|
Post by jodyb0429 on Sept 24, 2009 12:07:53 GMT -7
Hi folks,
So I have had the Z28 for a couple of months now and it is a great amp. After the honeymoon period though, I am having a hard time with piercing brittle sounding high end. I have the Dario EF86, NOS 5751, and NOS rectifier. The amp has JJ 6V6's. I amp playing through a single Greenback. I play a strat with fender custom shop 54's, which are vintage spec alnico V. I know that low output Alnico V pickups are part of the piercing treble problem. My question is what should I try changing? Has anyone found the JJ 6v6's especially trebly/piercing? Should I spend the money for NOS 6v6's. Should I try a different ef86? I have heard the mullard or telefunkin is slightly warmer. Or should I look at switching pickups to some alnico II or some higher output A5's to warm it up a bit. Whatcha think? Thanks for the help.
Jody
|
|
|
Post by awesome on Sept 24, 2009 17:41:47 GMT -7
your tubes may have went bad. which one? you'll just have to swap new ones in until the problem tube is found. also its possible that your amp isnt biased right.
you should ask Myles what he thinks in the Experts section
or try a different speaker if you have one or can borrow one, or maybe some different caps in your guitar to see if that is the problem before you start buying new pickups
by the way, NOS 6V6s are $$$ and hard to come by
|
|
|
Post by fishman on Sept 24, 2009 18:48:45 GMT -7
perhaps a weber beam blocker would tame it down. Also, a different speaker may work as well...I like the RedFang in the 28. I have some NOS RCA's and I am running JJ's. I am also using a NOS bugleBoy EF86...but, again, I don;t notice alot of difference from the stock 86 that came with the amp. I do however have a NOS Mullard rect installed....now that made a difference that was instant and easy to hear. of course, YMMV
|
|
|
Post by iceboxcity on Sept 25, 2009 7:27:18 GMT -7
I play a '69 tele through a Z28 2x10 and I definitely find it a little on the brite side - though i am aware that the guitar is responsible for the lions share of this. Any time I see a picture of a Z28 on the forum (or ebay) i always zoom in to see the settings and I'm amazed how many people have the treble past noon. HB equipped guitars I assume.
I roll the treble back on both guitar and amp and all is well. By doing this I find the brightness of the Z28 is offset by the great bass response and tight bottom end it delivers, amazing for a 2x10. With a tele this gives you a lot more flexibility in the neck and middle position pickup selections. I'm adjusting the tone knob on my tele as i play all the time.
One thing I've always been curious about with the z28 is that the treble knob has a great deal more impact on the overall volume of the amp than the bass knob.
Any insight would be appreciated.
Thanks as always,
Iceboxcity
|
|
|
Post by awesome on Sept 25, 2009 12:18:11 GMT -7
the thing is i've played thru the Z 28 using several different strats, never had this problem.
hey Iceboxcity, i believe i remember hearing that volume increases in the higher frequency ranges are easier to hear than in low frequency ranges, can't remember why though. probably has something to do with how bass frequencies curve around objects while high frequencies bouce off
also, Jody, the Dario EF86 is known to be a very bright EF86, maybe consider some other brands.
|
|
|
Post by jodyb0429 on Sept 25, 2009 14:26:08 GMT -7
thanks for all the replies. I am ordering a weber bias rite and check the bias, maybe biased cold. Also gonna replace the power tubes as I dont know how old these are. I appreciate the advice. I would like to try a different ef86 but NOS ef86's are so dang expensive...prolly get one anyway Jody
|
|
|
Post by iceboxcity on Sept 25, 2009 21:03:16 GMT -7
I installed a Dario ef86 a while back and while I didn't notice the tonal changes some people have described it solved a microphonic problem I had.
Best, Iceboxcity
|
|
|
Post by jodyb0429 on Oct 4, 2009 19:22:11 GMT -7
well, got a NOS mullard ef-86 in the mail Saturday and played at full volume with the boys tonight. In a word, wonderful. Little darker and warmer than the dario and it made all the difference. Also took the direct drive along instead of the BB preamp and I liked the swap. Didnt want to quit playing tonight Jody
|
|
|
Post by upfrontguitars on Oct 16, 2009 10:12:34 GMT -7
I don't think of the Z28 as bright amp, at least compared to my Maz 18, but here is what I'm using.
I am also using the Dario EF86 and a NOS 5751 (RCA) and a NOS Rectifier. I tried using a Mullard Rectifier and the sound got noticeably brighter and a little louder. What I use now is a Philips NOS rectifier that I got from KCA Tubes (mislabeled 5V4GA). These sound really good and I also put one in my Maz 18jr. It has a lot more life and detail than the Sovtek or whatever comes stock in the amp.
I am also using groove tube 6v6 tubes that are rated "soft 1-3" by groove tubes. I have no complaints about these tubes and they are reasonably priced.
Now this may sound neurotic, but also look at your guitar and speaker cables. They can make a difference, and big gauge cables with lots of strands may seem like a good idea but they can add brightness and distortions. I am kind of sold on the solid conductor cables from Evidence Audio. To save money, I buy the stuff in bulk from Bestronics and build my own cables. They really do sound good, and is not a bunch of over-priced techno-babble like Monster Cable.
|
|
|
Post by upfrontguitars on Oct 16, 2009 10:16:46 GMT -7
You can do a perfectly good bias by downloading the instructions from the Dr Z website. All you need is a voltmeter, so save your money.
The Dr Z method checks the plate voltage, which should be 375V. When I put in new tubes, it was off by 5-7 volts and very easy to adjust.
|
|
|
Post by hymns on Oct 17, 2009 17:59:59 GMT -7
Get some nice RCA 6V6 VT-107A Blackplate power tubes and it might surprise you with the other changes.
|
|