Shootout: KF650e vs DX1565

[Marlow Wilson]

Re: Shootout: KF650e vs DX1565

Hi Marlow:

Just FYI, I recently discovered with the UX8800 that changing amp sizes doesn't result in a limiter threshold adjustment, but in a passband gain change. Same end result, but the balance between one greybox and another in the same preset (tops vs. subs) will change.

EAW Forum: UX8800 Passband Gain vs. Max Amp Volts

Very interesting Langston. How then should I go about choosing amplifiers? In other words, without measuring (I have neither the faculties nor facilities), how do I know I'm not robbing the other passband of output potential on the one hand, but not needlessly spending money on amplifier power on the other?

 

[Langston Holland]

Re: Shootout: KF650e vs DX1565

No worries Marlow, EAW didn't do anything bad, just weird.

It's likely that external manipulation of the internal greybox data via the Amp Max Volts spec, such as limiter thresholds, was harder to arrange than just changing passband gain downstream of the greybox. Assume a situation where a greybox covers two passbands, low and mid/high. All will work as expected where one employs amps with similar output capabilities relative to the passbands.

Example: The KF730 is rated at 700 watts long-term into the lows and 350 watts long-term into the mid/highs. Assume the user chose amps with identical output capabilities respectively. In this case long-term max SPL would be achievable from both passbands. If the user chose two 700 watt amps, long-term max SPL would remain available and the additional long-term power in the mid/high amp would be ignored. If the user chose two 350 watt amps, max SPL of both passbands of the KF730 would be reduced 3dB in order to maintain balance across the loudspeaker's entire spectrum.

UX8800 outputs that are not part of that greybox are unaffected. Thus as both passbands of the KF730 are moved up and down, the subs and frontfills you might be controlling will stay put - possibly requiring manual rebalancing from the user.

The fact that no one has fussed about this until me shows you how little audible consequence it typically is.

 

[Peter Morris]

Re: Shootout: KF650e vs DX1565

No worries Marlow, EAW didn't do anything bad, just weird.

It's likely that external manipulation of the internal greybox data via the Amp Max Volts spec, such as limiter thresholds, was harder to arrange than just changing passband gain downstream of the greybox. Assume a situation where a greybox covers two passbands, low and mid/high. All will work as expected where one employs amps with similar output capabilities relative to the passbands.

Example: The KF730 is rated at 700 watts long-term into the lows and 350 watts long-term into the mid/highs. Assume the user chose amps with identical output capabilities respectively. In this case long-term max SPL would be achievable from both passbands. If the user chose two 700 watt amps, long-term max SPL would remain available and the additional long-term power in the mid/high amp would be ignored. If the user chose two 350 watt amps, max SPL of both passbands of the KF730 would be reduced 3dB in order to maintain balance across the loudspeaker's entire spectrum.

UX8800 outputs that are not part of that greybox are unaffected. Thus as both passbands of the KF730 are moved up and down, the subs and frontfills you might be controlling will stay put - possibly requiring manual rebalancing from the user.

The fact that no one has fussed about this until me shows you how little audible consequence it typically is.

Hi Langston,

The UX does not allow very many volts in or out-
http://www.eaw.com/products/ux8800.html- see preliminary spec sheet.

Input: Max level - 18 dBu, 6.2 V
Output: Max level - 18 dBu, 6.2 V @ >600 ohm load

So it becomes critical how you set the input and output gains. It would be very easy to overload the input and not get enough output to drive the pass bands.

I suspect what they have done is adjust the gains to achieve maximum noise and sonic performance while still being able achive the output voltage needed.

I used Powersoft K10s on my 730s - @26dB of gain they needed 6.34 volts to achieve full output - more than the UX can deliver, so I always ran the K10s on 32 or 35 dB.... with only 18dBu in and out there is not much to play with.



@Marlow,

There is no problem with the limiters, they work fine, and you will not need to do anything.
B U T you will need to time-align the subs to the tops. The latency for the tops is different to the subs, believe it or not.
Here are some examples of the addition sub delay needed when the boxes are physically aligned -

SB528 (5ms) with KF650i/E
SB528 (4.5ms) with KF730
SB730 (3.75ms) with KF730
SB730 (2ms -6db) with 2 x JFX260i BiAmp
SB750 (7ms) with KF750 (using KF750x2-4 TRI Greybox)
SB750 (8ms) with KF750 (using KF750+KF755 TRI Greybox)
SB750 (4.5ms) with KF730
SB850 (4.5ms) with KF730


Peter

 

[Ryan Lantzy]

Re: Shootout: KF650e vs DX1565

...

I completely agree that triamping this box and applying Gunness Focusing would likely increase MF/HF output by a bit, but by how much? I was already hitting the MF/HF with 1250 watts, and ignoring losses in the passive crossover, that's quite a bit of power. Is a real-world user going to hit that MF or HF with any more power than that?

Not totally related, but when moving from bi-amp to tri-amp on the KF650z I noticed a distinct, impressive, and very positive increase in clarity, maximum SPL, and rock-your-face-offishness. It's possible the bi-amp DSP settings I was using were trash, but it was the same processor doing the processing in both cases.

And 'throw' doesn't exist. With the exception of a proper line source, the inverse-square law applies: what is louder at the source will be louder far away. Period.

I think the perception of "throw" is sort of a mix of coverage and SPL. Something seems to "throw" further when it's narrow and loud.

 

[RYAN LOUDMUSIC JENKINS]

Re: Shootout: KF650e vs DX1565

I think the perception of "throw" is sort of a mix of coverage and SPL. Something seems to "throw" further when it's narrow and loud.

I think a lot of people see "throw" as you describe but here where I live it is more about how clear it sounds at distance. It is so much drier here most of the year compared to the rest of the country that the HF air absorption adds a whole other aspect to think about. My boxes get really loud but if I take them out in the heat of June when it is really dry they just don't seem to "throw" very far because all the clarity is gone within 150-200 feet or so regardless of how loud I turn them up. Adding back in HF Air Absoption EQ helps a little at distance but kills you up close where everyone wants to be listening anyways.