highfigh

highfigh

Audioholic Slumlord
I'll get that and run the tests again. Thanks.



But 2 drivers in one box means 1/4 of the power, right?

I'm going to ask you to help me figure out what to do with them, even if it's only for car audio, after I figure out a few things and get highfigh's clay recommendation to test against what I've done so far.

Rob (anunaki) pointed out that they might be one-note wonders.

I gotta go mess with routers and I gotta say, that's my least favorite tool. Anything spinning at 30,000 RPM is just wrong.
Sealed box, if they're suitable for that, means the response will cover a broader range than a one not wonder which is always ported, the port frequency is very close to the Fb and does almost nothing outside of that peak. Great for some music, useless for everything else.

Two drivers in series will produce the same SLP as one because the voltage has been halved, but the cones move more air, in parallel, the impedance is halved AND the cones produce more air, so it's like quadrupling the power with a single driver. However, you need to make the amplifier happy and the Vb will be larger, whether sealed or ported.

How do you make a router spin at 30K RPM when it has all of those cables connected to it?

Oh, right.......

Take the cutter to the material and it's safer than taking the material to the cutter- I made a mistake once and narfed my left index finger. Not bad, but it was a wakeup call. Next time I used it, I walked up, paused and said "So, we meet again".
 
TLS Guy

TLS Guy

Audioholic Slumlord
I'll get that and run the tests again. Thanks.



But 2 drivers in one box means 1/4 of the power, right?

I'm going to ask you to help me figure out what to do with them, even if it's only for car audio, after I figure out a few things and get highfigh's clay recommendation to test against what I've done so far.

Rob (anunaki) pointed out that they might be one-note wonders.

I gotta go mess with routers and I gotta say, that's my least favorite tool. Anything spinning at 30,000 RPM is just wrong.
Two drivers gives you a gain of 3 db just because their are two drivers. If the drivers are wired in parallel that gives you another 3 db increase in sensitivity so now we have 6db. Now since there are two drivers there will be twice the power handling, so another 3 db. Total increase is 9 db.

Now usually low Qts drivers are the least likely to be one note wonders. Just looking at the numbers I suspect unequalized F3 will be around 60 Hz in a sealed box. So the question becomes whether the drivers can take the power required to have reasonable output at 20 Hz. Since they were for car use, which is not the same as a room, that might be questionable. Can you find the power handling of those drivers and xmax? If you can find that, I can do a model for you and let you know if they would be any use in a home system. Usually car drivers fall short of the mark in domestic systems.
 
Alex2507

Alex2507

Audioholic Slumlord
the question becomes whether the drivers can take the power
They can take all the power I can afford. Even the Crown big boy is ~ six something. I don't currently own anything even remotely capable of outdriving them. The car amp is 750 watts @ 4 Ohm @1% distortion between like 10 and 250 Hz. It drove 1 driver w/ the voice coils wired in series in a sealed box of 2 to 3 cu ft. Probably 3.

Can you find the power handling of those drivers and xmax?
Probably not. The communication the previous owner had with the manufacturer likened these drivers to another obscure RF model that I couldn't find any info on and there are no markings. Here's the thread I had going about it:


It said 2000 watts w/ 4000 watt peaks.

Is there a practical way to check the xmax?

I can do a model for you
Before you do that, let me verify the numbers and test both drivers.

Also, I need a chance to figure out how to do the scren shot thing to post T/S parameters and graphs instead of actually taking pic's of my screen. It's like Fred Fintstone lives in that part of my brain.
 
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TLS Guy

TLS Guy

Audioholic Slumlord
They can take all the power I can afford. Even the Crown big boy is ~ six something. I don't currently own anything even remotely capable of outdriving them. The car amp is 750 watts @ 4 Ohm @1% distortion between like 10 and 250 Hz. It drove 1 driver w/ the voice coils wired in series in a sealed box of 2 to 3 cu ft. Probably 3.



Probably not. The communication the previous owner had with the manufacturer likened these drivers to another obscure RF model that I couldn't find any info on and there are no markings. Here's the thread I had going about it:


It said 2000 watts w/ 4000 watt peaks.

Is there a practical way to check the xmax?



Before you do that, let me verify the numbers and test both drivers.

Also, I need a chance to figure out how to do the scren shot thing to post T/S parameters and graphs instead of actually taking pic's of my screen. It's like Fred Fintstone lives in that part of my brain.
These are the best specs I can find. So that would make it high Qts, so it likely is a one note wonder, like most car subs.
 
highfigh

highfigh

Audioholic Slumlord
They can take all the power I can afford. Even the Crown big boy is ~ six something. I don't currently own anything even remotely capable of outdriving them. The car amp is 750 watts @ 4 Ohm @1% distortion between like 10 and 250 Hz. It drove 1 driver w/ the voice coils wired in series in a sealed box of 2 to 3 cu ft. Probably 3.

Probably not. The communication the previous owner had with the manufacturer likened these drivers to another obscure RF model that I couldn't find any info on and there are no markings. Here's the thread I had going about it:


It said 2000 watts w/ 4000 watt peaks.

Is there a practical way to check the xmax?

Before you do that, let me verify the numbers and test both drivers.

Also, I need a chance to figure out how to do the scren shot thing to post T/S parameters and graphs instead of actually taking pic's of my screen. It's like Fred Fintstone lives in that part of my brain.
Is this the same woofer? The link shows Xmax of 15.5mm.


There is a way to find Xmax- IIRC, it was described in The Loudspeaker Design Cookbook.
 
Alex2507

Alex2507

Audioholic Slumlord
These are the best specs I can find. So that would make it high Qts, so it likely is a one note wonder, like most car subs.
Fs, Qts and Vas don't line up with my test results or with Highfigh's Linked spec's and the linked spec's don't line up with each other. At least my spec's are without question for these drivers.


Is this the same woofer? The link shows Xmax of 15.5mm.


There is a way to find Xmax- IIRC, it was described in The Loudspeaker Design Cookbook.
I think all three subs might be in the same "family" of subs but the term prototype thrown at my drivers tells me either somebody was blowing smoke up the previous owners @ss or I just might have something worth while.

I got past my router phobia and now have holes out the ying yang. Gotta do something to all this wood to sort of seal it up, even if just a little. Sanding first, then a wipe w mineral spirits and then ...
 
highfigh

highfigh

Audioholic Slumlord
Fs, Qts and Vas don't line up with my test results or with Highfigh's Linked spec's and the linked spec's don't line up with each other. At least my spec's are without question for these drivers.

I think all three subs might be in the same "family" of subs but the term prototype thrown at my drivers tells me either somebody was blowing smoke up the previous owners @ss or I just might have something worth while.

I got past my router phobia and now have holes out the ying yang. Gotta do something to all this wood to sort of seal it up, even if just a little. Sanding first, then a wipe w mineral spirits and then ...
If you were a manufacturer, would you release prototypes to the general public? I wouldn't.

Were those specs close? I wouldn't expect them to be exactly the same across the board unless they control the manufacturing process to a fine degree but they really should be similar. Also, they probably used LEAP when they tested the drivers, you're using John Murphy's part and software and some variances should be expected.

"seal it up"- do you mean the wood grain? What will you use for the finish? Do you want a completely smooth surface? For that, I have used fine ScotchBrite dampened with something (sometimes Shellac, sometimes Poly) and sanding in circles. The ScotchBrite smooths/sands the wood, the finishing material mixes with it and creates a slurry that fills the pores. Once it's apparent that the pores have been filled, it can dry and be sanded flat & smooth before applying more finish. Much faster than just putting a coat on, letting it dry and seeing that another coat is needed- this way, it's one coat, it dries once and you're ready for the top coat much sooner. Obviously, practicing on scrap is a good idea. I have used satin poly, but mostly it was MinWax fast drying floor Poly because it's made to be more durable- if you want to spray it, go ahead and thin it 50% with Naptha. I sprayed my kitchen cabinets and they dried completely smooth.
 
Alex2507

Alex2507

Audioholic Slumlord
would you release prototypes to the general public?
It came from a dealer that entered auto shows with the equipment. Eventually it got passed along to the sparky that I bought it from.

Were those specs close?
I didn't think so.

do you mean the wood grain?
I mean what happens to raw wood when you put a coat of poly on it. I could have used a natural stain/sealer but I couldn't find that can and the poly was right there so ...

Do you want a completely smooth surface?
Sure ... but I don't want to work for it. :) If I get tired of the Maple veneered ply, I'll paint it flat black with a roller like I did the record player stand and the bass cabinets for my speakers. I'm not producing fine finishes ... I'm not even producing finishes as fine as I'm capable of producing. I might go through the hassle of adding a really cool piece of Walnut Veneer if I can work it into a nice design scheme but that stuff is quickly becoming less and less important to me. I need it to look 'decent', not magnificent. :)
 
highfigh

highfigh

Audioholic Slumlord
It came from a dealer that entered auto shows with the equipment. Eventually it got passed along to the sparky that I bought it from.



I didn't think so.



I mean what happens to raw wood when you put a coat of poly on it. I could have used a natural stain/sealer but I couldn't find that can and the poly was right there so ...

Sure ... but I don't want to work for it. :) If I get tired of the Maple veneered ply, I'll paint it flat black with a roller like I did the record player stand and the bass cabinets for my speakers. I'm not producing fine finishes ... I'm not even producing finishes as fine as I'm capable of producing. I might go through the hassle of adding a really cool piece of Walnut Veneer if I can work it into a nice design scheme but that stuff is quickly becoming less and less important to me. I need it to look 'decent', not magnificent. :)
If you use Shellac as your first/filler coat, it's not much work to fill the grain, especially on a closed pore specie like Maple. If you can spray, it's even less work- the poly that I thinned with Naptha dried totally flat and it filled the pores in one coat.
 
Alex2507

Alex2507

Audioholic Slumlord
If you can spray,
I could. I have. But I don't want to do it again. I'm okay with not turning out that level of finish. The last time I bought poly it was a satin sheen to help hide my mistakes. Same goes for the flat black Rustoleum for the speaker cabinets. Turning my friend's dusty workshop into a acceptable space to spray in isn't practical with it being 40 miles away. Keep in mind that this is sort of a sow's ear into a silk purse operation with the materials just being what was laying around. It's starting life out as 'used'.

It's time to start thinking about grills and magnets. I hate ordering all that stuff because it always turns into a hundred dollar order. I've got the front face cut. I thought I boned it on the first cut so I was able to relax on the rest of the cuts 'cause it was already boned but it turned out to be okay and the piece came out mint. I rule. :D
 
highfigh

highfigh

Audioholic Slumlord
I could. I have. But I don't want to do it again. I'm okay with not turning out that level of finish. The last time I bought poly it was a satin sheen to help hide my mistakes. Same goes for the flat black Rustoleum for the speaker cabinets. Turning my friend's dusty workshop into a acceptable space to spray in isn't practical with it being 40 miles away. Keep in mind that this is sort of a sow's ear into a silk purse operation with the materials just being what was laying around. It's starting life out as 'used'.

It's time to start thinking about grills and magnets. I hate ordering all that stuff because it always turns into a hundred dollar order. I've got the front face cut. I thought I boned it on the first cut so I was able to relax on the rest of the cuts 'cause it was already boned but it turned out to be okay and the piece came out mint. I rule. :D
You can spray outside and I'm seeing tents sold that are meant for finishing, too. Also, with the harder finish provided by high gloss coatings, wet sanding the flaws out and top-coating with satin is a pretty quick way to get a smooth surface. I have used sandpaper, ScotchBrite and other materials to decrease the gloss, depending on the material. Once, I was working with shellac and after the last step, it looked like water, which was far too glossy- I used a paper towel to soften the look before waxing.
 
Alex2507

Alex2507

Audioholic Slumlord
Okay, so here ...


It looked like this earlier.


... and the panels:


The inside of the back:


I ended up turning the gains up 7 db on the sub to match the mains.

I had the drivers sitting on the desk, plugging the pole piece vent when I took the measurements. I quickly checked them the right way and saw the Vas was up around 2.0 cu ft and the other parameters were within around 25% of the previously stated values ... so ... nothing blew up cranking out Money For Nothing.

EDIT:

BTW, that's that little phono pre-amp sitting under the The Steel. :)

It WAS suppose to get feet to take it at least a little off the floor but the pre-amp fits too nice.

... and I added most of the stuffing from the other cabinet.
 
Last edited:
D

Danzilla31

Audioholic Ninja
Okay, so here ...


It looked like this earlier.


... and the panels:


The inside of the back:


I ended up turning the gains up 7 db on the sub to match the mains.

I had the drivers sitting on the desk, plugging the pole piece vent when I took the measurements. I quickly checked them the right way and saw the Vas was up around 2.0 cu ft and the other parameters were within around 25% of the previously stated values ... so ... nothing blew up cranking out Money For Nothing.

EDIT:

BTW, that's that little phono pre-amp sitting under the The Steel. :)

It WAS suppose to get feet to take it at least a little off the floor but the pre-amp fits too nice.

... and I added most of the stuffing from the other cabinet.
Great job! So how does it sound? You said your using it mainly for music right?
 
TLS Guy

TLS Guy

Audioholic Slumlord
Okay, so here ...


It looked like this earlier.


... and the panels:


The inside of the back:


I ended up turning the gains up 7 db on the sub to match the mains.

I had the drivers sitting on the desk, plugging the pole piece vent when I took the measurements. I quickly checked them the right way and saw the Vas was up around 2.0 cu ft and the other parameters were within around 25% of the previously stated values ... so ... nothing blew up cranking out Money For Nothing.

EDIT:

BTW, that's that little phono pre-amp sitting under the The Steel. :)

It WAS suppose to get feet to take it at least a little off the floor but the pre-amp fits too nice.

... and I added most of the stuffing from the other cabinet.
That looks really nice. How does it sound? In other words, I just hope I did not screw it up for you!
 
Pogre

Pogre

Audioholic Overlord
Okay, so here ...


It looked like this earlier.


... and the panels:


The inside of the back:


I ended up turning the gains up 7 db on the sub to match the mains.

I had the drivers sitting on the desk, plugging the pole piece vent when I took the measurements. I quickly checked them the right way and saw the Vas was up around 2.0 cu ft and the other parameters were within around 25% of the previously stated values ... so ... nothing blew up cranking out Money For Nothing.

EDIT:

BTW, that's that little phono pre-amp sitting under the The Steel. :)

It WAS suppose to get feet to take it at least a little off the floor but the pre-amp fits too nice.

... and I added most of the stuffing from the other cabinet.
That actually looks pretty cool. We all wanna know how it sounds!
 
Alex2507

Alex2507

Audioholic Slumlord
So how does it sound?
How does it sound?

FROM LAST NIGHT:


A lot less noticeable than the original enclosure.

The first check was not with my ears but my fingers. I had to touch 'em to make sure they were firing. Then I cranked it up 5 db at normal-ish listening levels. Then 10db. I mean I could hear it but it just wasn't ... what I'm use too (or is that used too?).

Anyway the Rat Shack analog SPL meter and test tones raised the sub 7 db from where the old enclosure had it, to come up to the level of the mains. Dennis said the mains are good to ~45 Hz (2 cu ft sealed enclosure for a 10" driver).

Uhmmm ... the memory setting for music is 3, which skips dynamic range control and sends sub frequencies to both the mains and sub from a 60 Hz cross. Running the test tones shows output which you can obviously hear.

I only blared a couple of songs from BSA's Plex collection. Personal Jesus by Depeche Mode at ~94 db and then the into for Money For Nothing at something approaching 100 db. Aside from it being heaven, I can't really comment on the sub. Like you can't pick a spot in the music and say 'yep, that's the sub'.

FROM THIS MORNING:

It's been so long since I played a disc but this morning I dug out the Brothers in Arms SACD. That crosses at 100 Hz so it gives the sub a little more to do. Bass Management settings are done in the player. Now I have to check those settings with a calibration ... I'm terrible at no.1 setting things up and no.2 quick listening impressions. The SACD player brought the sub level up 12 db. I had the room to go up 12 db because the previous subs on that player had the mains turned all the way up and the sub turned all the way down. So I think I may have overstuffed it ... critical damping (?) ... is that the term? Maybe moving the drivers 16" apart caused a loss of sensitivity? Not an issue due to normal listening levels and a beefy enough amp sections.

I think the Denon DVD player went up 12 db vs the receiver's 7 db because it handled up tp 100 Hz and didn't send LFE to the mains as the rec'r would have. That make sense? Bearing more of the load, losses would be greater? Anyway, once I got over being completely clueless about what I was hearing and got it set up right ... well, here ... let me explain what had me duped at first. The low cross of 60 Hz being sent to both mains and sub meant I was getting some bass and I could hear bass and I could feel the drivers moving. That left me listening to everything else in stupified amazement. Everything else really does sound good so that's all good but then the sub got turned up 7 db based on the rec'r's test tones. Then good was better.

Moving onto the SACD the same thing happened, it took me maybe 10 or 15 minutes to realize I needed to check those levels. That difference was way more pronounced as everything below 100 Hz suffered the 12 db loss which would all come from the sub.

Now that this actually does sound as right as it can sound ... oh hot f^%&, it's the 4th, we're watching the dog, I can randomly blare music when the girl takes him out for walks and today of all days ... they're already listening to sh!t explode.

I'm not a bad neighbor, I'm an audioholic.


The back needs the same nosing and then both need a finish. That's just stain on Cherry. Maybe a little routering but here's the thing: It looks better than okay and it's in and now that I've got Sheryl Crow's Rockin' The Globe Live playing some other stuff that I'm pretty familiar with ... coupled with the fact that now it's about a million pounds, it's gonna stay put for a while. I can tell by the way the bass comes in at the beginning of track 4 and it's actually her playing the bass guitar on that one ... well, it's just lovely. I'll eventually get around to playing The Wall Flower's One Headlight and Wycliffe Jean's Juantalamera to further check for detail and brute force but I don't have any doubt's about capability.

I think the placement is perfect. It all sounds like all the sound is coming from the same place. Center to center the two sub drivers are 28" apart. Room response seems pretty even. It was good with the other enclosure as well from the same spot.

I dunno ... I like it ... lot. My g/f? From down the building hallway on her way back from walking the dog? Not so much. "I could hear that from down the hallway. Turn that down. Waddaya think, you're 15?" Now I'm gonna ask her, "yeah, but how did it sound?" :rolleyes:

Yep, The Chili Peppers belting out Raindance Maggie upwards of 90 db was effortless. I thought with Sheryl Crow that it just seemed like the bass guitar was a little more realistic, showing a little more detail but The Chilis have that freak of nature, Flea, for a bass guitarist. There's more detail. This is back on the rec'r's bass management. Either bass management system sounds great. Once I find my Wallflowers CD, I'll be able to tell one last thing I know to look for regarding the ability to show detail down low.

Finish wise it's presentable ... for an amateur (and it's still not done). Sound wise, this worked out. Looks wise, I guess I'm proud of it if I'm posting pics of it. But back to sound wise, I wonder how long it will be before this is the new normal. Right now I'm either hyper aware of anything that even remotely resembles bass or simply delighted by the new and improved bass.

Bottom line is that I gotta go hang out with the girl and the dog, plan food, check the weather etc. Me and the sub are going to be thinking about each other though. It's tough walking away from it but I'm hungry. :D
 
Pogre

Pogre

Audioholic Overlord
Finish wise it's presentable ... for an amateur (and it's still not done). Sound wise, this worked out. Looks wise, I guess I'm proud of it if I'm posting pics of it. But back to sound wise, I wonder how long it will be before this is the new normal. Right now I'm either hyper aware of anything that even remotely resembles bass or simply delighted by the new and improved bass.
Well I think it looks pretty cool. I'm feelin' ya on whether the new normal is better or not. Every time I make a change or recalibrate it takes me a couple of days to realize it either sounds just as good, if not better or for me to simply adjust to the change. It almost always sounds worse to me when I first finish up because I'm tired and cranky from dealing with it for the last 2 hours. Then the next day it sounds awesome and I haven't touched anything.
 
Swerd

Swerd

Audioholic Warlord
FROM LAST NIGHT:

A lot less noticeable than the original enclosure.

The first check was not with my ears but my fingers. I had to touch 'em to make sure they were firing. Then I cranked it up 5 db at normal-ish listening levels. Then 10db. I mean I could hear it but it just wasn't ... what I'm used too.
If you're actually aware of hearing it, you've got it too loud, or it's a poor design, resonating because of high Q. That's how good sub woofers should sound … another good sub woofer alignment from TLS Guy.

Play the same music passage with the sub woofer switched off and on. How does it sound?
 
Pogre

Pogre

Audioholic Overlord
If you're actually aware of hearing it, you've got it too loud, or it's a poor design, resonating because of high Q. That's how good sub woofers should sound … another good sub woofer alignment from TLS Guy.

Play the same music passage with the sub woofer switched off and on. How does it sound?
Exactly. If I'm listening to something that doesn't have a lot of deep bass (which is a good chunk of my music) it's really hard to tell a difference with the subs on or off. The difference is subtle and comes across more as sounding bigger with more texture and weight, not necessarily just "more bass". They should not draw any attention to themselves unless you want 'em to.
 
Alex2507

Alex2507

Audioholic Slumlord
I'm feelin' ya on whether the new normal is better or not.
That's not what I meant. It's not normal yet, it's still special. Maybe I used the term wrong. At some point the SQ improvement will get noticed less as I become use to it.

For the first few years after getting SongTowers in the living room I was frequently surprised by how nice they sound. Now their SQ is on my radar like once or twice a week.

Play the same music passage with the sub woofer switched off and on.
The difference would depend on which of the 3 bass management setting were in use. I don't use the LFE to sub+mains setting unless I'm seriously listening and with that one, it's hard to tell the difference. LFE to sub only from a 60 Hz cross is instantly disappointing when you know the bass is suppose to be there. From the fixed 100 Hz cross of the DVD player, turning off the sub is about criminal.

With the previous cabinet I spent time listening to different xo points, LFE to sub -vs- sub+mains and subwoofer phase. That's what lead to a memory setting for regular TV and one for music.

Right now time is kinda scarce. Work starts up for me tomorrow. Of course my tools are scattered across creation and my regular life needs attention.

You said your using it mainly for music right?
That's what I care most about but the TV gets plenty of use. That's why there's a bass management setting with dynamic compression and the LFE being sent to just the sub which can be turned off at the amp for night time viewing.

I just hope I did not screw it up for you!
:) Hardly.

With the help of a handful of people I've got a couple of fine sounding systems. Getting the bass needs met and under the control of suitable alignments, with whatever drivers I got my hands on, is solely to your credit.

This has been an incredible PITA that I really hated about halfway through. It just seemed like laminating some Formica to some pre-cut 12" wide boards wasn't a big deal, cut a few miters, add some cleats ... badda bing, right? Wrong. Just because I can do this doesn't mean I'm good at it. It just means that I'm better at it than someone who actually can't do this due to lack of tools and no experience with woodworking.

I don't care if I never see another clamp or another glue bottle again.

But between the sound and 'the look', I'm glad that past Alex built that for present Alex.
Future Alex should be pretty happy too.

Thanks again.
 

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