RBR-KIT, the “Recession Buster Reference” Kit, Pair

[---k---]

http://www.madisound.com/catalog/product_info.php?cPath=35_38_436&products_id=8644

Zaph isn't the only one that has been busy! Way to go Jed. :T


(And thanks for the heads up Zaph. It took me a little hunting to find)

[Face]

Nice choice of drivers and components. Clarity's new ESA's are a great bang for the buck.

[Jed]

Great timing . . . I leave for vacation on Saturday to visit my sisters. I'll still have access to internet though. I'm sprucing up my website as fast as I can.

On top of that it's been speaker building testing non stop for the last few months. This little kit rocks though so it'll be worth the effort. I think you guys will like it quite a bit! There's ~100 of them so get em while they're hot!

[Jed]

Way to go Jed. :T

Thanks Ryan! :T

[Hdale85]

I sent an email to Jed praising the amazing value of that kit. That will be a real treat for the very modest price!

[fjhuerta]

$400... great price point...

[augerpro]

Right on Jed! $400 is a bargain...

[HareBrained]

A pair of SS 15S drivers is ~$436 alone. As a kit you get two SB29 tweeters, crossovers and $37 for the purchase. That's an incredible value. And I imagine they must sound fantastic. I just wish I had the moola.

[NyxOne]

Upgraded crossover worthwhile

Great timing . . . I leave for vacation on Saturday to visit my sisters. I'll still have access to internet though. I'm sprucing up my website as fast as I can.

On top of that it's been speaker building testing non stop for the last few months. This little kit rocks though so it'll be worth the effort. I think you guys will like it quite a bit! There's ~100 of them so get em while they're hot!

Hi Jed,

Is the upgraded crossover worthwhile ?

I'm really considering a kit... or two! This is deal is too good to let it pass. :E

My wife don't it yet, but she's going to be mad, real mad at me when she'll see my new toys!!!

Chuck

[Hank]

:T Nice Jed, very nice

[NyxOne]

Hi Jed,

Is the upgraded crossover worthwhile ?

I'm really considering a kit... or two! This is deal is too good to let it pass. :E

My wife don't it yet, but she's going to be mad, real mad at me when she'll see my new toys!!!

Chuck

I just couldn't wait... I've pulled the trigger on one kit (with the upgraded crossover parts). When I told my wife that I planned to buy two kits she tried to unscrew my head, both hands around the neck (choking and shaking me)! So I guess one kit will do!

I don't know how "Madisound" can offer a kit of this kind at such a price but this is one hell of deal!

Thanks Jed & Mad!
Chuck

ThomasW : Please let me know if I'm stretching to much the forum's rules!

[soundemon]

If I wasn't still paying for my statement build, I'd pick up a set of these to try - looks excellent!

[Hdale85]

A pair of SS 15S drivers is ~$436 alone. As a kit you get two SB29 tweeters, crossovers and $37 for the purchase. That's an incredible value. And I imagine they must sound fantastic. I just wish I had the moola.

Yes I wish I had the money right now as well. Would be a fantastic speaker for my bedroom I think.

[Jed]

I just couldn't wait... I've pulled the trigger on one kit (with the upgraded crossover parts).

The upgraded crossover uses a lower DCR series coil that helps flatten the response a tiny bit. I like all the Clarity Caps... although I haven't used the uber expensive ones.

[NyxOne]

The upgraded crossover uses a lower DCR series coil that helps flatten the response a tiny bit. I like all the Clarity Caps... although I haven't used the uber expensive ones.

Well I've thought that considering the woofer quality I had no other choice to buy the upgraded parts otherwise I think they would have been upset!

Seriously this is the first time I'm buying a kit and I thought that 50 buck would not kill me. Also, I won't be asking myself what kind of sound they would have had with the upgraded crossover... I'll just know!

Chuck

[Jed]

Also, I won't be asking myself what kind of sound they would have had with the upgraded crossover... I'll just know!

Chuck

I'll look forward to your impressions when they are all done. Enjoy!

[wigginjs]

Kit is really an unequaled value. It makes you stop and just think "Do I have any justification, at all, to buy these, because they are a fantastic deal". Although, I think not having the option to use a pre-built cabinet (7.5" baffle width requirement) is limiting for kit builders. Thoughts on cabinet options?

[Hdale85]

http://www.madisound.com/catalog/pro...oducts_id=8252 well its close...lol

[Jed]

Kit is really an unequaled value. It makes you stop and just think "Do I have any justification, at all, to buy these, because they are a fantastic deal". Although, I think not having the option to use a pre-built cabinet (7.5" baffle width requirement) is limiting for kit builders. Thoughts on cabinet options?

They specifically didn't want me to use a certain competitor's cabinets for obvious reasons and the narrow baffle minimizes diffraction. Plus my cabinet calls for more bracing than you'll get with one of the prefabs.

I'm sure if you email some of the known cabinet builders around they should be able to quote you and get a good deal.

[---k---]

Jed,
Maybe I missed it, but your page isn't totally clear on the diameter of the port.

[ThomasW]

2" diameter double flared port with a total length of 9"

[fjhuerta]

Yes I wish I had the money right now as well.

Don't we all. As it is, I'm wondering if I can spare around $150 for my car's speakers... I hope there are enough kits so that I can get one in the future.

[HareBrained]

I noticed that no one ran the numbers on this woofer, so I pulled up Unibox.

The vented enclosure has a predicted F3 ~ 30Hz!!!!!!!! In Jed's comments, he does mention the outstanding extension of these drivers. It's not a subwoofer but if you were thinking of spending $400 on a TM + sub, this would be an great "compromise".

For those interested, sealed is predicted as F3~58Hz. Perfect for integration with a powered SEAS L26ROY, or 2.

[jkrutke]

They specifically didn't want me to use a certain competitor's cabinets for obvious reasons and the narrow baffle minimizes diffraction. Plus my cabinet calls for more bracing than you'll get with one of the prefabs.

Same thing I did with my ZD5 design - I went 7" wide because there was almost no diffraction ripple. Yet somehow I managed to need to notch filters in the woofer circuit. :E

With your design out, I don't see anyone building the ZD5 for a while unless they specifically want a tweeter that's an "outie" instead of an innie. :B

On a side note, I see that Scan-Speak has their own version of the XT25 now, $56. One has to wonder if there are any changes.

[Hdale85]

On a side note, I see that Scan-Speak has their own version of the XT25 now, $56. One has to wonder if there are any changes.

It sure looks identical to the Vifa counterpart....

http://www.madisound.com/catalog/pro...oducts_id=8646 Scan

http://www.madisound.com/catalog/pro...oducts_id=1181 Vifa

[Jed]

I see that Scan-Speak has their own version of the XT25 now, $56. One has to wonder if there are any changes.

Vifas are made in China with a lower price. I think that is the only difference. But I guess I could buy a pair to compare if I have time next month. I use the XT double magnet in a lot of designs. Price was $55 and now around $40. Go figure.

[AlanH]

ZD5 vs RBR

Same thing I did with my ZD5 design - I went 7" wide because there was almost no diffraction ripple. Yet somehow I managed to need to notch filters in the woofer circuit. :E

With your design out, I don't see anyone building the ZD5 for a while unless they specifically want a tweeter that's an "outie" instead of an innie. :B

The kit looks great and the price is startlingly low...I was wondering though (and I'm not trying to start a war - I just want to learn) about the differences between the two approaches. I know the ZD5 was set up with a full 2nd-order crossover and a ladder delay for the phasing. How does this compare to your approach Jed? What are the trade-offs of each approach and why did you make the choices you did?

Again...I'm not trying to start an argument or anything, I'm just trying to learn how two different designers put together high-performance systems using the same (or at least similar) high-performance drivers.

[Silversmoky]

Very nice Jed! Great looking kit! :T

[WalkinPaul]

Can't wait.

Hi, first post here. I just ordered the kit. Thanks Jed. The specs look almost ideal for what I'm needing. Been lurking here for about 2 hours a day for the past 6 weeks now, and these showed up. They look & I'm sure sound awesome and a great price too. Showed wife your pics and she said "Those are beautiful and you are so good at building those kinds of things, get them". 15 minutes later they were in my shopping cart and now are on the way here. Thanks Jed and Madisound for such a great deal and design. Now, I just got to build them. I'll keep you posted. :B

[Hdale85]

Hi, first post here. I just ordered the kit. Thanks Jed. The specs look almost ideal for what I'm needing. Been lurking here for about 2 hours a day for the past 6 weeks now, and these showed up. They look & I'm sure sound awesome and a great price too. Showed wife your pics and she said "Those are beautiful and you are so good at building those kinds of things, get them". 15 minutes later they were in my shopping cart and now are on the way here. Thanks Jed and Madisound for such a great deal and design. Now, I just got to build them. I'll keep you posted. :B

You are in for a treat I'm sure. Quality components and Jed's designs are always fantastic (I've built 2 of them now). Good luck with the build and be sure and post pics or they aren't real! (forum rules )

[Jed]

I know the ZD5 was set up with a full 2nd-order crossover and a ladder delay for the phasing. How does this compare to your approach Jed? What are the trade-offs of each approach and why did you make the choices you did?

I used an asymmetrical slope crossover that approximates LR4 phase characteristics. See Jeff B.'s excellent explanation of this topology here. The woofer is "relaxed" a bit and this helps to align the phase perfectly because the acoustic centers of the drivers are not aligned on a flat baffle.

A ladder delay aligns the phase of the tweeter with the midrange if using a shallow slope, such as LR2 on a flat baffle, where the acoustic centers are not aligned. Shallow slopes are sensitive to phase cancellations around the Fc, if the drivers phase is not aligned-- so the delay circuit helps to deal with the dip that would be the result without it.

The goal with this kit was to keep the parts count in the crossover to a minimum while using drivers that are up to the task of hitting the desired transfer functions. The 15W has a remarkably smooth response as does the SB29 in this baffle. The off axis response is very good as well with the selected crossover topology, so I'll leave it at that.

For every speaker there is a recipe. For this one we wanted simplicity yet effective design and to bring it all at a price never before seen with a Scan Speak driver.

Here are some of the notes about those choices and why I did what I did:

http://www.clearwaveloudspeaker.com/RBR/infoRBR.html

All crossovers can be more complicated, and I did have one crossover iteration that used about 6 more components, but in the end I was able to hit the same targets without the additional parts (or at least very close). It just took time. Sometimes less is more and the crossover does its job. Therefore, the crossover realizes what we set out to achieve.

Jed

[Jed]

Very nice Jed! Great looking kit! :T

Thanks!!! :T

Hi, first post here. I just ordered the kit. Thanks Jed.

You're welcome!

[Mazeroth]

Like everyone else has already said, well done, Jed! I have never considered purchasing a kit but this one may push me over the edge.

I have a new pair of PE 0.75 ft3 MTM cabinets that should work nicely with this kit. Hmmm...

[peter_m]

Congrats Jed,
Amazing value for a kit.

Peter

[benchtester]

It sure looks identical to the Vifa counterpart....

http://www.madisound.com/catalog/pro...oducts_id=8646 Scan

http://www.madisound.com/catalog/pro...oducts_id=1181 Vifa

It's amusing that Madisound's picture for the ScanSpeak shows the Vifa part number.

BTW: I noticed that at the ScanSpeak website they also offer a bucking magnet version. R2604-833000

[Jonasz]

It sure looks identical to the Vifa counterpart....

http://www.madisound.com/catalog/pro...oducts_id=8646 Scan

http://www.madisound.com/catalog/pro...oducts_id=1181 Vifa

The SS seems to lack the 5dB bump over 20khz of the Vifa. Also the impendance of the SS seems smoother between 1-2khz. The impedance at fs looks higher and more narrow on the Vifa. Visually I think the metal plate under the magnet looks a lot thicker on the SS, might be my eyes playing tricks on me though...

[Coconutout]

this kit seems almost too good to be true. i just had to pull the trigger finally something that can replace the void in my heart when i sold my big pair of the statements. not that the mini statements looked anything dismissal but a whole kit for the price of the scanspeak alone? :B my problem is though i'm still a noob and can't read the graphs too well so i don't know if this tube amp http://cgi.ebay.com/MING-DA-MC-84A-s...ht_3717wt_1165
would be enough to do the job at low volumes where i intend to keep it at. what would you say is the sensitivity on the rbr kit? MING DA MC-84A is reviewed to have huge power for its wattage.

[Rolex]

I picked up a kit. Should be amazing value. Stands are complete, and cabinets are being veneered right now. I can't wait to give them a listen.

[JonMarsh]

this kit seems almost too good to be true. i just had to pull the trigger finally something that can replace the void in my heart when i sold my big pair of the statements. not that the mini statements looked anything dismissal but a whole kit for the price of the scanspeak alone? :B my problem is though i'm still a noob and can't read the graphs too well so i don't know if this tube amp http://cgi.ebay.com/MING-DA-MC-84A-s...ht_3717wt_1165
would be enough to do the job at low volumes where i intend to keep it at. what would you say is the sensitivity on the rbr kit? MING DA MC-84A is reviewed to have huge power for its wattage.

Jed's graphs on his web page are not normalized to driver working sensitivity, so there's no way you can predict this from his data. The SS 5" woofer is about 85 dB/watt on IB, so in a box with BSC, it will be between 80 to 82 dB/watt, depending on the the degree of BSC used in the design, and the inductor resistance losses. Madisound offers an improved performance kit with AWG14 inductor and ESA Clarity caps; might be worth looking at.

I have to chuckle a bit at your last statement; I'm sure it's meant with the best of intentions, but saying that an amp offers huge power for it's wattage sounds like an oxymoron. Of course, the amplifier may be under rated, or it may clip more gracefully than some other designs. It does have taps for both 8 ohms and 4 ohm loads, so it is possible to optimize the power transfer for the speaker you have (rather than not having enough volts or enough amps depending on the impedance). The impedance only rarely dips to 8 ohms, so this amplifier should have no difficulty driving the speaker. However, tube amps with high output impedance do exhibit frequency response variations by interacting with the load, so the impedance rise at 60 Hz may affect bass quality with this amplifier, and the rise in the midrange around 1200 Hz to about 18 Ohms may result in a forward characteristic in this frequency range, due to the power amplifier. 13 watts should be OK for listening levels up to about 90 dB peak.

[cotdt]

this kit seems almost too good to be true. i just had to pull the trigger finally something that can replace the void in my heart when i sold my big pair of the statements. not that the mini statements looked anything dismissal but a whole kit for the price of the scanspeak alone? :B my problem is though i'm still a noob and can't read the graphs too well so i don't know if this tube amp http://cgi.ebay.com/MING-DA-MC-84A-s...ht_3717wt_1165
would be enough to do the job at low volumes where i intend to keep it at. what would you say is the sensitivity on the rbr kit? MING DA MC-84A is reviewed to have huge power for its wattage.

EL84's won't give you much power, maybe 12W in push-pull (I've built such an amp). They do give a nice bass boost at the impedance bump, though.

I would recommend a 100W amp for these kind of speakers.

[Hdale85]

I don't think these particular speakers really need 100 watts. Also if he's interested in tube amps he's pretty unlikely to get a tube amp with that kind of power. These speakers are made for critical listening and honestly could probably do with 30 watts at high outputs but he said he was looking for moderate volumes so something around 10-15 watts could work quite well.

[Jed]

My Ayre AX7e plays these plenty loud, which is 60 watts into 8 ohms.

[JonMarsh]

I would expect so- just as mine does with the Modula MT or Neo D CC. But then we have the folks shooting for 95% efficient systems with horns/CDs and pro sound drivers, so I guess it takes all types! Those may do better with a 12 watt per channel tube amp.

[JonP]

Hi, first post here. I just ordered the kit. Thanks Jed. The specs look almost ideal for what I'm needing. Been lurking here for about 2 hours a day for the past 6 weeks now, and these showed up. They look & I'm sure sound awesome and a great price too. Showed wife your pics and she said "Those are beautiful and you are so good at building those kinds of things, get them". 15 minutes later they were in my shopping cart and now are on the way here. Thanks Jed and Madisound for such a great deal and design. Now, I just got to build them. I'll keep you posted. :B

Hi Paul...

Welcome, congrats, and... she sounds like a keeper!! :T

Keep us posted and post some pics!

Jon

[Coconutout]

xO i didn't word my last sentence properly but what i meant was that the reviews comment on how powerful it sounds despite its actual output. my last el84 amp that was modified from an organ amp also had an impressive bass until my dog blew out the tubes by licking them :P i always come here right before going to sleep... helps me to have sweet dreams about systems i wish i'd have.