RSS315HF-4 as the anchor of a 3-way???

[Jeff B.]

Re: RSS315HF-4 as the anchor of a 3-way???

Well I got some listening done with one of the cabinets, just to get an impression of the capabilities. I pulled out the old Sansui G8000, a very generous 130W capability with power meters to give me an idea where the output is to keep it clean. Nothing fancy for the source, just headphone output from the laptop into the Sansui, running WAV format for the music in Media Player. Far from optimal.

I adjusted the output so that the meter was hovering around 10W.

The cabinet will need some cross bracing for the side panels. The baffle doesn't need anything to stiffen it up. Solid as a rock. Even as large as the side panels are, the nature of the build has created really stiff walls that don't move very much. But from a simple touch test, I could tell that a brace or two would improve things.

That said, after I spent an hour listening to some cuts, I got around to playing Allison Krauss, "Deeper than Crying" and was just mesmerized. I think the mid and tweet are so close to right that I don't know that any more tweaking will improve anything. And without the stereo pair in their final places in the listening room, it's tough to tell if the overall bass levels are right. But during Hotel California - Live/Acoustic, the big drum and bass seemed to be all there, with a real visceral quality to the lows. I can't wait to get the second one up for final voicing.

....and I can't wait to hear the pair at some future gathering. The raw cabinets sure were impressive when I saw them in April.

Jeff

[Pete Schumacher]

Re: RSS315HF-4 as the anchor of a 3-way???

There's becoming no doubt in my mind about the musical quality of the RSS subs. They really are woofers, and can be considered such, remaining articulate to well beyond sub range. Dan's HOSS and BassLines have that awesome low end, but he's done both actively, with separate amps. It's really neat to find out how the subs do in a passive XO, and they really do shine.

Right now, they're crossed at 200Hz using 8mH iron core and 100uF film capacitor. I sure do like what I hear so far. I took care of some leaks around the PR this morning and bass sure tightened up afterward.

I decided that the XO will be outboard. There's some left over veneer which an be used to cover the XO enclosures. So the drivers all have their own 5-way binding posts on the rear bottom, just below the PR. That sure will make playing with various XO implementations an easy proposition.

One thing I want to try is using an impedance compensation circuit for the tweeter. Modeling suggests that better phase tracking is possible using it. It does add 3 more components however. But since it's easy enough to try, why not?

And for the next few hours, I'm just going to run a 40W sine wave at 12Hz through them. Both the PR and RSS are moving near Xmax, and there's nary a sound from them. I do hear just a touch of the 2nd harmonic at 24Hz but at 2" p-p excursion on both the PR and woofer, I'm not surprised. It is barely audible.

[Wolf]

Re: RSS315HF-4 as the anchor of a 3-way???

Dan's HOSS and BassLines have that awesome low end, but he's done both actively, with separate amps. It's really neat to find out how the subs do in a passive XO, and they really do shine.

Pete- the BassLines had TD12H in them, and they were passive.

The 'Blades' had an active RSS265 in the bottom.

Later,
Wolf

[DoubleTap]

Re: RSS315HF-4 as the anchor of a 3-way???

Hey Pete, here's a measurement of the 15W/4831g00 ... is that smooth enough for ya ;)

[Pete Schumacher]

Re: RSS315HF-4 as the anchor of a 3-way???

Hey Pete, here's a measurement of the 15W/4831g00 ... is that smooth enough for ya ;)

Wow . . .

That's the nicest behavior I've ever seen from a midrange of any flavor.

Believe me, I'm having fun auditioning them. :D

Got any off axis data?

And what size baffle is that on?

[Pete Schumacher]

Re: RSS315HF-4 as the anchor of a 3-way???

Pete- the BassLines had TD12H in them, and they were passive.

The 'Blades' had an active RSS265 in the bottom.

Later,
Wolf

Oops, got all them B's crossed up.

thanks for the correction.

[DoubleTap]

Re: RSS315HF-4 as the anchor of a 3-way???

Wow . . .

That's the nicest behavior I've ever seen from a midrange of any flavor.

Believe me, I'm having fun auditioning them. :D

Got any off axis data?

And what size baffle is that on?

Sure Pete, here ya go ;)

http://www.madisound.com/catalog/PDF/15W_4531G00.pdf

[Pete Schumacher]

Re: RSS315HF-4 as the anchor of a 3-way???

Added a bit of padding to the mid/tweet section today. The current implementation on the Scan is a 2nd order HP using 3mH and 120uF and a 1st order LP using .7mH and a 6.2uF plus 4 Ohm zobel. To this, I added 1.2 Ohm in series with the 15ga input inductor.

Tweeter HP is 6uF and .5mH shunt, with 1.2 Ohm in series with the RS28. This combines with the mid for a very wide range overlap centered at 2900Hz, LR2 acoustic slopes.

Woofer XO still 8mH and 100uF, for a total of 11 components so far.

I think I'll build the second XO to match this one to do the stereo voicing with speakers in place.

So far, these are turning out to meet the aural expectations I've had from the beginning.

[Pete Schumacher]

Re: RSS315HF-4 as the anchor of a 3-way???

Another day of listening yesterday. Still haven't quite got the woof/mid XO right. The upright bass just didn't sound "there" like it usually does in Dianna Krall's rendition of "Cry Me a River."

So, back to PCD to see what a slight relaxation of the woofer XO capacitor does. 100uF to 66uF pushes the XO from 200Hz, to 250Hz, with only slight changes to the FR, so in goes the change.

Suddenly, the life has come back into the upright basses!!! The "chesty" feel in voices is better now as well. Now I have to watch the breakup in the RSS more closely as the filter is still only second order. I may have to add a notch to hear for any differences, but that comes later.

Might try just a tad less tweet level as well, but only after a few more hours of listening. Crossover right now is right around 2800, with shallow slopes, and a very wide v-shaped reverse null.

11 components in the XO still.

[davepellegrene]

Re: RSS315HF-4 as the anchor of a 3-way???

Another day of listening yesterday. Still haven't quite got the woof/mid XO right. The upright bass just didn't sound "there" like it usually does in Dianna Krall's rendition of "Cry Me a River."

So, back to PCD to see what a slight relaxation of the woofer XO capacitor does. 100uF to 66uF pushes the XO from 200Hz, to 250Hz, with only slight changes to the FR, so in goes the change.

Suddenly, the life has come back into the upright basses!!! The "chesty" feel in voices is better now as well. Now I have to watch the breakup in the RSS more closely as the filter is still only second order. I may have to add a notch to hear for any differences, but that comes later.

Might try just a tad less tweet level as well, but only after a few more hours of listening. Crossover right now is right around 2800, with shallow slopes, and a very wide v-shaped reverse null.

11 components in the XO still.

Ah! I was wondering what the difference may be in changing woofer/ mid cross from 200 up to 300. I wasn't sure what to listen for.
Dave

[Pete Schumacher]

Re: RSS315HF-4 as the anchor of a 3-way???

Here's what I'm listening to at the moment.

I'm really liking the looks of the transfer functions. XO points are currently at 250 and 2800, second order.

[Jeff B.]

Re: RSS315HF-4 as the anchor of a 3-way???

Ah! I was wondering what the difference may be in changing woofer/ mid cross from 200 up to 300. I wasn't sure what to listen for.
Dave

He didn't change the crossover point from 200 t0 250 as much as he changed the summed level at 200Hz. By lowering it, with the smaller cap on the mid, the crossover shifts higher as a result. The real difference here isn't the change from 200 to 250, it's the fact that he has less combined energy at 200 Hz, which may have been adding some thickness to the vocals. If both a 200Hz and 250Hz crossover are optimized for a flat summation, then I doubt you would be able to tell much difference at all.

[davepellegrene]

Re: RSS315HF-4 as the anchor of a 3-way???

He didn't change the crossover point from 200 t0 250 as much as he changed the summed level at 200Hz. By lowering it, with the smaller cap on the mid, the crossover shifts higher as a result. The real difference here isn't the change from 200 to 250, it's the fact that he has less combined energy at 200 Hz, which may have been adding some thickness to the vocals. If both a 200Hz and 250Hz crossover are optimized for a flat summation, then I doubt you would be able to tell much difference at all.

Ok makes sense on not being able to hear the difference if both are optimized for a flat response. The rest is confussing me. By lowering the cap on the woofer doesn't this add more energy at 200-250Hz. So wouldn't this add more thickness to the vocals?
Dave

[Mayhem13]

Re: RSS315HF-4 as the anchor of a 3-way???

Either way....this is a really great start to an awesome project Pete. What's you listening impressions of the lower midbass of the RS315?

[Pete Schumacher]

Re: RSS315HF-4 as the anchor of a 3-way???

Let me start off by clearing up what I did. The smaller cap value was on the woofer, not the mid, which increased the output in the 200-400Hz range, bringing back the requisite "thickness" to the upright bass and vocals that was missing with the larger cap value, rolling off the woofer a bit too early.

Jeff did indeed have it backward, thinking I was removing "chestiness" when I was actually bringing it up. No big deal. Doesn't change the fact that Jeff is a friggin' genius. ;)

Afterward, I also reduced the midrange cap value, from 125 to 100uF, pushing up the XO point just a bit for the mid. The RSS filling that range just seems to add more life than having the mid cover those lower frequencies. Everything is just coming to life now.

Lower midbass is just scrumtrulescent