I do not remember. I do remember the amp sounding much nicer and fresher after we changed the output tube set.
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mikek
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Post by mikek on Jul 28, 2006 16:16:48 GMT -7
I'm curious about this Miles. Is this short EL84 life only seen on current production tubes, or do many of the NOS's suffer the same quick decline too?
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Post by myles on Jul 28, 2006 16:29:22 GMT -7
I'm curious about this Miles. Is this short EL84 life only seen on current production tubes, or do many of the NOS's suffer the same quick decline too? It basically is an EL84 trait in old or new for the most part. The JJ lasts very long, as long as any NOS for the most part or close enough as not to be a factor. The Ei's have a very short life as a side note. This is not a tube. It is an amp issue for the most part. Cathode biased EL84 amps in general are running the tubes at voltages far in excess of any design spec. Look at EL84's in an old piece of Hi-Fi gear such as a Scott integrated amp or some sixties era receivers or amps. The EL84's would last for decades. But ... this is the price one pays for great tone and touch response. I have one pure class A single ended 6V6 amp that I built. It's output transformer for a 8 watt or so amp is larger than the output transformer of a 50 watt Marshall. The amp runs plate and screen voltages about 50% higher than max 6V6 design spec! Only NOS tubes hold up. The JJ 6V6 will work but does not sound good in the amp. The amp eats NOS 6V6s at the rate of about one every five hours! But ... just like a highly tuned race car it sounds pretty spectacular. It was designed as a studio tool. The amp has been in the hands of Carl Verheyen for a number of months and you will be able to hear the end result in some of the songs on his new CD that is scheduled for September release. You will also hear a lot of SRZ-65 on that CD also.
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mikek
Full Member
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Post by mikek on Jul 31, 2006 12:41:29 GMT -7
Great, thanks for the info Myles!
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Post by ronzoni on Oct 1, 2006 14:17:46 GMT -7
Been quiet for a bit but listening all of the time. Great info from everyone. I was strugging with my 38sr. 2x10 and my LP trying to get a little more thickness and sustain without any pedals. Just me and the guitar's volume control. I run it with the volume and master dimed all of the time with an Airbrake. It happened so slowly that I didn't realize it at first, but after 6 months or so playing 10hrs. a week it was fading. I was losing overall fidelity and punch. I put a set of 84's in it and boom! Fierce. I gotta swap tubes out 3 or 4 times a year running it that hot, I guess. Go for it.
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