Ampeg 410hlf replacement speaker wiring

[young774080]

I'm replacing all four of the speakers in my ampeg 410hlf due to the fact that they are all blown. I'm buying four 8 ohm 200 watt handling speakers and running a 1001rb-II which will either run at 750w @ 4 ohm or 480w @ 8 ohm. Anyways the original reason why the speakers blew is that the 410 only is 500 watt rms and I crank that head. So based on this information here's my question. If I wire the hlf @ 8 ohms the head will only push 480 w but the cab would be able to handle 1000 watts, using series parallel wiring, or if I wire the cab at 4 ohms the head now pushes 750 w but the cab would only be able to handle 800 watts. What's the best way to wire this because I don't want to blow these speakers too?

[MuzikMan]

Changing the wiring should not affect the thermal handling of the cab as far as I know. FWIW the thermal handling will not tell you the limits of mechanical excursion, which is probably why you blew all four drivers.

[young774080]

Well how do I tell what the mechanical excursion is for a particular speaker based off of its specs, also how do I keep the mechanical excursion of a speaker to a minimum.

[Bass_Pounder]

If you have four 8 ohm speakers, there is NO possible way to make it a 4 ohm cab.

No matter how you wire it, it will have a THERMAL rating of 800 watts.

If you did not buy the right speakers for the cab, you will most likely blow them again (that is if they even sound decent enough to play with).

[RickenBoogie]

Yes, changing the speakers in the cab is an unknown, unless you modelled the cab and bought spkrs that match the box. The wattage rating on the spkrs is the point where the voice coils melt, iow, meaningless. You are headed directly for fail- stop, download WinISD, and learn how to find the proper replacements, (or recone what you have). Then, learn how to avoid blowing spkrs through proper use of eq and volume.

[billfitzmaurice]

Originally Posted by young774080

Well how do I tell what the mechanical excursion is for a particular speaker based off of its specs

xmax. But Ampeg drivers have high xmax anyway, so you probably did simply overpower them.

also how do I keep the mechanical excursion of a speaker to a minimum.

Don't play so loud. Or use more speakers.

[BassmanPaul]

Please read the FAQs on page one for more information. For your cab to perform properly you need to replace the drivers with ones identical to the originals.

[Rockmusician]

Not sure why Ampeg has lowered the power handling on the 410HLF. I bought one 11 years ago that was rated at 1,000 watts. The following year, a friend of mine bought one that was rated at 800 watts. Now they are 500 watts. It makes me wonder what else Apmeg is doing to cut costs. I understand what you are trying to do, but I don't think it can be done. It might be less expensive to buy a 4 ohm cab.

[billfitzmaurice]

Originally Posted by Rockmusician

Not sure why Ampeg has lowered the power handling on the 410HLF. I bought one 11 years ago that was rated at 1,000 watts. The following year, a friend of mine bought one that was rated at 750 watts. Now they are 500 watts.

If it was rated at 1000 watts it was completely specsmanship, as the drivers would not take more than 125 watts each before reaching excursion anyway. The 500 watt rating is an honest one. AFAIK their drivers have not been down graded.

[omie]

How has this worked out for you? And how do you run the 1001rb at 8ohms without 2 cabinets?

I currently have a 410hlf 500w 4ohm and a 400rbiv and would like to upgrade to a 700rb or 1001rb but i'd need a 2 new cabinets (at 8ohms) if i wanted more speakers. I'm torn.

[Jerrold Tiers]

Originally Posted by billfitzmaurice

xmax. But Ampeg drivers have high xmax anyway, so you probably did simply overpower them. Don't play so loud. Or use more speakers.

750W should NOT overpower the cab....... with a 750W amp, about the most you can ever manage to get into the cab musically is 350W....... we tested, and that's what we came up with. The resulting sound was virtually 'thrash metal", and it was hard work to get there.

I think it may have BEEN an X-max issue.......

I'm gonna speculate that the lows were boosted quite a bit...... the HLF is ported, and ANY ported cab loses control of the speakers below box resonance*...... Way down there you can blow high power drivers with 50W of amp..... because the only thing restraining the cone is the suspension. It's like driving the speaker with no enclosure.

When you boost lows, the boost can go well below the speaker box resonance, and then down-tuning, or just plain non-resonant string vibrations from your fingers on teh fretboard, etc, etc, can push the speakers into radical movement.

* there are ways to add air friction for cone loading below box resonance, but they are virtually never used anymore, apparently.

[MuzikMan]

Originally Posted by Jerrold Tiers

* there are ways to add air friction for cone loading below box resonance, but they are virtually never used anymore, apparently.

Would you be able to elaborate on this point?

[allexcosta]

Originally Posted by billfitzmaurice

Ampeg drivers have high xmax anyway(...)

How high?

[billfitzmaurice]

Originally Posted by allexcosta

How high?

4.7mm. The average for tens is 4mm. Irrespective of the power rating a ten that doesn't have more than 4.7mm xmax won't go any louder than the Ampeg driver.

[Jerrold Tiers]

xmax affects primarily LOW end performance...... if you can get into an xmax problem with a 10" at a midrange frequency, you have a lot of power....

if you define the acoustically useful power handling at a low freq, then yes it is xmax limited. If, as has been often the case, you define it at a higher freq, in the midrange, etc, then it can be essentially the same as the electrical power capability. Some define it at the minimum impedance point, which is usually from 300 to 600 Hz.

As for cone control, perforated metal over the back of the speaker frame is one way.... flow through the holes adds friction.

When the box presents a high impedance to the cone, around box resonance, the frictional effect is small. Above that, the cone movement is decreasing, so the effect is less (can be significant).

below resonance, the frictional loading controls the cone movement, at least more so than leaving it completely free to "flap".