swampstomper
Full Member
The only thing that really worried me was the ether.
Posts: 136
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Post by swampstomper on Apr 10, 2019 13:48:58 GMT -7
I recently purchased a 2015 MAZ 8 head and it is a thing of beauty! I have a few questions. Is there a PDF version of the tube chart available? I would like to experiment with swapping tubes from my collection. What is the function of each tube position? I have spares for all the tube types except for the 12AU7/ECC82. What is the current recommended tube that I should look for to keep as a spare? I do notice a fair amount of white noise even when the volume and master are turned all the way down and some odd sounds when engaging/disengaging the standby. I suspect it is a tube issue. Is there a particular tube position I should be looking at first? The manual says the fuse should be a 1.5A 250v SLO BLO where as the amp itself says F 1 AMP 250v. Which fuse type is correct? Do I need to power the amp down when changing the pentode/triode switch? The amp came with an EQ bypass foot switch but is not variable boost. I have a variable boost EQ bypass foot switch. Would it be compatible with this amp? When experimenting with tubes I like to have the amp up on a bench away from the speaker cabinet. Is it safe to use a 15 foot 16 gauge speaker cable with this amp?
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Post by purpletele on Apr 10, 2019 15:20:25 GMT -7
I recently purchased a 2015 MAZ 8 head and it is a thing of beauty! I have a few questions. Is there a PDF version of the tube chart available? Check the webpage at Dr. Z
I would like to experiment with swapping tubes from my collection. What is the function of each tube position? That is not a fair question. Too long of an answer
I have spares for all the tube types except for the 12AU7/ECC82. What is the current recommended tube that I should look for to keep as a spare? Rectifier, EL84, 12AY7 & 12AX7
I do notice a fair amount of white noise even when the volume and master are turned all the way down and some odd sounds when engaging/disengaging the standby. I suspect it is a tube issue. Is there a particular tube position I should be looking at first? V1 & the Phase Inverter, I don't remember how many Pre-Amp tubes. Start at V1, then roll to PI, then you just keep rolling.The manual says the fuse should be a 1.5A 250v SLO BLO where as the amp itself says F 1 AMP 250v. Which fuse type is correct? Do I need to power the amp down when changing the pentode/triode switch? Turn the amp into Standby or turn it off
The amp came with an EQ bypass foot switch but is not variable boost. I have a variable boost EQ bypass foot switch. Would it be compatible with this amp? The Variable boost will work fine
When experimenting with tubes I like to have the amp up on a bench away from the speaker cabinet. Is it safe to use a 15 foot 16 gauge speaker cable with this amp? YesI answered the questions as well as I could. That amp might benefit from an upgrade. I think they are doing something different to the reverb circuit that helped with some noise, but I am not positive. I would recommend a direct email to repairs to discuss the upgrades they can do for the noise.
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Post by Faze on Apr 10, 2019 15:32:34 GMT -7
Congrats!
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Post by purpletele on Apr 10, 2019 17:10:16 GMT -7
Swampstomper,
I found that the Cream Alnico was the niceset speaker for the Maz 8 for my taste. It seemed to open up the amp a bit and made it more full.
That is a beast of an circuit. There is a tube driven FX loop and a reverb driver so that is 5 pre amp tubes.
My Maz 8 was a 2017 and was really quiet, I remember reading that there was an improvement to something in the circuit and it was much more quiet.
The amp is really nice, congrats.
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Post by dcarver on Apr 10, 2019 21:56:38 GMT -7
Hi Stomper, welcome to the Maz 8 community. Here's a link to the stock tubes from the Dr. Z website: drzamps.com/support/tube-info/ Scroll down to the Legacy Models. Here are the tubes I'm using in my Maz 8 : V1 - preamp tube - Tube Amp Doctor Select 5751 V2 - tone stack driver - new Tung-Sol 12AX7 V3 - reverb driver - new Tung-Sol 12AU7 V4 - reverb recovery - stock Sovtek 12AX7WB V5 - output tube driver - stock Sovtek 12AX7LPS V6 - output tube - NOS Russian 6p14p Transconductance # 20 from forum member Perry R. V7 - NOS 5AR4 (mislabeled 5V4GA) from KCA Tubes I highly recommend getting a couple 6p14p's from Perry R. One that breaks up at lower volumes, and one with a high Tc # for more clean headroom. My amp came from the factory with one. They sound great. Here's a link to Perry's Reverb page where you can get `em : reverb.com/item/17712408-dr-z-nos-6n14n-el84-power-tube-pair-for-your-dr-z-or-trainwreck-1980-s-vintage-glassYou don't have to buy pairs or quads. He sells singles. I've rolled quite a few tubes through my Maz 8. Check out this thread for more details on my results. ztalk.proboards.com/thread/80485/tube-rolling-maz-8Re: the noise issue : single ended amps pass any noise in the tubes, pedals, AC power, flourescent light 60 Hz hum, etc. straight through. There's no noise cancelling effect of a push-pull amp. Make sure you have no corrosion issues and all pots are good and snug. Below is a video from Dr. Z on periodic maintenance. Follow his recommendations and use good quiet tubes and noise shouldn't be a problem. My Maz 8 is Very quiet. BTW ... a 1.5A 250V Slo Blo fuse came stock in my amp. They work fine. Good luck. It's a great amp. Let us know how it works out. Cheers DC
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swampstomper
Full Member
The only thing that really worried me was the ether.
Posts: 136
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Post by swampstomper on Apr 11, 2019 1:27:47 GMT -7
Swampstomper, I found that the Cream Alnico was the niceset speaker for the Maz 8 for my taste. It seemed to open up the amp a bit and made it more full. That is a beast of an circuit. There is a tube driven FX loop and a reverb driver so that is 5 pre amp tubes. My Maz 8 was a 2017 and was really quiet, I remember reading that there was an improvement to something in the circuit and it was much more quiet. The amp is really nice, congrats. Thank you and thanks for your help!
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swampstomper
Full Member
The only thing that really worried me was the ether.
Posts: 136
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Post by swampstomper on Apr 11, 2019 2:01:36 GMT -7
Hi Stomper, welcome to the Maz 8 community. Here's a link to the stock tubes from the Dr. Z website: drzamps.com/support/tube-info/ Scroll down to the Legacy Models. Here are the tubes I'm using in my Maz 8 : V1 - preamp tube - Tube Amp Doctor Select 5751 V2 - tone stack driver - new Tung-Sol 12AX7 V3 - reverb driver - new Tung-Sol 12AU7 V4 - reverb recovery - stock Sovtek 12AX7WB V5 - output tube driver - stock Sovtek 12AX7LPS V6 - output tube - NOS Russian 6p14p Transconductance # 20 from forum member Perry R. V7 - NOS 5AR4 (mislabeled 5V4GA) from KCA Tubes I highly recommend getting a couple 6p14p's from Perry R. One that breaks up at lower volumes, and one with a high Tc # for more clean headroom. My amp came from the factory with one. They sound great. Here's a link to Perry's Reverb page where you can get `em : reverb.com/item/17712408-dr-z-nos-6n14n-el84-power-tube-pair-for-your-dr-z-or-trainwreck-1980-s-vintage-glassYou don't have to buy pairs or quads. He sells singles. I've rolled quite a few tubes through my Maz 8. Check out this thread for more details on my results. ztalk.proboards.com/thread/80485/tube-rolling-maz-8Re: the noise issue : single ended amps pass any noise in the tubes, pedals, AC power, flourescent light 60 Hz hum, etc. straight through. There's no noise cancelling effect of a push-pull amp. Make sure you have no corrosion issues and all pots are good and snug. Below is a video from Dr. Z on periodic maintenance. Follow his recommendations and use good quiet tubes and noise shouldn't be a problem. My Maz 8 is Very quiet. BTW ... a 1.5A 250V Slo Blo fuse came stock in my amp. They work fine. Good luck. It's a great amp. Let us know how it works out. Cheers DC Thanks DC. I decided to try track down the noise issue last night. I had a hell of a time getting the back panel off! It must have been put on before the glue was completely dry. The noise I’m hearing I would describe as white noise and I hear it even with the volume, master volume and reverb turned all the way down. I went through and tried a different tube at each position and while the noise seemed to change a bit it remained. It’s really not that bad and while I can certainly live with it I’d like to eliminate it if possible. I also notice a bit of hum in triode mode. I’m assuming this is normal. As far as tubes it did come with what I believe is a 6n14n. It was marked 48. I’m assuming that is the TC rating. At this point I’m leaning towards keeping a fair amount of clean headroom. I like a very clean base tone which I drive with a Suhr Eclipse dual overdrive. I’ve got some NOS RFT and Brimar 12AX7s as well as a few NOS Philips JAN 5751s. I’ll have to set a day aside to experiment with them. As far as the reverb driver, what was it you liked about the Tung-Sol 12AU7? Thanks again for all the help. I have a MAZ 18 2x10 combo which I love but I’m already pretty sure I like the MAZ 8 better. Great amp!
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Post by premiumplus (Dave) on Apr 11, 2019 5:45:54 GMT -7
Hey Swamp, welcome to Maz 8 land! It's a great amp, one of my favorite Z's.
I found that it helps to put a strip of electrical tape on the back of the amp where the rear panel mates up with the cab. Mine kept sticking every time I pulled it off and this fixed it.
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swampstomper
Full Member
The only thing that really worried me was the ether.
Posts: 136
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Post by swampstomper on Apr 11, 2019 6:06:50 GMT -7
Hey Swamp, welcome to Maz 8 land! It's a great amp, one of my favorite Z's. I found that it helps to put a strip of electrical tape on the back of the amp where the rear panel mates up with the cab. Mine kept sticking every time I pulled it off and this fixed it. Thanks for the tip! I really don’t want to go through that again.
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Post by dcarver on Apr 11, 2019 12:38:57 GMT -7
<< As far as the reverb driver, what was it you liked about the Tung-Sol 12AU7? >>
To my ear, the stock Electro-Harmonix 12AU7 reverb driver was a bit harsh with the knob above 12:00 or 1:00. The Tung-Sol seems a little bit smoother at higher settings. However, the difference is pretty small. I usually keep the reverb around 8:00 or 9:00 to get just a little ambient verb and use a pedal for real verb. That way it's very quiet.
With both volumes and the reverb knob all the way down, my amp is dead quiet. Where is the cut knob ? Turning the cut all the way up will cause a little hum.
48 would be a VERY high Tc#. I have a 6n14n w/ a Tc# of 20 in my amp, and I don't get output tube break up until I get the Master V above 3:00.
<< I also notice a bit of hum in triode mode. I’m assuming this is normal. >>
It depends on where the Volumes, Cut, & Reverb settings are. My amp is quiet in either pentode or triode mode until I start dimeing these knobs.
Have you tried plugging straight in, no pedals ? At one point I had some "always on hum". Went through all my pedals and snugged up the jack nuts. That fixed it.
Good luck.
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swampstomper
Full Member
The only thing that really worried me was the ether.
Posts: 136
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Post by swampstomper on Apr 11, 2019 17:15:41 GMT -7
Have you tried plugging straight in, no pedals ? I hear the white noise with nothing plugged into the input or effects loop and volume, master volume and reverb all the way down. It’s not loud, but I can hear it standing several feet away from the speaker. It’s certainly not a show stopper but I’d like to figure out what’s causing it. Thanks again for your help.
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Post by "Z" Steve on Apr 11, 2019 18:28:37 GMT -7
I have an 8 as well and love it. After rereading all the posts there is one item not discussed. Do you have a pedal to engage the EQ bypass? If so I'm curious to know if the white noise is louder or diminished when engaging and disengaging the bypass.
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Post by dcarver on Apr 11, 2019 19:46:59 GMT -7
Stomper, I checked my amp today. With both volumes all the way down and the other knobs at their usual settings, it's dead quiet ... like it's turned off. I have a feeling it's not tubes.
You may have an internal component that's out of spec. Possibly noise from the reverb tank or cables.
Is your AC power well grounded ? No fluorescent lights on ?
Now you got me wondering too.
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swampstomper
Full Member
The only thing that really worried me was the ether.
Posts: 136
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Post by swampstomper on Apr 12, 2019 0:46:17 GMT -7
I have an 8 as well and love it. After rereading all the posts there is one item not discussed. Do you have a pedal to engage the EQ bypass? If so I'm curious to know if the white noise is louder or diminished when engaging and disengaging the bypass. The amp came with the EQ bypass foot switch but I have not tried it yet. I will test as you suggested and report back.
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swampstomper
Full Member
The only thing that really worried me was the ether.
Posts: 136
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Post by swampstomper on Apr 12, 2019 0:54:43 GMT -7
Stomper, I checked my amp today. With both volumes all the way down and the other knobs at their usual settings, it's dead quiet ... like it's turned off. I have a feeling it's not tubes. You may have an internal component that's out of spec. Possibly noise from the reverb tank or cables. Is your AC power well grounded ? No fluorescent lights on ? Now you got me wondering too. I did test each tube position with a known good tube, so it’s got to be something else. AC power is well grounded to the best of my knowledge. No fluorescent lights. I’m using the same AC outlet and practice space that I’ve been using for years with my MAZ 18 and other amps without issue. I’ve emailed the Z repair department but have not yet heard back. Noise issue aside, man what a great amp. I’m having a blast with it!
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swampstomper
Full Member
The only thing that really worried me was the ether.
Posts: 136
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Post by swampstomper on Apr 13, 2019 3:21:39 GMT -7
BTW ... a 1.5A 250V Slo Blo fuse came stock in my amp. They work fine. I just pulled the fuse from my MAZ 8 and it says BUSS MDL1A 250V. This appears to me to be a 1A Slo Blo. My amp was built in August of 2015. I'm wondering if yours is an updated model. That might explain the noise issue and the difference in fuse rating.
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Post by dcarver on Apr 13, 2019 16:19:41 GMT -7
Yup, my amp was born in May of 2016. It came with the Variable Boost Foot Switch. I don't have any experience with a pre-update Maz 8. It may be that they have a little hum.
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Post by justjoshinya on Apr 13, 2019 18:26:53 GMT -7
My Maz8 is also post update and I haven’t heard any odd noises out of it? My Z Plus on the other hand which is also single ended does have some white noise type sounds that happen every now and then even with both volumes down, what I have noticed is after a couple strums on the guitar it goes away?
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swampstomper
Full Member
The only thing that really worried me was the ether.
Posts: 136
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Post by swampstomper on Apr 14, 2019 20:20:23 GMT -7
My Maz8 is also post update and I haven’t heard any odd noises out of it? My Z Plus on the other hand which is also single ended does have some white noise type sounds that happen every now and then even with both volumes down, what I have noticed is after a couple strums on the guitar it goes away? I’m hoping to get this amp updated for a few minor issues but as it is now it is the most satisfying amp I’ve ever played. Planning to gig it for the first time this coming Thursday night.
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Post by "Z" Steve on Apr 14, 2019 20:55:38 GMT -7
Depending on the size of the room you are rehearsing you can easily fall in love with the triode or pentode setting. Of course there's more volume in pentode, but triode gives up the goods sooner with a different feel. There is no bad choice with this amp! Write a review when it's over!
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swampstomper
Full Member
The only thing that really worried me was the ether.
Posts: 136
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Post by swampstomper on Apr 15, 2019 10:14:15 GMT -7
I heard back from the good folks at Dr. Z. I will be sending in my MAZ 8 head to be updated to the 2016 spec in May. I’m not looking forward to being without my favorite amp, but it will be worth it. Thanks again everyone for the help!
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Post by 195db on Apr 15, 2019 15:49:10 GMT -7
I heard back from the good folks at Dr. Z. I will be sending in my MAZ 8 head to be updated to the 2016 spec in May. I’m not looking forward to being without my favorite amp, but it will be worth it. Thanks again everyone for the help! That's why when I got my '13 I sent it in 2 days later. Didn't want to start bonding then be without it for few weeks.
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swampstomper
Full Member
The only thing that really worried me was the ether.
Posts: 136
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Post by swampstomper on Apr 15, 2019 16:56:40 GMT -7
I heard back from the good folks at Dr. Z. I will be sending in my MAZ 8 head to be updated to the 2016 spec in May. I’m not looking forward to being without my favorite amp, but it will be worth it. Thanks again everyone for the help! That's why when I got my '13 I sent it in 2 days later. Didn't want to start bonding then be without it for few weeks. It’s too late for me. I’ve already bonded. In a big way. 😀
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Post by premiumplus (Dave) on Apr 16, 2019 9:13:59 GMT -7
You're gonna love it. I'd never go back to the old 8 after having the modded one. The Master Volume change is truly spectacular.
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Post by dapa78 on Apr 16, 2019 10:58:13 GMT -7
Oh man, this thread is bad for me. Now I gotta reach out to good folks at Dr. Z to update my 2011 Maz 8..
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Post by zpilot on Apr 17, 2019 3:08:55 GMT -7
My MAZ 8 has a little white noise periodically. I'm sure it is because of corrosion or something in the switching contacts of the input jacks. I can plug/unplug several times and it goes away, for a month or so. It's annoying but not enough so yet that I feel the need to remove the chassis and clean them properly. Call me lazy.
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bzl
Junior Member
Posts: 61
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Post by bzl on Apr 17, 2019 9:12:51 GMT -7
My MAZ 8 has a little white noise periodically. I'm sure it is because of corrosion or something in the switching contacts of the input jacks. I can plug/unplug several times and it goes away, for a month or so. It's annoying but not enough so yet that I feel the need to remove the chassis and clean them properly. Call me lazy. Even just spraying some deoxit or the like on the plug before you do that will clean them a little better without any extra work.
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Post by zpilot on Apr 17, 2019 14:57:55 GMT -7
My MAZ 8 has a little white noise periodically. I'm sure it is because of corrosion or something in the switching contacts of the input jacks. I can plug/unplug several times and it goes away, for a month or so. It's annoying but not enough so yet that I feel the need to remove the chassis and clean them properly. Call me lazy. Even just spraying some deoxit or the like on the plug before you do that will clean them a little better without any extra work. It is the switching part of the jack. It can't be cleaned properly without accessing the inside of the chassis. You may think you are cleaning those contacts that way but actually you are just moving the crud around by plugging/unplugging the amp. It's a temporary fix. For cleaning the normal jack portion I use both a tool called a Conductool and a .25 caliber Nylon bore cleaning brush with contact cleaner on them. The Conductool is a fine abrasive shaped like a 1/4" plug. I don't think the Conductool is available any more.
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bzl
Junior Member
Posts: 61
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Post by bzl on Apr 17, 2019 15:01:48 GMT -7
That makes sense...if I understand, you are not getting clean the far back piece of you do what I said...is that correct ?
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Post by premiumplus (Dave) on Apr 17, 2019 17:57:48 GMT -7
Not exactly. In a switching jack you have two leaf springs the have a 'dimple' stamped on one of them. They are pressing together and closing the electrical circuit between them when there isn't a plug inserted. When you put the plug in, one of the springs is pushed away by the tip of the plug, which separates the leaf springs and opens the circuit. So you need to get inside the chassis and clean the 'dimple' part of the jack by pushing it open and spraying it, then putting a piece of paper in the contact, letting the tension grip it, and pulling the paper out. You'll see a black line on the paper...that's the crap that was causing the bad connection. I used to use a burnishing file to clean these contacts but they'll remove any plating very easily. A strip of paper is just abrasive enough to polish and clean the contacts.
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