Gallien-Krueger owners -- advisory, power-down speaker thump
Todd H.
FYI--if you've purchased a GK since February 2001, there may be a
recall of sorts available to you. GK isn't being proactive about it
(which is unfortunate), they don't seem to be advertising this to
either its users or dealers, so I'll be happy to tell you.
GK 1001RB's manufactureed between February and May of 2001 contained a
subtle design issue that may cause excessive speaker thumping when
powering off the unit. I learned this when GK Engineering responded
to my concern to them about the issue and questioned whether it was a
design or manufacturing issue. They confirmed a design tweak from Feb
2001 that had an unintended side effect. They corrected the issue in
May, and tightened up final testing to screen for the problem.
It's possible that related GK amps like the 700RB are also affected
since I believe they share a common preamp design.
If your unit thumps on power off, check your serial number. The 4
digits before the E indicate the manufacture date. The format is YYWW
where YY is the year (01) and WW is the work week. If the work week
is in the rough range of 05 to 22 and you notice an unusually loud
speaker thump, there is a modification that can be performed by an
authorized GK repair facility that would be covered under an unexpired
warranty. The issue can be avoided by zeroing the master volume
before turning the unit on or off. The tradeoff will be the wait time
for repair versus this inconvenience of turning down the master.
I recently purchased and returned a 1001RB manufactured in 0108E (Late
Feb 2001) that had the problem. I obtained a unit manufactured in
September 2001 and there is no issue with power down speaker
transients.
Best Regards,
--
Todd H.
http://www.toddh.net/
Fran Diaz
I'm glad to see you got a new (and OK) unit. Enjoy it
keep groooovin'
Fran Diaz
Todd H.
Revised -- see below
bmi...@toddh.net (Todd H.) writes:
> FYI--if you've purchased a GK since February 2001, there may be a
> recall of sorts available to you. GK isn't being proactive about it
> (which is unfortunate), they don't seem to be advertising this to
> either its users or dealers, so I'll be happy to tell you.
>
> GK 1001RB's manufactureed between February and May of 2001 contained a
> subtle design issue that may cause excessive speaker thumping when
> powering off the unit. I learned this when GK Engineering responded
> to my concern to them about the issue and questioned whether it was a
> design or manufacturing issue. They confirmed a design tweak from Feb
> 2001 that had an unintended side effect. They corrected the issue in
> May, and tightened up final testing to screen for the problem.
>
> It's possible that related GK amps like the 700RB are also affected
> since I believe they share a common preamp design.
>
> If your unit thumps on power off, check your serial number.
Bob Gallien wrote me with a more accurate test to verify that a
recently-manufactured unit was manufactured with the mod:
Dear Todd,
The final test is the serial number. We put a code in our serial
number which gets updated every time we make any change in our
products, even a screw or washer. Any unit with E03 or greater
has this correction.
Best Regards,
Bob
I'm not sure what "or greater" is mean to embody, however
My "bad" unit serial began with 1Y0109E09xxxxxx.
My "good" unit serial began with 1Y0136E03xxxxxx.
> The 4 digits before the E indicate the manufacture date. The format
> is YYWW where YY is the year (01) and WW is the work week. If the
> work week is in the rough range of 05 to 22 and you notice an
> unusually loud speaker thump, there is a modification that can be
> performed by an authorized GK repair facility that would be covered
> under an unexpired warranty. The issue can be avoided by zeroing
> the master volume before turning the unit on or off. The tradeoff
> will be the wait time for repair versus this inconvenience of
> turning down the master.
>
> I recently purchased and returned a 1001RB manufactured in 0108E (Late
> Feb 2001) that had the problem. I obtained a unit manufactured in
> September 2001 and there is no issue with power down speaker
> transients.
Ben H
weeks....
"Todd H." <bmi...@toddh.net> wrote in message
news:lypu5mh...@k2.onsight.com...
JF Harvey
Thanks for letting us all know about this problem. I recently bought a 1001
RB and it does go "POP" when I turn it off. I just turn the volume off
before I turn it off and go on my merry way. It doesn't seem worth it to me
to bring it in strickly for this problem. I wonder, though, does this hide
a bigger problem about the amp? Did the technician who fixed it say you
would have had bigger problems if you hadn't brought it in? Thanks for
letting me know. By the way, are you happy about the 1001 RB besides this
problem?
Take care,
John
"Todd H." <bmi...@toddh.net> wrote in message
news:lyelm32e...@k2.onsight.com...
Scott b
with:
"All of our amps have a slight thump when turned off" Slight???
What a crappy reply! This after telling of my 400RBIII which has a STRONG pulse
on power down. How insulting. Great customer service!
ScottB
Joe
Years ago the 120ML lunch boxes were eventually blowing up at "Turn On".
The said nothing, amps were coming in a rate of 2-3 per week
As authorized service I complained and demanded a solution
It was costing us a fortune to honor the warrantees and wait 90 days for
reimbursement from GK.
We were buying A56 A06, TIP 30, 31, 33, 34 bag fulls to keep up
There answer......they dropped and stiffed us.
In 1987 before Sam Kinison and John Entwistles show in Anaheim
I demanded to see the service manager at the NAMM show, they said he was no
longer with us we are very busy"
and Bob Galleon hands me this card.
The following week they started the same BS all over again.
The GK 250ML's were revised for startup/shut down stability several times
starting at around Ser #36000
The story about the self torching 400B Darlington output amps is even worse.
.........'F" em
Joe
Scott b wrote in message <3C16CAF2...@pacificnet.net>...
Todd H.
> Hi Todd, Thanks for letting us all know about this problem. I
> recently bought a 1001 RB and it does go "POP" when I turn it off.
> I just turn the volume off before I turn it off and go on my merry
> way. It doesn't seem worth it to me to bring it in strickly for
> this problem.
Yeah, that's a good question. If it doesn't bother you, turning the
master volume does the same thing and is probably even more
foolproof. I had to get mine corrected out of principle, but I'm
more anal retentive on design issues than most.
> I wonder, though, does this hide a bigger problem about the amp?
GK didn't indicate any other problem with the amp so you're probably
fine. FWIW, the 700RB is similarly affected since it has an identical
preamp design. The date range is the same--"We know for sure that the
amps between mid-February and the third week of May have this thump."
GK's seen fewer complaints about the 700RB, but they figure it's just
because of the lower power rating and a consequentally less
significant thump.
The 400RB and 800RB aren't affected by this problem because they've
never had any power on/off protection circuitry (again according to
the emails I've gotten from GK). They thump in both directions, but
they can't source current like the 700RB and 1001RB either, so it's
less of a big deal with those lower wattage amps.
> Did the technician who fixed it say you would have had bigger
> problems if you hadn't brought it in?
I had just purchased the amp that week and noticed the problem in my
first night of using it. I returned the amp directly to Guitar Center
under their 30-day return policy and requested another one from the
back, got lucky to get a "good" one, emailed GK about defectivity, and
their reply confirmed my suspicion of a design defect.
The "tech" with whom I exchanged several emails was actually GK's head
of engineering who was probably engaged when I emailed Bob Gallien
with a copy of the posting I made in this forum. At one point I
received an email from Bob Gallien himself.
What's funny is that, today I got an email reply from David Eden on a
biamping question, so I'm having a banner freakin week! :-)
> Thanks for letting me know. By the way, are you happy about the
> 1001 RB besides this problem?
Oh yeah. I'm keeping it. If only to tell the story of my responses
from GK's director of engineering and Bob Gallien. :-) Seriously
though, oodles of power, quiet signal path, quiet fan that I've never
seen even have to kick on yet actually, very light, and I think I wore
the wifey down enough to get over the price tag and call it Christmas.
As picky as I am, I'd probably have kept it even with the thumping
issue, though it'd have irritated me as an EE. Nothing else out there
sources 540 Watts into 4 ohms, weighs 18 pounds and has that nice GK
tone in a 2-rack-space package.
Todd H.
> Just finished a communication with G-K about this and they just
> brushed me off with: "All of our amps have a slight thump when
> turned off" Slight??? What a crappy reply! This after telling of my
> 400RBIII which has a STRONG pulse on power down. How
> insulting. Great customer service!
I asked whether the 400RBiii and 800RB were affected by the design
flaw I uncovered in my 1001RB. Their answer:
GK> Todd,
GK>
GK> This problem does not occur on the 800RB or the 400RBIII. It did
GK> occur on some 700RBs since they use the same preamp as the
GK> 1001RB, although we haven't had as many complaints on the 700RB
GK> as with the 1001RB. The 400RB and 800RBs always had a slight
GK> turn-on and turn-off pop since these didn't have any muting
GK> circuitry as our newer amps do, but they were nowhere near the
GK> same loudness as the "defective" 1001RBs.
GK>
GK> Regards,
GK>
GK> [del]
GK> GK Engineering
The 700RB and 1001RB's misbehavior on power-down was what was
defective in the design of 700RB and 1001RB amps manufactured between
mid-February and the third week of May 2001.
Now, what confuses me a little, though, is that the 400RB-iii manual
claims power up/down protection circuitry just like the 1001RB does.
What are the 4 digits ahead of the E in your serial number?
Scott b
master when not in use.
The documentation indeed states the same protection circuitry as the
1001/700 series.
My 1001 is fine and I can run it full-up on or off with just a tiny bump.
I REALLY love these heads and am saddened to get a glimpse of the kind of
support they offer.
Seems to be a trend at all these companies now days.
Love that G-K sound,
ScottB
jason
Why don't you just send your amp to GK for repairs ? What's all this
jibber jabber regarding turn off pop. I've played for years, seems
like all my amps have a bit of a turn off pop.
Jay
Scott b <jg...@pacificnet.net> wrote in message news:<3C170409...@pacificnet.net>...
Heywood Jablomi
> What's funny is that, today I got an email reply from David Eden on a
> biamping question, so I'm having a banner freakin week! :-)
I call bullshit. There IS NO David Eden. The Pres. of the company is David
Nordshow, the company's name is Eden, and "David" is merely a product line
name, as a tongue-in-cheek comment in response to SWR's "Goliath" series.
Todd H.
Feel free.
Want a copy of the email? Just says "Dave" and came in response to my
query being unanswerable by their speaker support person who suggested
me emailing David. The reply included specific technical
recommendations for bypassing the crossover for using a biamping
arrangement with a single Eden cabinet. Whatever the last name, it's
evidently the designer of the speaker cabinet.
I'm way too old to get jollies from making things up, (or for that
matter, from using interesting names in attempt to solicit fellatio
from a predominately male newsgroup). I'm sure I wouldn't be the
first person in the newsgroup to have corresponded with David.
Wes Rhoades
of the company.
http://www.eden-electronics.com/compinfo.html
Wes
Heywood Jablomi
I don't doubt you got an e-mail from a "Dave" at Eden Electronics (possibly
even the creator Mr. Nordshow himself), but it certainly wasn't "David
Eden".
"Todd H." <bmi...@toddh.net> wrote in message
news:lyzo4o1...@k2.onsight.com...
Todd H.
As a result of our email conversations, GK has agreed to issue a
service advisory to dealers on this issue with the 700RB and 1001RB's
and ask them to screen their current inventory. Also note the
discovery of at least one unit manufactured after May of 2001 that has
the issue:
Latest updates, reference, including email from GK on the service
bulletin:
http://www.toddh.net/music/gk/
I also learned that the 400RB-iii's do include a speaker protection
circuit, but its design is different than the 700 and 1001RB's. A
normal 400RB-iii will give a slight thump and a click on power down.
The abnormal 700RB's and 1001RB's give a massive thump and snap on
power down. A normal 700RB and 1001RB gives no sound on power down.