4530 Clones

[Mike C]

Hi guys, I bought a pair of 4530 clones today. I missed out on the 4520's on Ebay so I thought I'd give these ago. I loaded them with my 2220-H's and mounted a pair of 2370/2420 combos on top. They sounded ok but not very musical. So after trying a couple of other bass drivers ( K-140's and even 2235's) I went back to the 2220's. So then I replaced the horns with my 909/511b combos and everything started to come together, I crossed them at 500hz and turned down the 909's a little and was very suprised how smooth the sound became. I will need to spend some more time with them but so far pretty cool. I may hook up one of my 18's to find a little more bottom-end. I may try some 808's on the 511's as well and see how they go.
Some thoughts would be appreciated. Also this week I hope to recieve a pair of E-145's I'd like to try them in the system as well.
Cheers!

[Earl K]

Hi Mike

Have you built any RC horn HF response compensating networks for those 511/909 combos. I forget what impedance your 909s are. If they are 16 ohm then the resistor value used would be 16ohms paralleled to either a 1 or 1.5 uf cap . This twin component network is then put in series with the horn driver. It suppresses the midrange below the crossover point ( as determined by the cap ). This means of course that the gain needs to be turned up on the HF amplifier ( or at the crossover ). You are biamping this, aren't you ?
- Bypassing the RC combo with a bunch of .01 uf polystyrenes & a single .5 uf polypropylene does wonders at putting "air" back into the horn driver.

I find these simple networks are all I need on exponential horns to give enough high-end ( without resorting to electronic EQ or a tweeter ).

regards < Earl K :)

[Mike C]

Hey Earl, thanks for the advice. Well I've been out spending again today, I bought off the guy I got the 4530 clones off - a pair of double 15" folded horns. these things are huge !! 49"h x 35" w x 32' deep. I loaded them with 4 2220-h's, the bottom end is to die for. I used my 2123-h's and 2370/2420 horn combo with them. The sound has got so much depth and realism, the bass notes are dead tight and go way down. I don't think I'll bother hooking up my 18's with this rig. My next step is to buy some new (s/h) electronics. Have you used the new DBX Drive rack PA ? also it's time for some amp up dates. Anyway now I know what all them bass horn guys rave about, apart from their size I don't think there would be much around that would have a nicer bottom end. Do you think a 2" horn would be much of an improvment over the 2370/2420 combo? maybe a pair of Widget's Westlake copies and 2450-J's ???? what do you think?.
thanks again
Mike..............

P>S what crossover points would you consider for my existing combo?/;)

[Earl K]

Hi Mike

I can see you're spending some money - are you also moving into a french castle soon ? :rotfl: :spin:

The DBX Drive Rack is quite excepted in the SR industry. Also I know of a well respected studio here in Toronto that is using it to drive their large SOTA monitors.

Having said that, I had a bad experience with one. Within a year of their release into the market (a while back ) - I had one sitting on my desk for a long term evaluation. The thing developed an intermittent display problem. It went bonkers as only a DSP device can. All the audio circuitry and its' software driven patching/routing remained intact - a good thing, a really good thing . Anyways, this problem was unique to me - & it only happened when the unit was in my possession. The dealer & the Canadian distributor thought I was nuts. Eventually ( after a year ) this problem manifested itself quite severely to the dealer ( who also couldn't get the distributor to accept these facts ). Finally the unit made its' way back to the distributor who had it some while before the unit lost its' mind on their bench. There were other things about the unit I disliked. Most notable was the convention they used when laying out the XLR outputs and the menu driven display. If I remember correctly it was "backwards" to the convention I use & strongly prefer. The convention I want is; For the outputs to be ( left to right - bass to treble ) & for the display ( top down to bottom - tweeters to bass ) . The unit does offer the latitude to reroute / rearrange / or soft-patch to the outputs of your choosing. But one does this at ones own peril in the SR industry. Since it's not "their" convention - anyone else fiddling with the unit will start any trouble shooting exercise out in LALA land. Not a good thing. So, I avoid the unit - since I'm a creature of habit . I also find all DSP stuff is still a bit unstable - & as such I prefer to pay as little as I can since it's effectively a disposable piece of gear if it starts "blinking" at me. .:shock: :wave:

Yes, I think a larger format compresson driver will work better for you with that much horn-loaded bass/midbass . Mr Widgets Westlake style horns should be a no brainer if you've got the cash. They will be a horn that should follow you around to many different residences and decors. Are these bass horns 4520 scoops or something else ? Can you see the woofer or is it buried in the box. If it's buried your crossover point will need to be lower since a bent horn doesn't allow much above 300 hz to wind its' way through the folds . If it's a scoop and you can see the 2220 drivers then you can really choose the crossover point to suit your own tastes and for what the driver will comfortably reproduce . Your 8024 will help you analyze the acoustic outputs to come to that decision.

regards < .Earl K :)

[boputnam]

Originally posted by Earl K
The DBX Drive Rack is quite excepted in the SR industry. Now that syntax is quite ambiguous, particularly wrt following discussion. You being clever, Earl? Is it good, or bad...?

Interesting Thread...

[Earl K]

Hi Bo
- Nice catch :rotfl:
- No I was trying to offer a balanced perspective - the "excepted" word was meant to be "accepted". It looks like one side of my brain over-ruled the other and snuck that past the censor , re; the balanced voice thing . :flamer:
- That's what I get for posting before the caffeine kicks in . :D

regards <. Earl K :)

[Mike C]

Thanks for the reply Earl, the bins have drivers tucked away inside, I had to undo a sqillion screws to get to the speaker baffles. I did play with the crossover a little, and found 200hz to be about on the money. My 8024 is not very well at the moment, there seems to be a lot of interferance coming through on the eq side of things. I did have a bit of a look at the owners manual and it did go into the connecting cables and their termination so maybe i'll look at that. This was another reason for looking at the DBX driverack PA. There are some 2451 compression drivers on 2332 horns on Ebay at the moment have you had any experience with those? What would be your favorite 2" cd of any brand, I want something that is silky smooth. Thanks again mate.
Mike

[Earl K]

Hi Mike

No I don't have any experience with those drivers. By all accounts a great driver with likely another typically underdamped SR style diaphragm from JBL . :flamer: ( my 2 cents )

I really think its worth paying attention to what JBL does with its compresson drivers in its' K2 products - when it comes to home use of its' compression drivers ( especially if you can see down the throat of the horn to the bug screen and there's little or only a slight throat squeeze ). Most of the K2 diaphragms are damped with a plastic coating ( aquaplas) on the titanium or berylium domes - the rare exception is an aluminum diaphragm in the 435al driver.
IME, translated, "silky smooth" has got to start with the right diaphragm choice. Even JBLs' newer berylium diaphragms are plasticized when used in a HiFi setting. For me; No plastic on the titanium means SR ( under-damped ) - developed for maximum output. That 2332 horn offers very little loading in the throat area - so with that standard titanium diaphragm I'd be very concerned about an "over-excited - underdamped" output .

I don't have a favourite driver ( they are mostly just motors from my perspective ) but my favourite diaphragm type is the aquaplased titanium 2450SL . Maybe if I owned TAD berylium types , I'd have a different opinion - but that's just academic because I don't . I suspect that I'd really like the plasticized berylium 435be .

IME; the easiest driver ( by far ) to incorporate into a hifi setting is the Altec 288-8K. They are obtainable and usually quite affordable. The domes surface area is twice that of a 909/2426 but only 1/2 as large as a large format JBL. This amount of square inch area is now what it seems that JBL has finally adopted as its paper to metal ratio ( woofer to compression driver dome area ). This ratio is very significant for establishing a proper voicing for the whole system . The knock against these drivers is that they could have 2 diaphragms that don't match. Either because of aluminum fatigue or because of Altecs well-known QC problems from that era or becausein the SR setting they are coming out of - one was a replacement. Still , Bill at GPA sells these diaphragms - though I can't personally vouch for how they stack up against a bona-fide original Altec Little Maestro type ( silk-screened on the dome ). And I don't know if Bill offers any performance quaranty ( like a response curve of +/- 2 db after proper installation ) .

regards <> Earl K :)

[Mike C]

A pic of my system sorry about poor quality

[Mr. Widget]

Mike,

Please try posting your photo again.

Earl,

What horn(s) do you like or use with your 288-8Ks? You may have posted this before and I missed it, if so just a quick reiteration would be appreciated.

Widget

[Earl K]

Hi Mr Widget

- Here's Mike Cs' system . He sent me the large photo when he couldn't post it. I've downsized it for posting. He must me snoozing by now.

- Right now I rarely use my Altec 288-8Ks because I'm listening to capacitors. The double sized diaphragm of the JBL 2440/1 driver really facilitates this exercise. When I do listen to the Altecs' - it's mostly through my Selenium HL 14-50 round mouthed metal horn ( with their 1.4" to 2" adapter ). This 45° horn is essentially a 2311 that has a properly finished/terminated horn bell. As such, the mouth size is larger than a 2308 lense. It works well for "bowling-alley" setups like my living room. I do prefer the larger JBL driver on this horn. Adding the extra throat length from the adapter really underscores the fact that its a 45° horn. The Q seems to change with the extra throat length. I still need to search out a horn for these 288s when I finally settle down and complete my MTM setup. I have no idea when that might be.

regards <> Earl K :)

[Mike C]

Hope this pic is a little better.
Folded horns: 2 x 2220-h in each enclosure (49'hx35"wx32"d)
Mids: 1 X 2123-h
horns: 1 x 2420-h or 909-16-a/511b
Sub: 2 x 2241-h in sectioned encl (each 6.25 cuft)

Today I puchased a pair of Manteray horns to try and I will buy a pair of Altec 288-16k's to try. I need to save a little to afford Mr widgets Westlakes though I'm hell bent on getting a pair. Will the Westlakes work with a 1.4" exit driver ?

[Mike C]

A pic of the folded horn

[Mr. Widget]

Hi Mike,

When you are ready for the horns let me know.:)

With a 1.4" exit driver you will need a JBL 2330 adapter. A fairly rare item, but there are similar adapters from other companies as well.

I haven't tried a medium format driver on these horns, I did try a small format 2420 and was not thrilled with the results. If you have a chance I would recommend you try a 2397 on them before you order a pair of my horns, or alternatively when you are ready, I guess I could lend you a horn to try out.

Widget

[Mike C]

Thanks for the reply Mr Widget, a 2397 is a hard item to find around these parts. I think I'll keep saving for a pair of your horns. My system is pretty ugly, so a pair of your horns in cheaper material would be all I need and If I get them off you unassembled I'm sure that will make them easy to send to Australia.( the system would not do justice to a pair of those things made in exotic timbers) As I stated I purchased a pair of 1.4" Manteray horns today and I have acces to a pair of 288-16-k drivers so that will give me something to play with. In your opinion what JBL driver suits the Westlake, and would something with a pair of slots be best. The 2370/2420 sounds of but I'm sure it gets a little bothered at higher volumes. I think the balance of the whole system would be nicer with a 2" driver/horn combo. The bottom end in this system is something to behold let me tell you, but the mid /hf seems a little colourd compared to the 4350's I had some time back. If this system had the 12" 2022-h I think it would be nicer in the 200 hz up region. I'll look for a pair of them as well. My plan is to mount the mid bass drivers and slots in the mouth of the folded horn and mount your horns on top of the enclosers. This will make " doctor evil" look a little less intrusive. I plan to have a couple of grills made for them when after I sort out the driver complement. Finally I have to source some new amps out as they are all getting stretched with this system.
Mike.

[Ron K]

Those bass horns look like the University Classics. I have a pair I built and really like the way they perform. I preferred a compression driver / horn for mids. I had 291/511 horns on mine. Ron

[Mike C]

Hey guys, today I puchased a pair of 288-16g's. I put them into the Manteray horns I got the other day, and I can't put into words how exited I am about the sound. So smoooothh, detailed and natural. I cross them at 500hz into my folded horns. Tomorrow I pick up a pair of 4560 bass horns, a pair of 2350 horns and a pair of Cabaret 3- ways ( swapping some of my old gear.) I can't wait to try the 288's with the 2350's- these horns are huge!. Would they be similar to the Westlakes???
Mike.

[Earl K]

Hi Mike

- Good score with those 288-16g drivers. :yes:

To mate them on to the 2350 horns will take an 1.4" to 2" adapter.

JBL made one, the 2330 (usually impossible to locate )

Altec had the 33710 adapter (also just as tough to locate a pair )

Selenium makes a real nice copy of the old 2330 . This well made part is available throughout the world from what I gather. Its' part number is the AD35-50. It comes with nice permanent foam gaskets attached to both faces. Plus I think it ships with a set of 4 nuts & bolts. This part is usually worth @ $10.00 but I see the price has tripled or quadrupled in the last year ( at least in the land of free enterprise). It has now reached the area of "whatever the market will bear". This adapter is available from Parts Express (http://www.partsexpress.com/pe/showdetl.cfm?&User_ID=15892998&St=1480&St2=65363888&St3=-48072886&DS_ID=3&Product_ID=6337&DID=7) though I'd be reluctant to pay the type of money they are asking ( unless this is now the only option ). This is an exceptionally high amount of money for a 1-shot adapter. For that price it should offer the option of adapting to JBLs' own 1.5" 4 bolt standard layout ( as well as the 4 bolt europeon standard for 1.4/5" ). The seleniums flange for the 1.4" end is too small to drill these other 4 holes in yourself.

E.V. May make a 1.4" to 2" adapter but I can't find a part number for it - if they do .

2350 vs 2397 : Really they are two different beasts . The 2350 is not an operational stable-mate of the 2397 or Westlake horn. The 2350 radial is an exponential in the vertical axis mated to a straight conical in the horizontal axis. The 2397 closely follows the original description of a parabolic horn with its' 2 to 1 reduction. The "parabolic" portion is actually the throat reduction/constriction of the 2" down to about 1". The bell/lips maintain this spacing till the sound is released and diffracted to some degree. The internal "vanes" in the 2397 style horn form small internal exponential horns working in the horizontal-axis - further distancing the 2397 from the 2350 "radial" which is conical in this ( horizontal ) axis.
The throat sections of the Altec Mantaray and JBLs 2360 series of BiRadials have parabolic sections.

regards <. Earl K :)

[Mr. Widget]

Martin Sound has the Selenium adapter and has the Martin Sound part number 1883. They are $26.24 each. From comparing the catalog photo and the JBL 2330 catalog photo they have different overall lengths. This would result in the Selenium having a faster rate of flair. I am not sure if this would be audible,

http://www.martinsoundpro.com/PDF_files/adapters.pdf

http://www.martinsoundpro.com/

[Earl K]

Ah ! Right You Are (Mr Widget)

The JBL is longer at 60mm vs the 50 mm for the Selenium . It would be interesting to try to find and then measure the discountinuity as the 2 flair rates meet & then "revector". Though, I doubt if I'll ever see a 2330 to be given the chance. I imagine there's a 5° ( or so ) difference in the flair rates of the two adapters.
I sometimes use these Selenium adapters - but then they are usually on Selenium horns.

regards <> Earl K :)