New Genz Benz Shuttle 9.0 Sizzle and crackle problem

Flo'Daddy · #1 07-13-2010, 12:50 PM

My Genz Benz Shuttle 9.0 arrived yesterday from Musicians Friend and when I tried it out, I noticed an intermittent hiss, almost a sizzle and a crackle when running through my Aguilar 112 cab. This amp is literally brand new out of the box. This was at low volume; preamp knobs set at 12 o'clock and the master set at about 9 o'clock. Granted, I was sitting right in front of the speaker, but the sound (crackle) was intermittent and was happening with nothing plugged in to the amp input, as well as when I was plugged in.

I A/B'd the speaker and cable through the same power source with my Acoustic Image Clarus Series 1 and heard no excess noise from the speaker or cables using that amp. I also tried a different speaker cable with the GB 9.0 since the noise was there when no instrument cable was plugged in as well.

The sound was definitely intermittent...I posted a little on a different thread here and Musicman20 suggested I start a new one. He said he had a new amp that had a bad tube in the past (different amp).

I posted here on that thread and tried it again with my double bass and heard no crackle/pop or hiss at first; played it about 10 minutes and put it on standby. Then when I was practicing acoustically, about 5-10 minutes later (still on standby), I heard it again for about 4-5 seconds and it went away again.

I don't know if there is a break-in period on the tube since it was much worse at first; I haven't had time to play with it today yet.

Any one have any suggestions, comments?

Thanks,
John

PCR · #2 07-13-2010, 01:07 PM

I've been playing my Shuttle 9.0 for 2 months. No sizzle/crackle or tube break-in period.

I would give MF a call.

Good luck.

mambo4 · #3 07-13-2010, 01:28 PM

My GBE600 started crackling /farting a while back and the problem was buildup on the effects loop. the solution was to buy some contact cleaner from radio shack and spray the effects loop inputs, and plung/unplug a connector several times to clean it. Worked great after that. Now I routinely clean my inputs.

But don't take my word for it, I'm sure a GB engineer will post soon. Great customer service from those folks. (hi guys, keep up the good work)

Allen_VA · #4 07-13-2010, 01:30 PM

I've had that happen when the AC power cord was loose in the IEC power inlet on the back of the amplifier. Sounded like crackling/arcing/buzzing sounds. Might double-check the power cord is fully seated.

Flo'Daddy · #5 07-13-2010, 01:46 PM

Thanks PCR. Just got off the phone with Musician's Friend and they want it back and will send me another one when they receive it. I actually held the phone up to the amp when it was on and they heard it

. Nothing like auditory examples. Hearing is believing.

I appreciate the suggestion and prompt reply. This forum rocks!!!!!!!

Thanks again,

John

agedhorse · #6 07-13-2010, 08:31 PM

It's possible that it was a defective tube. That happens occassionally with tubes no matter gow mych burn-in we do. Could have also been launched by a shipping company warehouse material handling machine, hard to say without looking at it. MF will take care of you.

Flo'Daddy · #7 07-14-2010, 12:00 AM

Thanks agedhorse! They are taking care of it; part of the reason I went with Genz Benz was I played a friend's GB combo years ago and was impressed with the sound. Frankly, the customer service and advice on this forum greatly influenced my decision as well. I liked what I heard...

Thanks for replying; I knew I'd hear from you

John

Musicman20 · #8 07-14-2010, 02:46 AM

Great to know it's getting sorted, I knew it would

MichaelVee · #9 07-14-2010, 07:21 AM

John, I encountered a similar crackling/hiss problem with my new (at that time) Shuttle 9 last year. You may have seen my posts in the big Shuttle 9.0 discussion thread. As Andy noted, it could be related to the tube. I took my tube out and cleaned the pins and socket with Deox-it, and it got rid of the majority of the noise. Then when I took the amp out and played it on a different building wiring, it was dead silent at lower levels, so there is something amiss with my home wiring that caused at least some (if not all) of the original noise problem. That could also have been the case with your noise.

If you haven't already sent it back, try cleaning the tube pins with Deox-It. If you have a spare preamp tube around, also try swapping it out. Also try the amp with a different building in case it's your home wiring.

agedhorse · #10 07-14-2010, 07:40 AM

Intermittent power wiring can cause all kinds of unusual problems. Check to see that the IEC power cable is fully seated in it's socket, and try it on a different power source. I have seen noises caused by a loose binding screw on a receptacle or breaker just recently.

Flo'Daddy · #11 07-22-2010, 11:03 PM

Got my new Shuttle 9.0 today and am happy to report that there are no problems whatsoever! The amp is dead quiet; you can barely hear the fan with your ear up to the amp. It sounds great with my 62 Kay/Realist and my 2005 Calin Wultur/Revolution Solo II, as well as with all my electric basses.

I'm totally satisfied with my purchase; now I need a cabinet with 1 or 2 10" speakers to sit on top of my Aguilar 112 cab...thinking about the 2-10 Avatar Neo Cab, just missed one on ebay. Looking for something reasonable to utilize the power of this great amp. Thanks agedhorse and everyone here at TalkBass for your help and suggestions!!!

John

PurpleDrank · #12 08-25-2010, 05:34 PM

Hi guys,

I'm having a very similar problem with my Shuttle 6.0. I found this thread, so I figured I would resurrect it rather than starting a new one. New here so bear with me, haven't quite figured out the etiquette yet.

I have an intermittent crackle that usually happens right at start up and randomly afterwards. Happens wherever I play it, rehearsal space, my house, drummer's house, so I don't think power source is the issue. It's obviously preamp (and most likely tube related) because when I go through the effects loop and bypass the preamp it's dead silent. I tried replacing the Ruby 12AX7 with both a EHX and sovtek 12AX7 I had lying around (not the best, I realize, but they were both really low microphonics when I checked them in other amps).

Should I try a couple more tubes and expect a different result, or should I maybe try to use Deoxit on the tube socket and see if that helps?

I should note that this is the second tube (i'm guessing) problem I've had with this amp. Two days after I got it, the preamp gain output was really low. I shot an email to the Genz guys and Jeff told me to call him. I did and he sent me a new tube, no questions asked. Sure enough, it was a (barely) functioning really low output 12AX7 that was the culprit. Saved me a bunch of time and headache vs sending it back. Really great customer service and, after reading all the GB threads here, it's seems my experience is the rule not the exception.

Thanks for the help in advance. TB seems like a really great forum.

-PD

**jlepre** · #13 08-25-2010, 05:56 PM

Honestly,

Just contact GB support. The amp comes with a great warranty, and their customer service is GREAT!

JMHO

PurpleDrank · #14 08-25-2010, 05:58 PM

Yeah, no doubt.

Mostly just wanted to see if the deoxit on the tube sockect might save me some down time.

agedhorse · #15 08-25-2010, 07:45 PM

The 2 most common problems with all amps in general are defective tubes and effects loop jack switches, pretty much in that order. You have no idea how much time and effort we go through screening and burning in tubes in our test cycle. There's a REALLY limited number of suppliers out there and what they supply is what the entire marketplace gets.

papasound · #16 08-25-2010, 11:30 PM

I just want to say a big THANK YOU to Jeff Genzler for answering my email (within the hour of my sending it) regarding the "crackle - hiss" problem I had and promptly sending me a new tube which rectified the issue.

agedhorse · #17 08-26-2010, 09:55 AM

Quote:

Originally Posted by papasound

I just want to say a big THANK YOU to Jeff Genzler for answering my email (within the hour of my sending it) regarding the "crackle - hiss" problem I had and promptly sending me a new tube which rectified the issue.

Good news!

As consumers, we have gotten used to pretty darn reliable product (at least with many higger end brands) but collective memory becomes short when we forget how unreliable in general tubes are compared with today's solid state devices. Also, generally, manufacturers of tubes only warranty the tube for 90 days after sale, so the burdan falls on the manufacturer's of the equipment to keep the customer happy. In many cases the equipment manufacturer will eat the cost of tube replacement to keep the customer happy.

In a typical solid state or hybrid preamp like say the GBE-1200, there may be the equiv. of 2000 transistors and each one of them does a specific job. That would be like 1000 dual triodes, could you imagine the task of keeping a single device with 1000 tubes running (aside from the practical issues of size, weight and heat of course)? In general, a solid state preamp like this will be far more reliable than a tube preamp with only 3 tubes!

It's the sheer reliability of modern solid state devices that has improved the reliability of today's amplifier products. Do you think it would be possible to offer a 3 year transferrable warranty (including tubes) on an all tube product? Probably not, or not without increasing the cost of the product to reflect the cost of warranty tube replacement that would be encountered over the 3 year period.

Just some food for thought.

chicago_mike · #18 08-26-2010, 10:10 AM

One of the reasons engineers have used fets to emulate tubes. Transfex / transtube anybody? Is it better? Is it cheaper?....eh...

Im lucky as I have a box of tubes I can go thru just in case. Mullards, RCA, JAN rca's..etc..

rodneyat · #19 08-26-2010, 10:34 AM

Quote:

Originally Posted by papasound

I just want to say a big THANK YOU to Jeff Genzler for answering my email (within the hour of my sending it) regarding the "crackle - hiss" problem I had and promptly sending me a new tube which rectified the issue.

I had/have the same issue. I talked to Jeff on the phone the other day and a new tube is on the way. I am hoping it arrives today or tomorrow. Then, I can see if it fixes the problem. But, my symptoms were basically the same as yours and the amp was brand new, like yours. So, I am pretty sure it is a fairly common occurrence with tubes when they get shipped and bumped around.

**JxBass** · #20 09-05-2010, 01:37 PM

Same exact issue. Jeff has also shipped me a new 12AX7. After reading this thread I'm pretty confident it will fix the problem.