upgrading Dunlavy SC-IV

[jkbtn]

Has anyone done it? Especially improving base extension??
Huge speakers but disappointing base performance. I just want to do something about this.
I'm thinking of replacing the stock 10" Vifa woofers by the Seas 10" aluminum woofers.
Thanks for the info.
jk

[Pat D]

Has anyone done it? Especially improving base extension??
Huge speakers but disappointing base performance. I just want to do something about this.
I'm thinking of replacing the stock 10" Vifa woofers by the Seas 10" aluminum woofers.
Thanks for the info.
jk
They seem to be relatively sensitive speakers with usable bass extension to about 30 Hz. Check the measurements in Stereophile.

http://www.stereophile.com/loudspeakerreviews/166/index5.html

I doubt tinkering with the drivers in such a well-engineered speaker would accomplish your goal. Why don't you get yourself a good subwoofer? One of the top models from Hsu, SVS, Paradigm, Velodyne, and so on?

[RGA]

Has anyone done it? Especially improving base extension??
Huge speakers but disappointing base performance. I just want to do something about this.
I'm thinking of replacing the stock 10" Vifa woofers by the Seas 10" aluminum woofers.
Thanks for the info.
jk

I would not tinker with a speaker unless the designer has some approved tweak - you may not know what adverse effect will result by changing drivers. Presuably Dunlavey chose the specific driver for a reason.

Another example of measurments not yielding real world results because 30 hz should shake your house and crack plaster. Unless they can't play loud while also producing bass.

Adding a sub works - presuming any of them actually go under 30hz - or is it the local $700.00 Velodynes that just plays 40Hz real loud? Useless. Good for home theater though presumably.

Is your amp and cd player etc working properly and wiring sufficient? Most rock does not contain a lot of deep bass. Try and get some known bass heavy discs to be sure. But not JUST bass heavy tracks...you want something with a femal voal in there at the same time to see if the voice is in ANY way sludged while the speaker is ALSO producing deep bass. Diana Krall's latest album "The Girl in the Other Room" has impressive bass a vocal and piano - Sound and Vision didn't like the disc's recording but they need better speakers. Also the last track(though others are capable) on Sarah McLachlan's Mirrorball live album or "silence" on her remix album should offer a tremedous amount of scale and deep piano. The remix album is synthesizer heavy but the synthesizer is full range.

Normally I would suggest a big Organ but you need busy passages to ensure it's not just able to one thing and not the other simultaneously.

Try and move the speakers closer to a rear wall. I can't remember the Dunlavey's because they're no longer around but bass is largely a factor of positioning. I play the same music on repeat and then get a quick sense on how the bass is performing against room boundries and if there are clearly audible problems. Positioning for most speakers range from absolutely critical to relatively easy going - but even the latter can be picky to get just right. That is why the manuals usually have pretty large positioning instructions - mine for example say 30cm to 1 meter from a rear wall - like to be in corners but not mandatory - height 14-16 inches(standmounts) - then you have them say no toe in to a ridiculous toe in 2 meters in front of the listener depending on the room and of course the listener's preferences. And heck then you also have the distance apart to consider.

Your speakers should be presenting considerable bass - my Wharfedales rated at 40hz can produce considerable depth(and go below this rating) and would probably satisfy most even bass hounds. I had the best Boston Acoustics Subwoofer years ago which I sold because it added nothing to the bass response and certainly I would not want to use the cut the Wharfedales' off and let the Sub handle the bass - that was a disaster for stereo and didn't go as low - despite the lower frequency rating of the sub.

Try the positioning - if you're not satisfied consider moving to a different speaker - Dunlavey may have large support and you might get a good amount selling them. Indeed, selling them sooner than later might not be too bad if in the future something goes on them you might not be able to get original Dunlavey parts

[jkbtn]

Thanks for all that advice.

[Romy the Cat]

Dunlavy SC-IV were quite dreadful model as there was no good 10-inshers. This is why John went for IVA model replacing the woofers with Scan Speak 25W/8565-00 drivers with Fs=20Hz.

The Pussy

[jkbtn]

Just want to let you know that the streophile review (that you quote) was about the SC-IVa, not the original SC-IV that I have. There is huge difference in bass performance between the two models, despite using the same cabinet.

SC-IV : 37 hz - 20 khz
SC-IVa: 20 hz - 20khz

[Romy the Cat]

Just want to let you know that the streophile review (that you quote) was about the SC-IVa, not the original SC-IV that I have. There is huge difference in bass performance between the two models, despite using the same cabinet.

SC-IV : 37 hz - 20 khz
SC-IVa: 20 hz - 20khz

jkbtn,

Apparently you have no idea whit who you deal with. I do not quote any “reviews”. The idiots who write those audio doodles in their funny audio publications quote me, not wise versa. The SC-IV used the woofers with free air resonance at I believe ~30Hs or something like this, with soft resonant rubber suspension and quite mean bass altogether. (They tried to add the cone mass but it sounded like crap, although the brainless reviewers I am sure have written their hundreds of the drooling pages) With the SC-IVA they went to the drivers that I mentioned, and those drives where way more interesting, although they still had some “issues” at upper bass, but it will be way beyond you to mention those “issues” (considering that you still think in terms of the aluminum drivers). Actually those drivers (25W), altogether were even more interesting than the drivers they used even in SC-V and VI models. (Dunlavy always used the chipset and the crispiest driver possible) It is doable to replace the woofers with 25W/8565-00 (~$110/each) and to trash the foolish Dunlavy’s impedance comparator in the LF but it would requite some skills.

If you not satisfy with my answer then talk with some kind of Suzy The Rochlin reviewing "intelligence" and those Morons would suggest you how to sprinkle the speakers with coca-cola to enrich the "sweetness of the presentation" or how to position the tower on 3 bottles of Budweiser in order to get the famous “Bud” bass....

Sorry, I did not read any reviews about the SC; perhaps I missed something in my life….

Good luck in your journey...
The caT

[RGA]

Whoah Romy

Give the guy a break - he just wants to know if he can get more bass by changing the driver.

If you have a way to get his speaker to sound better then let him know - if you think he should buy a different speaker that's fine too - but you don't need to bash him.

Martin Colloms reviews products and he is one of the world's formost experts on both audio engineering, speaker design and psychoacoustics and has the impressive papers to back it up. Rochlin is a passionate reviewer who listens to products - he doesn't claim to be an engineer. Based on a listening sessions I would not trust either of them - you have to listen for yourself.

[Romy the Cat]

RGA,

I would suggest t you to deal with the reality if my answer but not with your personal fear of what I might “meant to say”. Your perception that I “bash” the guy is way off and that perception follows a common pattern of a self-intimidation. Please relax, and do not consider yourself in obligations to “save the world”, and particularly the pathetic world where a messiah comes in the shape of a brown truck.

Te Cat

[Pat D]

Just want to let you know that the streophile review (that you quote) was about the SC-IVa, not the original SC-IV that I have. There is huge difference in bass performance between the two models, despite using the same cabinet.

SC-IV : 37 hz - 20 khz
SC-IVa: 20 hz - 20khz
Sorry, I haven't kept up on the details of the different models. The usable bass in the SC-IVa would get down into the 20's based on John Atkinsons's measurements. Needs a subwoofer for full range performance.

Replacing the drivers would still leave you with 10" woofers. So my advice remains much the same: if the bass performance is not deep enough for you, get a big subwoofer that goes below 16 Hz.