SGR Audio Owners & Discussion Thread

[anthonyc]

Or just email Stuart and ask him for the prices :-

sales@sgraudio.com

[SGR Audio]

Intriguing. What type of design is it - ported or sealed? Also, how many dB down is it at 16Hz?

Best regards, Cameron.[/b]

Hi Cameron,

It's a sealed box. In JohnA's room it was flat to 13Hz, at 16Hz it's not down at all. The thing is though with such low distortion, you can not 'hear' it much below 25Hz, but the doors/seats rattle and there's a whole lotta shakin' going on!

-Stuart.

[Phil G]

Hi Cameron,

It's a sealed box. In JohnA's room it was flat to 13Hz, at 16Hz it's not down at all. The thing is though with such low distortion, you can not 'hear' it much below 25Hz, but the doors/seats rattle and there's a whole lotta shakin' going on!

-Stuart.[/b]

Hi Stuart

I assume that unless we have a pretty huge room, we are not going to hear much below 25Hz anyway (due to the wave-length), but it sure is nice to feel it

I hope to hear these subs one day.

[SGR Audio]

Hi Stuart

I assume that unless we have a pretty huge room, we are not going to hear much below 25Hz anyway (due to the wave-length), but it sure is nice to feel it

I hope to hear these subs one day.[/b]

Hi LD,

You dont need a huge room to reproduce subsonics. This is a bit of a myth. Sound at any frequency can be created in any size room. A decent pair of headphones will reproduce 25Hz :wink:

In a listening room, frequencies below the first standing wave are reproduced in what is called pressure mode and the response rises with decreasing frequency (known as room gain). Above this frequency, standing waves are present and should be well distributed and well damped.

Your room operates in pressure mode from about 50 to 60 hz and below and you will have a large room gain in the subsonic region. Dont stress though, it can be fixed (equalised) but it takes specialised measuring equipment and circuitry to get it right.

Cheers,

Stuart.

[Mr_Gimlet]

Update #1

OK, so I've had it for a few days now. I've also noticed a rather cool blue light on the back of it. The cat tried to jump on it and promptly skated off.

Additional demo tracks:

Praetorius: "Lutheran Mass for Christmas Morning"

Leonard Cohen, "I'm your man"

Vaughan Williams, "Lord, thou hast been our refuge", "Five Mystical Songs"

Bach, Cantatas for Reformation Sunday (19, 192 and 80)

Ben Harper, "Live from Mars"

Shamen, "Boss Drum"

The Orb, "Orblivion"

Widor, "Mass for 2 choirs and two organs"

Leon and Eric Bibb, "Praising Peace"

All I can really say is that it plays the notes which I know are there. There is no obvious gap or overlap in the changing over from the mains to the sub, and the room appears to be tamed.

I'm cautious about getting too effusive, as I have never had a sub in this class/ price bracket, and I can't just do a comparison with it turned off. However, it is much better than my B&W ASW1000. Also, I'm probably concentrating on listening to the music which is a well-known demo trap.

I'd say the main improvement is in the handling of the sub 40 (maybe even 60)Hz stuff, and there is more of it than I had expected, even on more contemporary vocal stuff - I knew it was there on thundering organs but hadn't expected to see much on blues vocals for instance. It fills out the sound much more - some of this is probably just taking stress off the midrange drivers, but I had the crossover before to my old sub and the sound is definitely fuller.

I promised I would try and address how it would fit in a non-SGR system.

First, having a really good crossover helps - mine is digital in my processor. Otherwise you are going to be matching curves and their differentials in the hardware.

Second, the SGR team 'setup' is based around 'measured is best' so if you have a carefully crafted system in the sense of not having an acoustically flat response, you run the risk of undoing some of the things you like.

Third, the Velo subs at this price level are much more configurable in terms of room correction - as far as I can tell, the initial setup of the SGRs does tweak, but then it is pretty much unchangeable. If you want to tinker, then the Velo might be more suitable. It's not an issue for me as I will do room correction in my processor.

[norpus]

Update #1

OK, so I've had it for a few days now. I've also noticed a rather cool blue light on the back of it. The cat tried to jump on it and promptly skated off.

Additional demo tracks:

Praetorius: "Lutheran Mass for Christmas Morning"

Leonard Cohen, "I'm your man"

Vaughan Williams, "Lord, thou hast been our refuge", "Five Mystical Songs"

Bach, Cantatas for Reformation Sunday (19, 192 and 80)

Ben Harper, "Live from Mars"

Shamen, "Boss Drum"

The Orb, "Orblivion"

Widor, "Mass for 2 choirs and two organs"

Leon and Eric Bibb, "Praising Peace"

All I can really say is that it plays the notes which I know are there. There is no obvious gap or overlap in the changing over from the mains to the sub, and the room appears to be tamed.

I'm cautious about getting too effusive, as I have never had a sub in this class/ price bracket, and I can't just do a comparison with it turned off. However, it is much better than my B&W ASW1000. Also, I'm probably concentrating on listening to the music which is a well-known demo trap.

I'd say the main improvement is in the handling of the sub 40 (maybe even 60)Hz stuff, and there is more of it than I had expected, even on more contemporary vocal stuff - I knew it was there on thundering organs but hadn't expected to see much on blues vocals for instance. It fills out the sound much more - some of this is probably just taking stress off the midrange drivers, but I had the crossover before to my old sub and the sound is definitely fuller.[/b]

Hi Mr G - thanks for the good oil on your findings

As a previous owner of the same B&W ASw1000 sub ($1400) you had also, yes that one would not go much lower than 30Hz even with room gain - and would sound muddy in comparison. It would have been similar in size to the sgr from memory, but ported, non EQed, had a weakish amp and a lesser quality of build and finish.

Whilst I never heard a side/side comparo obviously, I know I could never be happy with that asw1000 SQ anymore and it would be hard to feel a good integration now.

Whereas with the SGR octagonal sub, I'm confident integration in most two channel systems with the amplification, EQ and capability of the sgr sub would be fairly easy in comparison. I now know what good subbass sounds like and the sgr 10" is very capable of it. The only flaw it has, is like the Velo DD10, it is not designed for big rooms that its bigger brothers are designed more for, nor would it be especially strong for HT unless in a small room - in fact it is true to its design brief as an easily integratable audiophile sub.

[norpus]

Also, how high can they go, as in frequency, not volume.[/b]

Funnily enough, that question has been answered - the drivers have been measured good to 500Hz - not bad for a true subwoofer! (lets see 16Hz - 500Hz flat is a full 5 octaves capability)

JohnA and I actually tried to test this at his place using his Rotel avr crossover maxed at 200Hz , crossed into the Octagons (with their twin 10" woofers) and compared that versus the previous 25Hz crossover setting ie use the sub for midbass as well as sub bass

And what did we find? Pretty good midbass was our conclusion and a lightening of the load on the Octagon drivers.

Then SGR pointed out later that the sub amp has a 125Hz low pass filter in circuit hahaha so we were missing a bunch of midbass input. Oops - ignorance is sometimes bliss. :blush:

[Keith_W]

Mr Gimlet (or someone?), can you please post in detail the setup process of this sub? Do sweep, twiddle gain controls, do sweep, twiddle some more? And would you mind posting a picture of the controls at the back of the sub? I am wondering whether the controls on this sub is enough or whether it would benefit from adding something like a Velodyne SMS-1 outboard controller.

[SGR Audio]

Mr Gimlet (or someone?), can you please post in detail the setup process of this sub? Do sweep, twiddle gain controls, do sweep, twiddle some more? And would you mind posting a picture of the controls at the back of the sub? I am wondering whether the controls on this sub is enough or whether it would benefit from adding something like a Velodyne SMS-1 outboard controller.[/b]

Hi Keith,

I've posted a pic of the amp a few times now, but here it is again for those who missed it...

The controls on the sub are enough to integrate into any system, so an SMS-1 is not needed. The only benefit of the SMS-1 might be the parametric EQ if you have harsh room modes that need controlling. Mr Gimlet does not have much of a room problem at the frequencies where the sub is operating. His mains have a slight boom at about 90Hz but I believe this will be taken care of when he gets his new processor.

-Stuart.

[Drizt]

Hi Stuart,

Just a quick question...

At Norpus' place I remember there was talk that RCA outs on the plate amps had a fixed crossover value of 80Hz, is this still the case or is it variable now?

[Keith_W]

Thanks for that, SGR. I am a little confused about the two crossover controls though - if one crossover was set to (say) 50Hz, and the second to 125Hz, then is the second (125Hz) doing very much? I realize that if you set both to the same frequency then you would double the x-over slope.

[SGR Audio]

Hi Stuart,

Just a quick question...

At Norpus' place I remember there was talk that RCA outs on the plate amps had a fixed crossover value of 80Hz, is this still the case or is it variable now?[/b]

Hi Drizt,

It's fixed. But I can make it any frequency you need...

However, I'm thinking of removing the high pass outputs on the next revision of this amp (refer to the thread a while back on crossover point vs natural rolloff for reasons). This brings up a good question :-

How many of you out there use your high pass on your sub amp to run your mains?

[SGR Audio]

Thanks for that, SGR. I am a little confused about the two crossover controls though - if one crossover was set to (say) 50Hz, and the second to 125Hz, then is the second (125Hz) doing very much? I realize that if you set both to the same frequency then you would double the x-over slope.[/b]

Yep, setting them at the same frequency would give you a 4th order slope. With the second set at 125Hz as in your example above it would not be doing very much so essentially you will have a 2nd order slope where you need it.

[Drizt]

Hi Drizt,

It's fixed. But I can make it any frequency you need...

However, I'm thinking of removing the high pass outputs on the next revision of this amp (refer to the thread a while back on crossover point vs natural rolloff for reasons). This brings up a good question :-

How many of you out there use your high pass on your sub amp to run your mains?[/b]

Just a quick question, is there a reason why it can't be variable also ?

[norpus]

Hi Drizt,

It's fixed. But I can make it any frequency you need...

However, I'm thinking of removing the high pass outputs on the next revision of this amp (refer to the thread a while back on crossover point vs natural rolloff for reasons). This brings up a good question :-

How many of you out there use your high pass on your sub amp to run your mains?[/b]

I haven't previously as wanted a lower crossover eg 60Hz was my preference for the B&W/IB combo

Now with getting the Octagons I won't have the same requirement as they go lower, but I can see it should be useful to some in 2ch setups who want to run a sub.

[SGR Audio]

Just a quick question, is there a reason why it can't be variable also ?[/b]

Electronically its easy to make variable, but unless you crossover an octave above your natural rolloff the sub wont integrate 100%. I'll think about this one and see what the best solution might be.

Still interested in how many high pass their mains? Anyone?

[Moondog]

Electronically its easy to make variable, but unless you crossover an octave above your natural rolloff the sub wont integrate 100%. I'll think about this one and see what the best solution might be.

Still interested in how many high pass their mains? Anyone?[/b]

Hi Stuart , My thoughts As a SE Triode user who would like to try some subs at some point .

Would like to use a high pass filter . To reduce the load on the main amps.

But I would rather have the filter fitted between the pre and the power amp

I am not fond of the idea of running a interconnect cable , pre to sub and then back to the main amps

Moondog

[terry j]

just so I understand, when we talk about 'high pass' the mains using these (this) amps, I assume that means we run , I dunno, from the pre to the sub amp, it does a x-over function and then runs everything above the x-over point back to the power amp?

If that's true, the next obvious question is how clean/transparent is the x-over in the amp? I'd imagine it just simply can't be as good as some of the electronics run in some of these systems, so is there some 'rule of thumb' that that dictates when the quality of the system outstrips the quality of the xover in the amp?

[Phil G]

just so I understand, when we talk about 'high pass' the mains using these (this) amps, I assume that means we run , I dunno, from the pre to the sub amp, it does a x-over function and then runs everything above the x-over point back to the power amp?

If that's true, the next obvious question is how clean/transparent is the x-over in the amp? I'd imagine it just simply can't be as good as some of the electronics run in some of these systems, so is there some 'rule of thumb' that that dictates when the quality of the system outstrips the quality of the xover in the amp?[/b]

That is my understanding of high pass Terry.

I tried this a few months back with my DD15 and the result was poor. I ran RCA outs from my pre, to the sub, then more RCA's to the power amp. I played around with xover points, but the sound was vastly inferior to my usual setup.

[jrisles]

That is my understanding of high pass Terry.

I tried this a few months back with my DD15 and the result was poor. I ran RCA outs from my pre, to the sub, then more RCA's to the power amp. I played around with xover points, but the sound was vastly inferior to my usual setup.[/b]

How does this work though if you don't have a pre? I only have integrated amps. I want to incorporate a sub into my 2ch system but i have been wondering how this is done? I suspect that i run speaker cables from the outputs of my integrated amp to the sub then use the high pass filter outputs to connect my main speakers?

A 2ch amp is a bit different from a surround amp in as far as that it doesn't have a dedicated subwoofer output. So unlike a multichannel amp i believe that i would no alternative other than to run the 2ch's into the sub and then connect my mains to the sub?

The questions this raises (which i believe is the same as what others in this thread have touched upon) is that if i already have a good quality amplified signal coming out of my (integrated) amp & i then have to run this signal into the subwoofer before being passed through to my mains how does the electronics of the sub affect the electronics of the signal coming from my integrated? Wouldn't i be changing the "signature" of the sound by doing it this way? This is one of the reasons why i am not (yet) doing it.

I should add that my Unison Research amp have two sets of outputs for each channel, which is a little different to most integrated amps. So theoretically i could run a sub in parallel to my mains without the need to run the signal via the sub first.

cheers

Jeff

[SGR Audio]

just so I understand, when we talk about 'high pass' the mains using these (this) amps, I assume that means we run , I dunno, from the pre to the sub amp, it does a x-over function and then runs everything above the x-over point back to the power amp?

If that's true, the next obvious question is how clean/transparent is the x-over in the amp? I'd imagine it just simply can't be as good as some of the electronics run in some of these systems, so is there some 'rule of thumb' that that dictates when the quality of the system outstrips the quality of the xover in the amp?[/b]

Yes Terry, that's what high pass means :wink:

Regarding the quality of the crossover, there's no reason why the electronics can't be as good as a dedicated crossover unit. For example, the components used in the high-pass filter on my plate amps are the same components that I use in my active crossover modules. When I look at some of the cheaper plate amps on the market I am horrified and can understand why the high-pass outputs dont have a good reputation. But I guess it all comes back to the old saying, you get what you pay for...

[SGR Audio]

How does this work though if you don't have a pre? I only have integrated amps. I want to incorporate a sub into my 2ch system but i have been wondering how this is done? I suspect that i run speaker cables from the outputs of my integrated amp to the sub then use the high pass filter outputs to connect my main speakers?

A 2ch amp is a bit different from a surround amp in as far as that it doesn't have a dedicated subwoofer output. So unlike a multichannel amp i believe that i would no alternative other than to run the 2ch's into the sub and then connect my mains to the sub?

The questions this raises (which i believe is the same as what others in this thread have touched upon) is that if i already have a good quality amplified signal coming out of my (integrated) amp & i then have to run this signal into the subwoofer before being passed through to my mains how does the electronics of the sub affect the electronics of the signal coming from my integrated? Wouldn't i be changing the "signature" of the sound by doing it this way? This is one of the reasons why i am not (yet) doing it.

I should add that my Unison Research amp have two sets of outputs for each channel, which is a little different to most integrated amps. So theoretically i could run a sub in parallel to my mains without the need to run the signal via the sub first.

cheers

Jeff[/b]

Hi Jeff,

Try to avoid running your high-level signals (speaker cables) from your amp to the sub and then branching off again to the speakers. Does your int amp have any low level outputs (RCA's or XLR's)?

-Stuart.

[terry j]

thanks for that Stuart

so if you were to put these below the octagons for example..

I'm assuming that on the octagons there is some method whereby you can high pass the bass on them, and then use the same xover point in the subs? I'm curious because per John A he seemed to imply that he only used the subs from 25 hz down, which (in my relative ignorance) did not make a lot of sense to me. Surely a sub serves at least two functions, it allows greater extension of the bass AND relieves the load on the mains, ie in this example you would cross higher than 25 hz which also then fits in with your earlier comment about crossing an octave higher than your bass extension which would then allow proper integration of the sub.

[SGR Audio]

thanks for that Stuart

so if you were to put these below the octagons for example..

I'm assuming that on the octagons there is some method whereby you can high pass the bass on them, and then use the same xover point in the subs? I'm curious because per John A he seemed to imply that he only used the subs from 25 hz down, which (in my relative ignorance) did not make a lot of sense to me. Surely a sub serves at least two functions, it allows greater extension of the bass AND relieves the load on the mains, ie in this example you would cross higher than 25 hz which also then fits in with your earlier comment about crossing an octave higher than your bass extension which would then allow proper integration of the sub.[/b]

A sub MAY serve two functions like you have mentioned but with the octagons it only serves one - extending the bass response. The octagons don't need the load 'lightened', the 4 x 10" drivers can handle just about anything you can throw at them - even bass mechanik hey Russ!

At JohnA's we could have crossed the subs over at say 60Hz, but IMHO doing so you would loose the 'finesse' of the octagon bass modules as by themselves they will go down to 20Hz. Keep in mind that a system that goes down that low without a sub should always sound better than one that is crossed over to a sub (all else being equal, distortion, etc). As soon as you introduce a crossover into the chain you have made some sort of compromise (I won't get into the technical side of it but this is the reason I always try to keep crossovers out of the voice band 300Hz - 3KHz). Although, in saying that, if you can integrate the sub properly our ears are not all that sensative to problems down low and you can't tell the difference anyway. At JohnA's we did some tests and moved the crossover up to 80Hz - no one in the room could tell the difference. I would say that the benefits of highpassing a struggling set of mains and tuning in a high quality sub would far outweigh the crossover compromises though. :biggrin:

[norpus]

I would say that the benefits of highpassing a struggling set of mains and tuning in a high quality sub would far outweigh the crossover compromises though. :biggrin:[/b]

Hehe mine used to 'struggle' and sounded better to me with a crossover (and PEQ) to the IB sub at 60Hz. They were cheaper speakers admittedly than the ones I have coming :wink: