Originally Posted by randyc1
I don't get this paragraph of yours""
With the HO-44, coils wired in series, drivers in parallel, you could show the amp a net 4 ohm load. No way to get 4 ohms net from a pair of HO-4s. Unless you're using one SA1000 per HO-4, but your text doesn't read that way to me. "" ?
Each dayton RSS driver is wired in Series ,... Then both subs are in parallel at the SA1000 for a total of 4ohm load .
I then tested just 1 RSS ( in case of cancellation) at a 8 ohm load and got very similar results.
Yes im using LFE
6 yr old Yam rx-v 657
The point I was trying to make is clarifying which sub drivers you're using. You've said multiple times in this thread and others that you're using the RSS315HO-4. However, the RSS315HO-4 is a single coil 4 ohm sub. If you wire a pair in parallel, you get 2 ohms at the amp; in series you get 8 ohms. A single shows the amp 4 ohms. To achieve the wiring configurations you've described, you must be using the RSS315HO-44
, a dual voice coil/4 ohm per coil driver.
To get accurate answers, you must first provide accurate information.
In reality, any 12" subwoofer should easily reach 200Hz without a problem. Thanks to good venting and low distortion motors, the RSS315 drivers would appear to be useful up towards 1kHz if beaming weren't becoming an issue due to the ratio of wavelength to driver diameter. One of the 315HF models, either the 8 or the 4 (can't remember), has been incorporated as the woofer in a 3-way design. You don't see many 12" subwoofer drivers being used in that application.
Unfortunately, as measured, it appears the room is the dominant factor in your current measurements. It looks like both the KEF and HO-44 are showing many of the same peaks/dips, which tells me the room is dominating your measurement. As someone else mentioned, you also probably haven't accurately level matched the two sub amps so the KEF "appears" to have more high frequency by virtue of being louder. The HO-44 might suffer a little more of an inductance hump than the KEF, giving the appearance of a more rolled off high frequency response, but we can't tell from your current measurements. If you want to compare sub to sub, do a close mic'd measurement with the mic 1/2" or so from the dust cap of each driver. This will take the room out of the equation and show you what each driver is actually doing...above tuning in the case of the HO-44. Don't be surprised if the response is still similar since 200Hz should't really be a challenge. If you want to see what the drivers' upper frequency limits are, you're going to need to run them off of full range amps instead of your current amps that have built-in lowpass filters.
And, while I'm writing a book :-). You may want to double check your receiver's settings since you seem to be confusing YPAO with the DSP enhancements. The RX-V657 does have YPAO. YPAO is Yahama's attempt at room correction and is separate from their various DSP enhancement modes. In addition to automatically setting distance and level for all channels, YPAO attempts to equalize the main channels (sub excluded) frequency response using parametric EQ on each channel. If you ever ran the auto-setup routine and didn't go back and manually disable EQ in the setup menu, then you're applying this automatic EQ to your current setup. Even though your version of YPAO doesn't EQ the sub channel directly, depending on how YPAO actually works, the capability of the sub used during the YPAO measurement could influence the EQ applied to the mains.