Ported vs. Unported speakers

[playdough]

9 hours ago, frednork said:

yep sure, will pm to organise. You might have to turn it down as the mic will only do 140db

Don't forget your ear muffs, might be a tough day  

[March Audio]

2 hours ago, playdough said:

Don't forget your ear muffs, might be a tough day  

Basic inverse square law means that in free field conditions 123dB at 15m equals >146dB at 1m.

 

What's the sensitivity of these speakers? Would be interesting to calculate how much power is required to hit 146dB.

Edited November 4, 2023 by March Audio

[joz]

10 minutes ago, March Audio said:

Basic inverse square law means that in free field conditions 123dB at 15m equals >145dB at 1m.

 

What's the sensitivity of these speakers? Would be interesting to calculate how much power is required to hit 145dB.

 

They are active.

[March Audio]

7 minutes ago, joz said:

 

They are active.

 

Yes, but the drivers still have a sensitivity rating.

[joz]

6 minutes ago, March Audio said:

 

Yes, but the drivers still have a sensitivity rating.

 Ok yes, but I actually have no idea about the sub drivers, the rest were part of the Scanspeak illuminator series at the time.

I'll try to find the subs sensitivity from Stuart @SGR Audio

Edited November 4, 2023 by joz

[March Audio]

51 minutes ago, joz said:

 Ok yes, but I actually have no idea about the sub drivers, the rest were part of the Scanspeak illuminator series at the time.

I'll try to find the subs sensitivity from Stuart @SGR Audio

 

Just as an example (rough figures again) if the sensitivity was 110dB for 1 watt 1m,  to hit 146dB you would need 4kW.  

 

If it were 107dB, you would need 8kW, 104dB 16kW etc.  Most large sub drivers are in the 96dB to 100dB region.

 

All I'm saying is that 123dB at 15m seems unlikely.  1.5m OTOH possible. I just think some numbers may have been mixed up.

Edited November 4, 2023 by March Audio

[playdough]

31 minutes ago, March Audio said:

All I'm saying is that 123dB at 15m seems unlikely.  1.5m OTOH possible. I just think some numbers may have been mixed up.

Hi, it's possible, was a long time ago and second hand information.

Something about a sore ass from a non stop drive from Bathurst came up as well. 

 

We can maybe agree Joe has one of the loudest domestic HiFi's ever and loves to arc them up.

[joz]

1 hour ago, March Audio said:

 

Just as an example (rough figures again) if the sensitivity was 110dB for 1 watt 1m,  to hit 146dB you would need 4kW.  

 

If it were 107dB, you would need 8kW, 104dB 16kW etc.  Most large sub drivers are in the 96dB to 100dB region.

 

All I'm saying is that 123dB at 15m seems unlikely.  1.5m OTOH possible. I just think some numbers may have been mixed up.

Quite possibly, I seriously doubt I've hit those numbers quoted.

But 123dB I know ive done, but then I'd always wonder about thae accuracy of the SPL meter being used.

Anyhow as a guide its fine. I'm really not doing it for a pissing contest, it's just sometimes things happen 

 

 

33 minutes ago, playdough said:

Hi, it's possible, was a long time ago and second hand information.

Something about a sore ass from a non stop drive from Bathurst came up as well. 

 

We can maybe agree Joe has one of the loudest domestic HiFi's ever and loves to arc them up.

 

Oh the Bathurst trips,  at the time was my influence on building a system.

The Frankensystem, also active. A system that shouldn't work according to the purists. But one hell of a blast.

[davewantsmoore]

16 hours ago, playdough said:

A bloke mentioned to me once he visited Joe and the Illuminators, did a quick SPL measurement from some 15m away @ 123dB, said it sounded a little thin in the sub 80 Hz department

So a frequency response problem, then.

 

The only way to fix a frequency response problem is with EQ, or by moving the listener, or by moving the woofer(s).... or by adding (akin to moving) more woofers in different locations.

 

16 hours ago, playdough said:

How can doubling the bass woofer count be in any way "not a drawcard" of coarse it would be, seriously. Give me your reasoning,

It will fix the problem of insufficient SPL vs distortion.

Sounding thin is not a symptom of insufficient SPL vs distortion.   8x high excursion woofers should be fine @ 123dB.

 

16 hours ago, playdough said:

2 x 18" long throw drivers, in a single sealed 200 litre cab,,,,,,,,,,,another cab to make a stereo pair,,,,,,,,,physics again Dave.

Yes, (assuming in a room) because the new cabinet is in another location (which solves problems of linear distortion)   As you said, physics.

 

(Non linear) distortion, when below sensible values is inaudible.

 

16 hours ago, playdough said:

What do you do at an ACDC Concert run a pair of subs or 30 subs. What would the Crowd recon of 2 subs, not a lot.

It all depends on the SPL requirement.

 

If Joz already has enough SPL vs distortion (which I bet he does, but) .... then there is no problem to solve.

OTOH, rooms always have linear distortion problems, without bass sources in many locations.

 

[davewantsmoore]

16 hours ago, joz said:

I know I’ve had it up there but even I’m not sure at 15m?

LOL, I didn't even both addressing that one.

[davewantsmoore]

5 hours ago, March Audio said:

What's the sensitivity of these speakers? Would be interesting to calculate how much power is required to hit 146dB.

At a real basic calc.  8x 12" @ 20Hz is 33mm for 123dB (1m).   The drivers are quoted as able to move 40mm.

Power will depend a lot on the cabinet.

 

4 hours ago, playdough said:

We can maybe agree Joe has one of the loudest domestic HiFi's ever and loves to arc them up.

I'd be more concerned about the tweeter, than anything, if looking at stupendous SPL.   It could in theory (~1mm movement @ 4khz) make >> 120dB... but the power input can easily get unrealistic.

 

[GregWormald]

On 02/11/2023 at 8:18 AM, cheekyboy said:

 

<snips>So, to stay on topic, the SGR Illuminators and the SGR MT3.2 which have also got a mention in this thread, are the very best loudspeakers I've had the pleasure to listen to, bar none....... and they are both fully sealed/non ported enclosures.

 

Cheers,

 

Keith

My current amps/speakers are the latest iteration of the SGR MT3 series, the MT3.3, where Stuart said the re-design enabled better bass and more efficiency as well. They're well worth a listen.

...........

Anyway, relating the speakers to music "as the artist intended" illustrates issues.

The hearing and preferences of the artists, the venue in which they are listening, the amps and speakers to which they are listening all have an effect on the final mix.

 

I have some albums where the bass has to raised to even hear it, and some where it has to be lowered otherwise it overcomes the rest of the music. I'd rather change the speakers' response rather than my pre, amp, speakers, room, preferences, and inbuilt hearing for each album.

 

 

 

Edited November 4, 2023 by GregWormald
added more

[cheekyboy]

13 hours ago, GregWormald said:

My current amps/speakers are the latest iteration of the SGR MT3 series, the MT3.3, where Stuart said the re-design enabled better bass and more efficiency as well. They're well worth a listen.

 

 

Hello Greg,

 

You indeed have an outstanding pair of loudspeakers in the MTs and because I’m living back in NSW now, I sadly don’t have the pleasure of listening to the SGR loudspeakers as much as I did when I was living down in Melbourne.

 

I was back in Melbourne in April this year though to deliver a pair of loudspeakers and I took the opportunity to visit SGR while I was down there and had a session with the MTs and a superb Brinkmann Balance turntable as the source.* This is always a memorable session and something anyone who has a real passion for true high fidelity, should experience at least once.

 

Cheers,

 

Keith

 

* Brinkmann Balance turntable/Acoustical Systems Axiom tonearm/Acoustical Systems Palladium cartridge/Brinkmann Edison MK II phono preamp.

 

 

Edited November 4, 2023 by cheekyboy

[murrmax]

Quote

Anyway, relating the speakers to music "as the artist intended" illustrates issues.

The hearing and preferences of the artists, the venue in which they are listening, the amps and speakers to which they are listening all have an effect on the final mix.

 

Issue is the mixing process involves compressors and filters used to limit dynamic range and mixed on small ported speakers to ensure the mixes sound good for the majority  - once you have a reference level system this becomes problematic as you mention some tracks sounds like they have no bass, but it's just that they've compressed it out so as 'as the artist intended' is a dubious claim, so it probably depends on the system that the engineers use to mix, i.e is it a 2 way 6.5 in midbass + tweeter or something with 18inch bass bins, 10in midrange etc  guarantee the mix will be different eitherway and will have an outcome on what you describe as i have had similar experiences - you need to adjust the response in the bass for each album pretty much. Plenty of engineers detest the fact that they have to appeal/mix to the lowest common denominator but what can you do.. imagine all those 6.5in consumer drivers spitting the dummy from the dynamic bass..

[joz]

On 3/11/2023 at 8:16 PM, playdough said:

A bloke mentioned to me once he visited Joe and the Illuminators, did a quick SPL measurement from some 15m away @ 123dB, said it sounded a little thin in the sub 80 Hz department, but good.

Interesting, the one I’ve I’ve never thought I’d was a little thin. But who knows what was playing or if the sub amps went into protection? Or just personal taste?
The one thing that I have done is have anything above 80hz a little recessed only because it suits my listening tastes having the mid bass a touch cooler cooler, then the mids a bit cooler again. From there running flattish through to the tweeter.

 

Oh, the tweeter is rated 4 ohm 90dB sensitivity,130 watts long term max power. I’ll let you guys work out how many dB a pair will give me

 

BTW, you guys are always welcome for a visit. I know the rig/ room isn’t perfect but certainly is fun  

 

Edited November 4, 2023 by joz

[dcathro]

I also wanted to post multiple answers to the poll!

 

I have both sealed an ported speakers.

 

There are advantages and disadvantages to both, and it really comes down to the driver choice and what you are trying o achieve with the speaker.

 

My sealed speakers use a 10" long throw acoustic suspension woofer, in a 70L enclosure, that goes down to low 20s Hz, but they are a 4ohms load and only 87db sensitivity (equivalent to 83db @ 8ohms). This means they need a very powerful solid state amp. They have phenomenal bass for their size, but will not play very loud.

 

My ported speakers use a 15" underhung woofer, in a 130L enclosure, that goes down to 30 Hz. These are a much easier 8ohms 94db sensitivity load allowing a wider range of amplifier usage. The low bass is not as impactful in these as my smaller sealed speakers, but they can go way louder with no issues.

 

 

[Bass13]

Just finishing reading this thread again, I now have ported & Unported speakers, what I'm hearing from my system so far.

 

This is my first pair of Unported speakers which have been placed into the same spot my ported ones where in, the difference is Bass seems faster, tighter and I don't hear that air sound "down firing port" on a big bass note at higher volume's, but I also noticed it takes more Amp juice to produce too.

 

I'm still getting my head around this, as these are brand new speakers so they do need time to break in so to speak, the woofers need some work during this time to loosen up to their ideal compliance, the crossovers contain a lot of large, boutique components with plenty of teflon and other dielectrics to condition.

 

Dare say within the next couple of months will give me a better idea when things settle in a bit, but at this stage, I still like both Ported & Unported speakers.

 

Edited March 26, 2024 by Bass13