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**pastorola** · 07-01-2014, 04:38 PM

Re: Driver replacement for Swope sub???

If I cannot solve this question I will probably aim for the Digger8 sub. Comments on that? The JBL GTO804 is also available in Sweden and a lot cheaper than the HiVi SP10 and the Dayton 10".

**jsr** · 07-01-2014, 04:56 PM

Re: Driver replacement for Swope sub???

Based on the T/S parameters, I would not think the RSS265HO to be a drop-in replacement for the SP10. I think Paul measured the Swope sub to be flat to 20Hz in-room response, so whether it performs the same for you will depend on your room and setup. The SP10 in that size cab will roll off sooner (in the 30s) on it's own, so your room gain will determine how low it goes.

The Digger8 is designed to be flat without room-gain. That means there will be a bump in output at the lower frequencies (30s and below)...how much depends on your room. This is great for HT. But the Digger8 was designed as a compact_low_cost_low_extension sub with zero boost needed. It's not designed to do 20Hz at 110dB as a single unit. But the low cost allows for multiple units that will raise SPL while also helping to minimize room modes. But you do need more than 1 if you want high SPL, whereas the Swope (and other designs with larger drivers) will handle more power and thus offer a bit more SPL as a single unit. Just depends on what compromises you're willing to make.

The Continuum sub may be another option for you.

**pastorola** · 07-01-2014, 05:19 PM

Re: Driver replacement for Swope sub???

The room is appr. 43 m2 (470 sq.ft?) and 2.4 meters high so there is some space to fill.

**kevin007** · 07-01-2014, 05:24 PM

Re: Driver replacement for Swope sub???

Originally posted by pastorola View Post

The room is appr. 43 m2 (470 sq.ft?) and 2.4 meters high so there is some space to fill.

I fill a larger space then that with my 2 digger 8's. They go so low it is ridiculous. My son played his woofer cooker tracks from you tube and they danced all over the floor! The drivers were actually moving with freg sweeps down to 8Hz! The diggers are a pretty killer sub!

Kevin

**jsr** · 07-01-2014, 05:30 PM

Re: Driver replacement for Swope sub???

Thanks Kevin!

The room my single Digger8 is in is about that size (slightly larger...~500 sq.ft.) and it works fine for HT duty for me (loud enough that my wife is yelling at me already during moves like Pacific Rim).

**fbov** · 07-01-2014, 05:46 PM

Re: Driver replacement for Swope sub???

I did a little modeling with Unibox...

Paul didn't specify an internal volume, so I calculated 35L based on his drawings (inset amp panel, partial double baffle, subtracting port) but he did spec the port at 3x25" or 7.6x63cm. I'm getting a 21Hz F3 with a slight (0.5dB) peak at 61Hz.

The RSS265HO-4 has very similar response down to 40Hz, but with a 23Hz F3 and a 0.5dB peak at 24Hz rather than 61Hz. This peak can be tamed by reducing box internal volume, but that results in a longer port, and there's no room. I expect the lower peak will more than make up for the higher F3 as none of the differences is what I consider large, and should be inaudible to most folks in all but the most specific test scenarios.

The only significant difference is excursion below 20Hz. The RSS265's excursion just keeps rising, making a good infrasonic filter, such as that found in the BASH 300 amp Paul used, an absolute necessity rather than good practice, in the event of full-power use. I'd have to say that response within 0.5dB with similar power and filtering needs is a pretty good drop-in replacement!

HAve fun,
Frank

**jsr** · 07-01-2014, 06:25 PM

Re: Driver replacement for Swope sub???

I recall he mentioned volume is 30L.

**Paul Carmody** · 07-01-2014, 06:58 PM

Re: Driver replacement for Swope sub???

Since the SP10 it's, for all practical purposes, NLA, I wholeheartedly support this endeavor to find a replacement woofer. I haven't checked Frank's math, but I'd definitely say he's of to a good start.

**pastorola** · 07-01-2014, 07:01 PM

Re: Driver replacement for Swope sub???

Originally posted by fbov View Post

I did a little modeling with Unibox...

Paul didn't specify an internal volume, so I calculated 35L based on his drawings (inset amp panel, partial double baffle, subtracting port) but he did spec the port at 3x25" or 7.6x63cm. I'm getting a 21Hz F3 with a slight (0.5dB) peak at 61Hz.

The RSS265HO-4 has very similar response down to 40Hz, but with a 23Hz F3 and a 0.5dB peak at 24Hz rather than 61Hz. This peak can be tamed by reducing box internal volume, but that results in a longer port, and there's no room. I expect the lower peak will more than make up for the higher F3 as none of the differences is what I consider large, and should be inaudible to most folks in all but the most specific test scenarios.

The only significant difference is excursion below 20Hz. The RSS265's excursion just keeps rising, making a good infrasonic filter, such as that found in the BASH 300 amp Paul used, an absolute necessity rather than good practice, in the event of full-power use. I'd have to say that response within 0.5dB with similar power and filtering needs is a pretty good drop-in replacement!

HAve fun,
Frank

Thanks for that! Looks like a Swope-like sub with the Dayton driver is an option after all :-)

Really considering the Digger8 still. Having such a small sub sporting only an 8" driver performing 20 Hz really is tempting... Just found out a place here that offers the Dayton PR at a reasonable price. In that case I only have to order the BASH amp together with the OSMTM parts from PE when it's time to build.

**pastorola** · 07-01-2014, 07:17 PM

Re: Driver replacement for Swope sub???

Originally posted by Paul Carmody View Post

Since the SP10 it's, for all practical purposes, NLA, I wholeheartedly support this endeavor to find a replacement woofer. I haven't checked Frank's math, but I'd definitely say he's of to a good start.

The designer himself. Bowing in Swedish humility...

Have you ever heard the Digger8? Can you compare it to the Swope? I will use the sub with Overnight Sensation MTM's, for HT use but priority one is music. It has to perform well with progressive rock like Dream Theater, Transatlantic, or this, Neal Morse:

Neal Morse Momentum LIVE

**jsr** · 07-02-2014, 10:22 AM

Re: Driver replacement for Swope sub???

Here's some sims based on the T/S parameters PE lists for a few subs. All are in 30L internal enclosures. All use 3in vent, but the other ones worked better with a slightly longer vent length. All showed >30m/s (around 35m/s) port velocities, so ports flared on both ends recommended to reduce/avoid chuffing.
All seem like pretty decent candidates as SP10 replacements (strange that all their T/S parameters varied quite a bit from one another). Pick which you like best and stuff it in the box! Remember to take into account the port volume...that's a LONG port!...takes up about 3.4L of space.

SP10
Response shape = Rounded
F3 = 24 Hz
F6 = 21.5 Hz
F10 = 19.6 Hz
Port = 3 x 25

RSS265HO
Response shape = Flat
F3 = 21.9 Hz
F6 = 20.3 Hz
F10 = 18.6 Hz
Port = 3 x 29
Comments = Not as much power handling as SP10. Flatter response and lower extension. Slightly lower sensitivity.

UM10 Ultimax
Response shape = Rounded
F3 = 26.8 Hz
F6 = 22.5 Hz
F10 = 19.4 Hz
Port = 3 x 29
Comments = Similar rounded response curve to SP10. About equal power handling.

TC Epic 10
Response shape = Rounded
F3 = 25.4 Hz
F6 = 22.1 Hz
F10 = 19.6 Hz
Port = 3 x 29
Comments = Similar rounded response curve to SP10. Slightly less power handling. About equal sensitivity.

Peerless 830452 XLS
Response shape = Flat
F3 = 24.25 Hz
F6 = 21.7 Hz
F10 = 19.4 Hz
Comments = F3, F6, F10 most closely matches SP10. Flatter response than SP10. Least power handling of the group. About equal sensitivity to SP10.

**pastorola** · 07-02-2014, 05:30 PM

Re: Driver replacement for Swope sub???

Hey that was really nice, thank you for that!

Another question, very related. Today I got my hands on a Behringer Super-X PRO CX2310 stereo 2-way crossover with separate sub output w/ optional 25 Hz HP filter.

Could this be used to properly filter a regular power amp to power this sub instead of using a sub plate amp?

**pastorola** · 07-02-2014, 05:36 PM

Re: Driver replacement for Swope sub???

Yet another:

Shippping and customs fees make the BASH amps cost quite a lot to get here. Looking at plate amp options here at home base (Sweden). Building this sub to play together with Overnight Sensation MTM, how many watts would you say I need in the sub amp to match those?

**Audiotorium** · 07-02-2014, 06:16 PM

Re: Driver replacement for Swope sub???

Originally posted by pastorola View Post

Yet another:

Shippping and customs fees make the BASH amps cost quite a lot to get here. Looking at plate amp options here at home base (Sweden). Building this sub to play together with Overnight Sensation MTM, how many watts would you say I need in the sub amp to match those?

Its not 'how many watts do you need to match the OS MTM', but more like 'how many watts do you need to use the full potential of the sub you are going to build'.