REL Quake or ACI Force for semi small room



Rega Planet, P3, Mira (old clamshell style)
Ruark Prelude R's (gorgeous speaker and midrange)
QED Silver Ann / Quect 3's

Looking for a musical sub to fill out bottom end in a semi-small room with hardwoods. Owned a Strata III and Rega Vulcan and loved both. I'm torn between REL Quake (smaller, british synergy, 23hz-6db) and ACI Force (return policy, more air movement from 10in driver, 20hz-3bd). Both are around $750.

Any suggestions? I know, both will work beautifully but maybe someone has some other insight.

Thanks,
Matthew
Seattle

britergy
Neither, Velodyne DD10. But if you must have one of those, the ACI definitley.

Is it raining?
I agree; I love RELs and ACIs are good too, but the room correction of the Velodyne DDs is too good to pass.
Thanks, the DD technology sounds interesting but I'm priced out.

Anybody heard an Essex SW-1? Essex is the OEM from REL, Ruark, and Rega subs. www.essex-audio.co.uk

Matthew
It was my understanding that the rega vulcan is made by REL. Is it another sub you're referring to ?

I'm wondering why you don't want another strata 3 ?
I'd love to get a Strata again. The problem is that they are no longer imported to the US. Why, I have no clue. My local dealer says that the Q150e is more popular. Yeah right, the Strata III is universally reconized as a fabulous piece. Not the most impactful sub in terms of moving air, but tight and oh so musical. So, myself and lots of other 2-channelers will be wrestling over the few Strata III's that people sell used. I can't believe I sold mine initially. Stupid move.

Anyway I am referring to an Essex SW-1 (www.essex-audio.co.uk). This sub is a bit smaller (12 x 12 x15) than a Strata and uses a 120W amp. Essex builds the REL subs (and Ruark, Rega too). So supposedly, they're cutting out the middleman and selling direct trough a US importer. The SW-1 sells for around 1K and goes down to 18hz. It all looks good, I just haven't been able to find another enthusist who's heard one. I'm not going to drop the $, without a second opinion to the dealer.

So, anybody heard an Essex SW-1 out there?

Matthew
At what frequency did you have the strata crossed ?

I currently have my strata 3 set at 46Hz, but with my pervious speakers it was crossed at 28Hz. I notice that the Essex-audio sw-1 only crosses as low as 40Hz. That would not allow it to be partnered with anything more than a modest size standmount speaker, and almost certainly not with any floorstander.

It seems that the new RELS are very overpriced in the US, so the Velodyne DD series might represent a better buy here.
your right, that is a concern of mine. i can't remember where i had the Strata crossed. my Ruark floorstanders go down to 48hz so it will be cutting it close. i'll email essex and ask them why the 40hz. i noticed their super sub the SW-3 also crosses only down to 40? weird, maybe they have an explaination or the website is incorrect.

matthew
48Hz floorstanders with a 40Hz sub cutoff is indeed quite close. Close enough that I'd want a home demo before committing my money.

I'd hold out for a used REL. I bought mine used several years ago and they still sell for what I paid (about $800), so it's a bit like money in the bank (particularly with current interest rates !).

The velodyne DD series do seem to be almost universally thought to be better than the REL strata, but they are much more expensive .... I guess you pay your money and take your choice.
Agreed, I should wait for a Strata III. I'm crossing my fingers...

Below, I've copied the Essex response. If I remember correctly it is better to cut the sub off lower than let the mains than to have them playing the same notes. This would product a bloated sound in that range. Any thoughts here?

So being able to cut the sub off lower than 40 seems important.

Essex response:

We have found from experience that the having the crossover at 40Hz has not limited the use on all but the best floorstanders, this is partly due to the fact that although the specs on the floor standers may say they go to 35Hz this is normally a -6dB point or even a -10dB point. That said when setting the sub up you would need to set the crossover slightly higher than the lower notes on the main speakers. The lower limit of the SW1 is about 25Hz.

There is a limiter on the SW1 and I would say that it possibly very similar to the REL, out of interest we produced the REL models up untill about 3 years ago.

Regards


Tom Pearce
__________________________________________________
B.K. Electronics, Unit 1, Comet Way, Southend-on-Sea. Essex
Tel:- 01702 527572 Fax:- 01702 42024
Dear Matthew and friends: My advise is that you need two subs in your, btw in any audio system.

Please take a look: http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1117893153&openflup&27&4#27

The crossover point is extremely critical and my experience always told me that it has to be at around: 80Hz.

Regards and enjoy the music.

Raul.
"That said when setting the sub up you would need to set the crossover slightly higher than the lower notes on the main speakers"

That has not been my experience at all. I have always had to set about 5 Hz lower than the stated -3dB point of my speakers.

Raul ... 2 subs MAY load a room better than one, but they also cost twice as much. Given a budget of $1000 I'd rather pick one $1000 sub than two $500 subs.

As for crossover ALWAYS being at 80Hz that would only apply if you are filtering the signal to the main speakers. If you are running the main speakers full range then the sub crossover frequency will depend on the specification of the main speaker. No one frequency will work.
yes, the guys at ACI recommend using a 60 or 80hz passive high pass filter on the mains. this just plugs inline to the interconnects b/t the pre-amp and amp.

i am curious if anyone has done this?

it certainly makes sense to not drive the speakers as hard in the lower realms.

at the same time, the thought of putting a cheap capacitor into my system seems like an added complication. because i have an intergrated, i'd have an interconnect leaving the pre-amp outputs, looping out, through the crossover, and right back into the amp input = weird.

my local dealer says that the high pass addition is silly, that the speakers roll off naturally where they should. the sub should just augment this natural roll off.

hum?
Dear Sean: It is not only that two subs may load a room better than one, it is that two are necesary for the stereo effect remember that the music is not only " fundamental frecuencies " but harmonics too.

Btw, I'm not saying that the crossover be ALWAYS at 80Hz but this is a good point to start when you are filtering the signal to the main speakers. I agree with you that no one frecuency will work.

+++++ " That has not been my experience at all. I have always had to set about 5 Hz lower than the stated -3dB point of my speakers. " +++++

I respect your point of view but I'm not agree with it on this regards: we have to remember that we use subwoofers not only for a better quality/quantity low bass but for a better mid bass/mid range performance.

Regards and enjoy the music.
Raul.
Dear Mattehw: With all respect your dealer dos not know nothing about, sorry.

+++++ " it certainly makes sense to not drive the speakers as hard in the lower realms..." +++++

Certainly is. Please read carefully the link that I already give you ( the one that I post in this thread ). Read from SUDDENLY and below. It will be interesting for you.

Regards and enjoy the music.
Raul.
Raul
Rel subs do not filter main speaker outputs.They are not like other subs and you cant think of them as such.When you set them at say 35 this not a typical crossover. The rel will rolloff below AND ABOVE this point.The proper setting depends upon the slope of the rolloff of both the speakers and the sub.For example: I dont recall exactly but I think the slope of rels rolloff(up) is 6db per octave which means a sub set at 20 will be -6db at @40hz (the octave is 20-40 at this frequency).This would integrate perfectly with speakers that were flat at 40 and -6db @20hz assuming the output is set properly.This is why rels are typically "crossed over"at such low frequencies. Obviously perfect integration is difficult to obtain but approaching it requires knowledge of the slopes of both speaker and sub frequency rolloffs(up). You could just "trust your ears" but this assumes you are used to flat response and not the more common midbase bump most are.
Jim
Dear Jim: Tks, now I can understand about.

Regards and enjoy the music.
Raul.
Dear Matthew: The Rel subs are a very good ones but are inadequate for a proper stereo music/soun reproduction.

I think that the REL design is more adequate to HT applications than for a stereo music reproduction.

For a less distortion design the REL subs sum-up the left and right channel signals and always works in mono way, this single characteristic unfit for stereo aplications.

Again, please read carefully at: http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1117893153&openflup&27&4#27

Regards and enjoy the music.
Raul.
Raul ... the problem with your answers is that you always assume unlimited (or very high) budget.

All hifi components may be "inadequate" but also may represent the best compromise at their price points. The art of engineering is to find the best balance of compromises in order to hit the market at the correct price point.

If a REL (or similar) is inadequate I think you should tell us how you propose to improve on the REL for a budget of $800, roughly the cost of a used Strata 3.
Dear Sean: " unlimited budget ": all my post always are thinking in benefits/improvements for the proper stereo music reproduction, but you are right about the " budget " I almost not think about, sorry for that.

You are right too about " the best compromise at their price points ". But this is not the issue, the issue still is: PROPER STEREO MUSIC REPRODUCTION AT HOME.
There is almost none situation where the REL subs can meet this statement. The REL subs has a design that's is better for HT applications.

+++++ " I think you should tell us how you propose to improve on the REL for a budget.. " +++++

There are other subs alternatives to REL for proper stereo reproduction: Velodyne, Paradigm, M&K, HSU, Bag End, B&W, etc....

Regards and enjoy the music.
Raul.
Perhaps you could be a little more specific. Say for example:

I have $800 to spend.
I have an integrated amplifier.
I like the sound of my monitor speakers, I just want to extend their performance.

Sure, there are other sub manufacturers, but you have given no indication of how their offerings could give a superior solution at the given price point.

If someone were to ask how to get better performance from their honda civic and they have $1000 to spend telling them to go trade for a 911 turbo doesn't really help them.
Dear Sean: Others subs manufacturers give you the option to integrate their subs in a truly stereo fashion not like the REL ones that always give you a mono signal sound reproduction.

Like Eldartford post on the subs analog forum thread:
+++++ "I regard the "subwoofer" not as a separate speaker system, but as part of the main speaker system...the part that the manufacturer left out because of size and cost. " +++++

We need two subs for a proper stereo music sound reproduction not only one. Sure you can use only one but that can't say it is right. Maybe some people use only one sub and in this unortodox application the REL is fine, but I repeat: FOR A PROPER STEREO MUSIC REPRODUCTION AT HOME WE ALMOST ALWAYS NEED TWO SUBWOOFERS.

Please take your time and read carefully the link that I already post elsewhere in this thread. There you can read all the advantages, other than " more bass ", that we can have when we integrate subs in our stereo audio systems.

Regards and enjoy the music.
Raul.
Raul, RELs only sum to mono if you connect both channels of the power amp. You can connect two REL subs, one to the left channel and one to the right channel if you desire. You then have true stereo sub bass.

RELs can be connected to the power amp or to RCA or balanced outputs from a preamp or processor also. With either method they can run true stereo or mono-mixing.

Besides, with a sub upper rolloff at 35Hz how much LP information is in stereo at that frequency. It is my understanding that bass is summed to mono on most LPs. Strange then that most audiophiles profess to preferring LPs.

In general I agree with you that two subs will provide a better room loading, that 80Hz may be a good integration point, and that integration as high as 80Hz may cause the sub to be more directional than in my case (crossed at 45Hz).

But I contend that you cannot do what you are suggesting with a budget of $1000 or less.
Dear Sean: My mistake is that I read the operation manual where they speak about the speakon connector and I never " seen " the stereo application. Sorry for that.

Mi issue is to leave free of low bass reproduction the woofer in the main speakers, in this way we can eliminated almost the most severe intermodulation distortion and heavy harmonic distortion that do a great degradation to the music reproduction.
In this way we can have many advantages: better quality/quantity low bass, clean mid bass, clean midrange/high frecuencies, etc....

Now, the start crossover point at 80Hz works very well and I can tell you that at this crossover point you can't detect the stereo subs.

About to summed the bass: remember that the bass is not only fundamental frecuencies but a lot of harmonics that we have to " hear " in stereo.

Tks for your time.

Regards and enjoy the music.
Raul.
Hi Raul,

"Mi issue is to leave free of low bass reproduction the woofer in the main speakers, in this way we can eliminated almost the most severe intermodulation distortion and heavy harmonic distortion that do a great degradation to the music reproduction"

I can see definite advantages in relieving the main speakers of their lower bass. I am in complete agreement in this respect.

However I also see a disadvantage: The higher the frequency at which the subwoofer is crossed the more directional the subwoofer becomes, and the more difficult it is to place the subwoofer for even room loading.

Your solution of two subwoofers solves this disadvantage, but it also approximately doubles the cost.

So I think that your solution of crossing at 80Hz and using stereo subs is probably optimum, but I doubt it can be achieved for under $1000.

By crossing at a very low frequency (20-40Hz) the REL is much less directional, and loads the room a bit more evenly and so it allows a single sub to be used to good effect.

The negative aspect of this approach is that it does nothing to ease the stress on the main speakers, so no midrange clarity is gained.

Horses for courses !
Dear Sean: You are right: it can't be achieved for under 1K. But the advantages of use of two subwoofers in an audio system is worthwhile the " financial " effort.

+++++ " The higher the frequency at which the subwoofer is crossed the more directional the subwoofer becomes.. " +++++

The issue here is to find the right crossover frecuency point in our room/system. When you find it you will be in " music heaven ".

I work very hard on this issue before my subs disappears. I find that this happen at around 80Hz. I corroborate this in other friend's systems . That's why I always speak " around 80Hz ".

Regards and enjoy the music.
Raul.