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Gestating large sensitive passive 15" augmenting subs


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Its big, its long and fat, a big black freckle and a big hole near one end.

Getting it up once in 11 months is something to write home about?

 

One up, one to go.

 

Well done!

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Just a quick announcement that twins were painlessly born today, to a badly-presented but relieved BioBrian and his wonderful StereoNetter cohorts. I'd really like to gratuitously thank all staff, but

It's an odd experience when I find someone referring to something I wrote that I can't remember.   When you compare different kinds of subs, there are two experiences. The first is the easy

Both boxes now all trimmed, ready for final sand and varnish. Don't think I'll need DuraTex after all...   Worst problem has been lack of handles to move them.   110 kg each, so wi

Must be something in the water. Something arose again today.

 

Had to do different brackets on this box, but experience made this one easier. Well, at least to begin with.

 

1087986471_2ndoneeasier.jpg.0ad4b75899186e22e3023b9900f402b2.jpg

 

Getting it up is one thing, but getting it in was not a given. Bit tricky with that beam, and all the junk to miss.

 

'Creep' range is great for this job - 1st gear would give 200 m per hour at full throttle! But the diesel fumes...

 

465590078_Forkstochainblocks.jpg.c40b43a4692cd79f366860b1aa5e72c2.jpg

 

Transfer from slings to chain blocks, and nearly a case of "there's no backing out from this one".

 

Anyway, symmetry at last - home sweet home :wub:

 

Symmetry.jpg.0665a5bd899ad65edc346ef349169295.jpg

 

I did manage to feed the cables, but it's time to put something else up - my feet.

 

 

 

 

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12 hours ago, almikel said:

no rattles

Good point Mike. Can't be sure until testing, but there is a bit of spring in the brackets, a bit of stretch in the 100mm bolts, and 8mm nylon pads in each corner. May need to clamp the bottom to the plywood-faced wall. Tying down everything else in the space could get interesting.

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On 05/03/2020 at 7:45 PM, BioBrian said:

What's a bit more obvious here are the blips either side of 200 Hz. Maybe these would change with something behind the driver?

They won't be relevant if you use an appropriately steep low pass filter.

If you don't use such a low pass filter.... then you're going to have other bigger problems due to the "multi-source" playing at 200+ Hz.

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I'll be honest, Dave, it's been a struggle.

 

And now the interesting part begins, as you've pointed out.

 

But whatever, I'll have 2 lovely benches and a white beam to live with.

 

And a clear floor area at last, to enjoy (and probably to defend vigorously).

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The system has been put together again now, with a few changes from before.

 

965168435_SystemwithLux.jpg.63eb238920d5be737cca1ffe18e21e9b.jpg

 

My 4-way speakers now have a single Luxman M-900u amplifier driving them; its combination of grunt and finesse are off the scale. The reviews speak of the extraordinary imaging to be heard from this amp; it's something I've never experienced before. Incredible - very very pleased!

 

741921385_CelebrationofLux.jpg.2d1676c4464a705cbc11590b99cf82f7.jpg

 

But why did they only supply one pair of white cotton gloves? The beast weighs in at 48 kg - OH&S alert!

 

The  'Gestie' subs, now up in the wall/ceiling corners behind the listening area, have been interesting to play with. For now, they are just being fed by my 6th of March kanga-filter (roo-dimentary, if that was too obscure) and a 70 W Cyrus integrated amp. When the main speakers are switched off, you can only hear a low grunting, which indicates very effective cutting of high frequencies - enough to relax about that for now, and deal with the more gross issues, "how much is enough", and "are they even in phase, 'coz I can't hear them unless they get 27dB boost".

 

The most important observation so far is that recorded music has a crazy variation in quality and quantity of bass material. "Dead Can Dance - Live" has, to my taste, a ridiculous amount of bass, and the subs only balance the mains (and are still choofing it out) with some cut. Despite the word "Live" in the title, the sound I'm getting has a clarity not remotely possible from a live venue, or at least that's my experience.

 

Some classical tracks need up to 27dB boost* for them to start giving a feeling of warmth; that the subs are actually contributing.

 

[*Edit: this makes no sense to me now, late May - it probably had to do with different ways of labelling gain on different amps and preamps I was using].

 

SO - they are going to need a volume control, readily accessible from the listening position.

 

The nice STX Neutrik Speakon plugs clicked into place in the cabinets - sadly that's a little pleasure I won't be repeating often, as the filters are at the amplifier end of the cables, for easy R & D.

 

There's a curious thing happening with the passive filters, which I'll look into further at some stage. Need more bits - here we go again...

Edited by BioBrian
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19 minutes ago, BioBrian said:

 "Dead Can Dance - Live" has, to my taste, a ridiculous amount of bass, and the subs only balance the mains (and are still choofing it out) with some cut. Despite the word "Live" in the title, the sound I'm getting has a clarity not remotely possible from a live venue, or at least that's my experience.

"In Concert" or "Toward The Within"?

Either way both are "live" and having been fortunate to see them in some of the best venues in the world, I can certainly attest to their "clarity".

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5 minutes ago, BioBrian said:

There's a curious thing happening with the passive filters, which I'll look into further at some stage. Need more bits - here we go again...

That's what it's all about when you do the Hokey Pokey!

Enjoy ?

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19 minutes ago, Hydrology said:

Either way both are "live" and having been fortunate to see them in some of the best venues in the world, I can certainly attest to their "clarity".

Yes, that was certain to get me into trouble, wasn't it? Sorry. But we would both have to compare both, which can't be sorted easily, and I certainly don't want to argue the point. What I was referring to was that in live venues the sound often comes from multiple sources, and arrives out of phase, or with actual echoes, which puts an end to any chance of enjoyment (for me).

 

BTW, and I don't know how to do this adequately, I would like to thank you, and the other members who were so valuable in helping me make this huge amplifier choice.

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  • 1 month later...

Things have settled in a bit. Not enough listening time, and that's getting less likely as winter sets in. Max of 8.8 degrees outside today ?, and minus 2.5 overnight.

 

I'm now using power amps of equal gain: driving the 4-ways, and these Subs, from the same preamp. The balance is OK, with all four 15" drivers getting equal oomph. Even Dead Can Dance! ?

 

The Low Pass filter for these subs is still a birds-nest of coils etc on the bench, at the amplifier end of the speaker cables. It works fine - not much intelligible music gets past them. They just fill in the bottom octave nicely, eg making me aware for the first time that one particular track actually has an organ, which I hadn't realized before. Subtle, as it should be.

 

So I'm still looking at options regarding LP filters. I read the other day Rod Elliot's  article about PLLXOs, in which he basically said that the concept runs out of usefulness when expecting steeper slopes. Something to do with pushing the impedance limitation - we need to bring in opamps to make passive filters work at 24 dB/octave and above.

 

So I was pleased to come across the Xkitz site. I don't know why this hasn't been mentioned before, but it would seem just what I've been looking for. Made in California...

 

https://www.xkitz.com/collections/active-crossovers-and-bi-amplifiers-1/products/linkwitz-riley-2-way-active-crossover-fully-balanced-xover-2b

 

I could get 2 of these, use only half of each (the LP part), add his LPS in a tidy box, and bingo. No more passive horror stories between amp and drivers! Woohoo!

 

I know there are some who think it's a waste of time, no EQ, won't integrate properly with 4-ways, etc, and the only way is DSPeaker or miniDSP etc, but I'm still trying to stay anal-ogue for now, and realize the properties of the driver/box design I've chosen.

 

If anyone can offer helpful comment or experience about the Xkitz gear, I'd love to hear.

Edited by BioBrian
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On 02/04/2020 at 12:51 PM, Auracle said:

That's what it's all about when you do the Hokey Pokey!

Sorry Sam, I never got back to this one. I'll paste the graph from March 6 again here:

 

1121114901_Box2filtermedleyvent12mH-150uF-1R.thumb.JPG.a982df7d8253ea3cdd697ba0777e943e.JPG

 

What bothers me with this passive filter thing is the area between 16 and 30 Hz. You'll notice that the Black line (which bears scarce resemblance to the nice WinISD ones, but doesn't include blending with the vent curve) gives the best 20 Hz response. Only by 1 or 2 dB, but why? As I increase the series induction value from zilch to 22 mH, this area suffers more and more. It also increases the difference in volume between 20 and 50 Hz, which is not what I want from all this effort.

 

Maybe a line-level filter won't do this. Dunno. It may be the reason that I chose 4th order for the 4-way 15" woofers (coil, cap, coil, cap), which kept the mH down for each one, avoiding some of this??

 

 

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On 26/05/2020 at 7:46 PM, BioBrian said:

I know there are some who think it's a waste of time, no EQ, won't integrate properly with 4-ways, etc

I wouldn't say "waste of time" .....  the subwoofer should be quite flat through the part of the passband where you'll want the low pass to operate .... so that will work (filters like this weren't suggested due to opamps).

 

Edited by davewantsmoore
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On 06/03/2020 at 6:54 PM, BioBrian said:

I've seen this before - a "2nd order" electrical setup doesn't equate to a 2nd order acoustic result (12 dB per octave slope). I suspect I'll need more components to make it "4th order", but I'm keen to hear what these guys can "do for me jollies".

?

Looks almost exactly 12dB/octave to me

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On 26/05/2020 at 8:12 PM, BioBrian said:

What bothers me with this passive filter thing is the area between 16 and 30 Hz. You'll notice that the Black line (which bears scarce resemblance to the nice WinISD ones, but doesn't include blending with the vent curve) gives the best 20 Hz response. Only by 1 or 2 dB, but why? As I increase the series induction value from zilch to 22 mH, this area suffers more and more. It also increases the difference in volume between 20 and 50 Hz, which is not what I want from all this effort.

Check the speaker impedance ;)

 

Edited by davewantsmoore
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1 hour ago, davewantsmoore said:

?

Looks almost exactly 12dB/octave to me

I mean the bit that the filter alters: above 50 Hz. 12 dB from 50 to 200 Hz is over 2 octaves, or 6 dB per octave.

 

The part below 50 Hz should be averaged with the vent output (green line) to be more meaningful. I'll do that when time allows - curious.

 

1 hour ago, davewantsmoore said:

we can see that the Zmax of the driver in box, but be somewhere around 50hz.

Not sure what this means, Dave. Is there a word or 2 missing or something?

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On 27/05/2020 at 11:36 PM, BioBrian said:

I mean the bit that the filter alters: above 50 Hz. 12 dB from 50 to 200 Hz is over 2 octaves, or 6 dB per octave.

Yes, it won't make a 12dB/octave filter here, because of the interraction with the rising/falling speaker impedance.

 

When the speaker imedance calms down, (eg. >> 200Hz) you can see that it settles into a 12dB slope.

 

 

On 26/05/2020 at 8:12 PM, BioBrian said:

Maybe a line-level filter won't do this.

Correct, it won't....  because you wont be adding resistance between the amp and the driver (which is the cause of this lump)

 

 

... but if you have you sub LR4 low pass at 60 (or whereever Hz).... and you mains are LR4 high pass at 30 (or similar) .... then the drivers will be out of phase.

 

Of, course, adding a decent low pass filter, will be better than what you have now, so it's worth a go.

Edited by davewantsmoore
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4 hours ago, davewantsmoore said:

adding a decent low pass filter, will be better than what you have now, so it's worth a go.

There have been about 250 views of this thread since I asked the question, and this is all I have to go on.

 

Are you suggesting the Xkitz crossover would be significantly better than continuing on with my good old passive beasties? (At a few hundred bucks and another bout of nail-biting waiting, it's worth asking the question out straight).

 

(Anyone else in, for last words? No obligations, no blame, any comment welcome; PM is fine too, if you're shy).

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5 hours ago, davewantsmoore said:

... but if you have you sub LR4 low pass at 60 (or whereever Hz).... and you mains are LR4 high pass at 30 (or similar) .... then the drivers will be out of phase.

I don't see a problem here, as these subs are literally just doubling the output of the main woofers, which cross at 100 Hz. There is no crossover (as in something with a matching HP filter), just an LP filter. They might cut out a bit lower, that's all. I just wanted it a bit warmer in the bottom, which has been working to plan.

 

In light of that, to avoid phase issues, I should probably just copy the filter from the 15" drivers in the mains, or have the 'knee' just a bit lower. Eg, after measuring the room response, it may be that I could coincidentally reduce a peak around say 80 Hz by placing the -3 dB point a bit lower than it.

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5 hours ago, davewantsmoore said:

Yes, it won't make a 12dB/octave filter here, because of the interraction with the rising/falling speaker impedance.

 

When the speaker imedance calms down, (eg. >> 200Hz) you can see that it settles into a 12dB slope.

I should have put the explanation of the 4 lines here when copying the graph. The blue line, which shows the 12 dB/oct slope, is the effect of the parallel cap added to make the filter "2nd Order". One reason it only starts at 200 Hz is that I need to play with much more capacitance, bringing the 2nd Knee (if that's a thing) back toward 80 Hz, where I want it. (For ref, it was about the 3rd post on page 18).

 

With the 4-way project, I gave it enough time to get this right, having the first coil/cap act together, and the 2nd ones having a 'later knee', more decisively cutting the breakup stuff further up.

 

Maybe a classic Zobel to control the impedance rise would solve this.

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1 hour ago, BioBrian said:

Are you suggesting the Xkitz crossover would be significantly better than continuing on with my good old passive beasties?

What I have said to you in the past (including in this thread) ..... it isn't about passive vs active vs analogue vs dsp.    They're all just tools to achieve a result.

 

If the resulting response is the same among the different methods, they will sound the same.

 

Continuing on with the passives, to me implies either a 1st order or 2nd order low pass roll off.

 

.... but your mains already have a 4th order high pass response.     So they will have different phase rotation (ie. they can't be in phasse over all but a narrow band).

 

Also..... without a steep(er) slope, you won't be able to attenuate the upperbass/mid content from the subs .... whcih will be detrimental (in general), but especially considering their placemnt in your system.

 

 

So, yes.  I'd recommend a 24dB/octave low pass response on your subs....   it matters not how you get it.

 

I'd be the soncerned that the phase of the subwoofers and mains in the octave or so where they overlap, is going to be a long ways off..... but save that for another time.

 

1 hour ago, BioBrian said:

 

(At a few hundred bucks and another bout of nail-biting waiting, it's worth asking the question out straight).

 

(Anyone else in, for last words? No obligations, no blame, any comment welcome; PM is fine too, if you're shy).

 

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1 hour ago, BioBrian said:

I don't see a problem here, as these subs are literally just doubling the output of the main woofers

Not if they are out of phase them them, they're not  ;) 

 

 

1 hour ago, BioBrian said:

, which cross at 100 Hz. There is no crossover (as in something with a matching HP filter)

When I refer to the high pass response I am refering to the LF rolloff, eg. 30ish in your mains speakers..... a bit lower for your subwoofer.    This rolloff is affecting the phase of the driver, and is part of the consideration for having them in phase.

 

1 hour ago, BioBrian said:

In light of that, to avoid phase issues, I should probably just copy the filter from the 15" drivers in the mains, or have the 'knee' just a bit lower. Eg, after measuring the room response, it may be that I could coincdentally reduce a peak around say 80 Hz by placing the -3 dB point a bit lower than it.

I see.  That could be another plan.    If the woofer in the main and the sub have the same low pass response ..... and their high pass response are not too dissimilar ...... then their phase would be equal enough.    Are they the same distance from you?

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1 hour ago, davewantsmoore said:

That could be another plan.    If the woofer in the main and the sub have the same low pass response ..... and their high pass response are not too dissimilar ...... then their phase would be equal enough.    Are they the same distance from you?

Yes. The listening position is not in concrete, but I've spent a while over the last week sorting distances to the mm with a 5.1 setup. I have the LDM on a tripod, so it only took a few seconds to find that the new subs are within 8" of the intended plan (equidistant to the main woofers). That was pleasing.

 

 

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On 28/05/2020 at 1:06 PM, davewantsmoore said:

As you add more series resistance, the speaker response increases in areas where the impedance increases.   That's how I know the impedance is at maximum at ~50Hz, becasue that's where the lump in the response is.

I used DATS to measure the impedance today. This is one sub, measured with and without filter, box in situ, and including the long cable (which measured about the same as the other side, with shorter cable). The filter (green lines) is 22 mH in series, and 150 uF with about 2 Ohm resistor across the driver:

 

image.thumb.png.03df74213c3490b066d8eab9a7d3207c.png

 

So Im confused about what you said.

 

Common knowledge is that a 4 ohm driver is louder than a 8 Ohms driver (but draws more current). That's what seems to be happening here: it's almost down to 4 Ohms about 46 Hz, at its loudest, then gets quieter as the filter 'impedes' the signal more with higher frequencies.

 

BUT below that is a mystery to me. Impedance and loudness / excursion don't seem to match.

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21 hours ago, BioBrian said:

Yes. The listening position is not in concrete, but I've spent a while over the last week sorting distances to the mm with a 5.1 setup. I have the LDM on a tripod, so it only took a few seconds to find that the new subs are within 8" of the intended plan (equidistant to the main woofers). That was pleasing.

8" is close enough.

 

Although I would have thought that the low pass filter on the woofer in your main speakers was too high in frequency (eg. well over 100hz).  ?‍♂️

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4 minutes ago, BioBrian said:

Common knowledge is that a 4 ohm driver is louder than a 8 Ohms driver (but draws more current).

Most people seem to misunderstand this.

 

It "draws more current" for the same voltage.   All else equal, to move the same, the same amount of current flows in drivers of diffrnt impedances.

 

You can see that for a constant voltage..... that more current will flow at 50Hz (due to the lowered impedance) ..... more current = more movement = more SPL.

 

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12 minutes ago, davewantsmoore said:

Most people seem to misunderstand this.

 

It "draws more current" for the same voltage.   All else equal, to move the same, the same amount of current flows in drivers of diffrnt impedances.

 

You can see that for a constant voltage..... that more current will flow at 50Hz (due to the lowered impedance) ..... more current = more movement = more SPL.

I think that's what I said. Mine drops to 4 Ohms around 50 Hz, and it's there that it's loudest. Then gets quieter as the impedance rises above that.

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4 and 8 ohm drivers will play the same SPL when given the same amount of current.

 

One just receives more current than the other, when voltage is held constant.

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@davewantsmoore   

On 29/05/2020 at 7:19 PM, davewantsmoore said:

4 and 8 ohm drivers will play the same SPL when given the same amount of current.

 

One just receives more current than the other, when voltage is held constant

Power = volts x amps  

 

" 4 and 8 ohm drivers will play the same SPL, when given the same amount of power "  ?

 

 

 

 

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9 hours ago, Dirkgerman said:

@davewantsmoore   

Power = volts x amps  

" 4 and 8 ohm drivers will play the same SPL, when given the same amount of power "  

Yes.... but people get confused due to the constant voltage nature of typical speaker testing / measurement / spec-ing

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I find constant-voltage testing to be de-confusing. It's not as if we are going to run out of current here. There's about 400 times what we need,  on tap.

 

I did these the other day to get an idea of sensitivity - not saying the test method is perfect, but these are what Omnimic showed when placing the microphone 1 metre from each speaker, using 2.89 Volts (the nearest to 2.83 my preamp would allow).

 

Black is a "Gestie" sub up on the wall, mic 1m, 2.89V sine sweep, no filter applied.

Red is one of my pyramid 4-Ways, mic 1m on mid-tweeter axis, 2.89V sine sweep.

 

1997496930_Gestblack4Wred1mbothinsitu2_89V.thumb.JPG.6c4f8d326bfb9f8f75bbcb2e7eaa5ca5.JPG

 

 The dip at 161 Hz would be a floor bounce from the 15" and 8" woofers (no floor padding), which would not be there at the seated position.

 

I'll have to try what happens at the seated position, with individuals / pairs / all 4 going - could be interesting.

 

 

Edited by BioBrian
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On 28/05/2020 at 1:06 PM, davewantsmoore said:

As you add more series resistance, the speaker response increases in areas where the impedance increases.   That's how I know the impedance is at maximum at ~50Hz, becasue that's where the lump in the response is.

In Brian's Graphs, the lump in response at ~50Hz is mainly caused by the reactance of the large value inductor (in the LP filter) reacting with the capacitive component of the impedance above the impedance peak of ~30Hz

 

It is not unlike using a large a large value cap to provide bass boost in a sealed box, where the added capacitance reacts with the inductive component below the impedance peak.

 

 

 

 

Here is a sample graph showing the inductive and capacitive components of a complex impedance

speaker.jpg

Edited by afa
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11 minutes ago, afa said:

In Brian's Graphs, the lump

Indeed.

It's probably a bit confusing to have said "resistance".... sometimes I don't choose my words very well.

 

See that the bump is between 30 and 70Hz.   With the peak increase in SPL just below 50Hz.   This corresponds to the ~400Hz region on your chart.   "Resistive".

 

 

 

 

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Not wanting to nit pick? 

But you said

On 28/05/2020 at 1:06 PM, davewantsmoore said:

That's how I know the impedance is at maximum at ~50Hz,

Whereas Brians graph shows the impedance peaking at  ~30Hz

 

On 29/05/2020 at 6:52 PM, BioBrian said:

 

image.thumb.png.03df74213c3490b066d8eab9a7d3207c.png

 

cheers,

 

 

 

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Maybe when my ears have recovered a bit? Feeling a bit shredded.

 

Too cold to go up there again today.

 

The neighbours'd probably agree ?.

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Should find good, even attenuation up and down the octaves, is a wonderful thing !~! (yes it would be chilly on site, brr, the Mtn)

 

Edited by Dirkgerman
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Why? Well I was expecting this to be a bit shocking - my first try at room measurement - I admit I didn't really want to find out, after reading of everyone else's ventures.

 

For a while now, I've stopped recording the volume level, and just bring it up so the loudest part of the graph is around 90 dB. But I found out that multiplying this by 4 large speakers was probably not a good idea. Those "Wheep, wheep" noises at full range and that output are pretty painful.

 

All were taken at 1.2m above floor - my listening chair/ear height. First, I got equidistant between mains and subs, and from that reference point, came forwards incrementally a couple of feet. That gave indication of how much variety to expect initially. Wow. No wonder I bob my head around a lot.

 

So I got some reliable traces, enough to show I'm not cheating here, then at the end I switched off the sub amp, and did another sweep.

 

131535987_Barn1stroom.thumb.JPG.2f66b8f20b010c257f14f18df7599d04.JPG

 

Sorry it's a bit busy. I left the phase line in for the black trace - sure it can explain a few things.

 

Firstly RED - this is what us softies have been listening to, insisting on admiring the view, before the Gesties started jesting along.

BLUE - same thing - just the 4-ways, but with the Rolladoor closed. What a price, for a few more dB of the goods.

BLACK - door open, but Gesties filling in a few holes, just like the initial wish. Was it all worth it? Pretty flat from 12.5 to 50 Hz - enough to retire on??

GREEN - door shut, all still firing. Bass not as even, but I like how shutting the door heals some of the 215 - 267 Hz problem.

 

Lots to think about.

 

 

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      Hey guys,
       
      Got handed down a sick sound system from a relative that's downsizing, and he said he's not sure whether or not the subwoofer actually works. He's not a massive hifi/electrical guy so it's up to me to diagnose it. For now I just need help knowing what the correct way to connect it is, so I can know whether it actually works under normal conditions, and if not then I'll open it up and get the multimeter out. 
       
      Receiving this system is what spurred me on the join this site because I really want to optimise it and learn how to use it well, because I don't have any hardcore hifi experience, just tinkering with cheap junk over the years.
       
      So far I've just tried connecting the amp's subwoofer port directly to the "low level input" with a 1 to 2 RCA cable, and didn't get anything. Fuse is intact.
       
      So:
      Looking at the photos of the inputs, are this sub and amplifier actually compatible, and if so, what's the best way to connect them?
       
      Should I care about the speaker out part on the sub or just throw the speakers directly onto the amplifier?
       
      Also, can someone give me a rundown on the gain/Freq knobs as well as the on/auto/off and phase switches? Like, I know what gain is from playing my guitar, and I understand that the frequency knob will be probably focusing the sub on a particular frequency to thump out or isolate, but I don't know what kind of range I want to keep it on for it to be good. Absolutely no clue what the phase bit is for.
       
      Cheers, and happy listening


    • By PaddyMcD
      Item Condition: Used Shipping Options: Pickup available and you can audition.,Shipping is available at agreed cost. Suburb or Town: Sydney State: NSW Payment Method: Cash, Paypal Reason for selling: Change Subwoofer has a ding on the left corner (pictured) from removal company. Doesnt effect performance. Mediabridge ULTRA Series Subwoofer Cable (2M) included. 
       
      Further information:
       
       Polk Audio Powered Subwoofer PSW303

      * video-shielded

      * slot-loaded enclosure

      * 100-watt RMS amp

      * 8" front-firing, long-excursion driver

      * frequency response 35-160 Hz (-3dB)

      * continuously variable 60-160 Hz crossover

      * unfiltered LFE input for 5.1 bass

      * line-level and speaker-level inputs

      * speaker-level output

      * volume control

      * phase switch

      * auto on/off

      * real wood veneer

      * 11-7/16"W x 12-3/8"H x 17-7/8"D

      * warranty: 5 years woofer, 3 years amplifier
       




    • By Shane Stephenson
      Item Condition: Near mint condition. Shipping Options: Pickup available and you can audition. Suburb or Town: Herne Hill Geelong State: VIC Payment Method: Cash Reason for selling: Too big and powerful for my room. Hi all up for sale is my SVS ultra 16 PB subwoofer. This unit is in mint condition with very little used would suit somebody wanting to buy new. It is 6 months old and has 4 1/2 years warranty remaining.
      This thing is ridiculous as all the reviews show. You need to make sure everything's tied down around your house because stuff will start falling off the shelves. Sealed up it produces amazing chest-thumping bass for 2 channel Hi-Fi listening.  And with the plugs released gets down comfortably into the mid teens shaking the dust off your ceiling fans. It literally makes your house resonate. Must be heard to be believed. It's just too much for my house and my listening room. But at the time I purchased this my eyes were bigger than my stomach. Grab yourself an end game sub for a very reasonable price. It's black Ash and I have the brand new remote control still in the Ziplock bag. There are no marks or damage on the subwoofer anywhere l have the inner box but not be outer cardboard.
       
      Photos:
       
      PLEASE READ
      If you include any reference to pricing whatsoever in this section (excluding RRP), your ad will not be approved If you are advertising multiple items, you must post one bulk price only, or post seperate ads for each item If you don't include photographs of the actual item being sold, your ad will not be approved You understand that a reasonable donation for selling fees is expected upon successful sale of your item
      - if you have previously sold items and not made a donation, your advertisement may not be approved.





    • By Michael Lee
      Item Condition: Good used Shipping Options: Pickup available and you can audition. Suburb or Town: 2570 State: NSW Payment Method: EFT Reason for selling: Redundant A good surround sound speaker starter package. The sub has recently been serviced. Further information:
       
      Photos:
       
      PLEASE READ
      If you include any reference to pricing whatsoever in this section (excluding RRP), your ad will not be approved If you are advertising multiple items, you must post one bulk price only, or post seperate ads for each item If you don't include photographs of the actual item being sold, your ad will not be approved You understand that a reasonable donation for selling fees is expected upon successful sale of your item
      - if you have previously sold items and not made a donation, your advertisement may not be approved.





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