LH1000 and GK Ultralight Cabs

[TheRigere]

Just picked up the Hartke LH1000 head and its awesome but I'm pissed that my GK Ultralight Series 4x10 and 1x15 are farting out with it. At first I thought it was that I was pushing too much EQ so I lowered it. It certainly helped the issue and now I get the farting only on my B-string occassionly if I play a little to boiseterously on it... I still think its an eq issue but oddly i can play my open E fine then same note fingered on Bstring and it can fart.

Now granted i previuoslu ran a GK 700rbii thru the same cabs fine and the Line6LD400 with no issues. Now it says the GKs are 400 watts speakers @ 8ohms so technically it should be fine...but its not...

Any thoughts or similar experiences? I love the head and the cabs and I really don't feel like buying another cabinet.. but a farting cabinet at a gig is way more embarassing than a farting bassist.

[Tractorr]

You can definitely get a cab rated at 400 watts to fart out with the 225 that each side of the LH1000 is providing. Also be careful if you are making the 4X10 fart out then that 1X15 is about to bite it.

[TheRigere]

Originally Posted by Tractorr

You can definitely get a cab rated at 400 watts to fart out with the 225 that each side of the LH1000 is providing. Also be careful if you are making the 4X10 fart out then that 1X15 is about to bite it.

Yeah... I've turned the bass eq down and it helps but Im on the verge of not like the sound ya know... guess I'll have to bite the bullet and buy yet ANOTHER cab... the Hydrive 410...would love the 810 and can get one for the price of the 4x10 but I'd also have to buy a new car to get the darned thing anywhere... ugh...

So do you think it a eq adding to much gain issue or like my guitarist says, " GK is like the Behringer of bass equipment" lol

[joelb79]

The ultralight cabs are rated at thermal failure power limits. The speaker cone will handle far less power at low frequencies because the cones are not able to keep moving linearly past a certain mm of excursion. You can actually over-exert your cones at a much lower power than the thermal rating max power at low frequencies with less power than they are rated for. Even though my epifani UL410 said it would handle 1500w, I knew that cone over-excursion would take place somewhere in the range of 300w-500w. The difference between 300w and 500w is under 1db, so that is not necessarily noticeably different.

The only further troubleshooting step I would add is turning your input gain down some and raising the master volume; just to be on the safe side that you are not over-driving the preamp input stage. Take the input gain down and try raising the master to add back the same volume and see if the speakers still act the same way. If the speakers don't break up the same and that cleaned up the sound, then likely you were hearing preamp clipping instead.

[mudpup]

Originally Posted by joelb79

The ultralight cabs are rated at thermal failure power limits. The speaker cone will handle far less power at low frequencies because the cones are not able to keep moving linearly past a certain mm of excursion. You can actually over-exert your cones at a much lower power than the thermal rating max power at low frequencies with less power than they are rated for. Even though my epifani UL410 said it would handle 1500w, I knew that cone over-excursion would take place somewhere in the range of 300w-500w. The difference between 300w and 500w is under 1db, so that is not necessarily noticeably different.

The only further troubleshooting step I would add is turning your input gain down some and raising the master volume; just to be on the safe side that you are not over-driving the preamp input stage. Take the input gain down and try raising the master to add back the same volume and see if the speakers still act the same way. If the speakers don't break up the same and that cleaned up the sound, then likely you were hearing preamp clipping instead.

Hartke LH1000 doesnt have an input gain control - just a volume knob.

[Tractorr]

Originally Posted by mudpup

Hartke LH1000 doesnt have an input gain control - just a volume knob.

Yeah that is one of the annoying parts about the LH1000 design that it doesn't have a separate master control especially with a tube pre. Though Hartke doesn't seem to go the full deal tube anyways at least the tube in my Hartke 2000 doesn't do much other than add a very slight mid range emphasis while softening the attack very mildly.

GK makes quality cabs so the problem lies in the bass and volume control.

What I would do is leave the EQ flat and then turn the volume up until the i heard the first bit of farting out. Then I would back the volume down until there was no farting out whatsoever. Once that level was set I would make minor EQ adjustments to taste (likely raising the mid control to cut through the mix but that is me). If the resulting eq adjustments caused more farting then turn the volume down some more to counteract.

There is no reason why that head and those cabs should not produce a usable result unless of course something is broken.

[joelb79]

Originally Posted by Tractorr

Yeah that is one of the annoying parts about the LH1000 design that it doesn't have a separate master control especially with a tube pre.

What I would do is leave the EQ flat

I stand corrected. But I do know that flat is not noon on this amp. Lows at 2, Highs at 2, mids at 10 (Full) is flat.

[jjk2007]

Originally Posted by joelb79

I stand corrected. But I do know that flat is not noon on this amp. Lows at 2, Highs at 2, mids at 10 (Full) is flat.

I was going to say this too. Run the 2-10-2 EQ setting and see what happens.

[Tractorr]

Originally Posted by joelb79

Lows at 2, Highs at 2, mids at 10 (Full) is flat.

Good to know.

[B-string]

So the cabs are fine with the G-K and Line 6 but not the Hartke and you believe it is the cab's fault?