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View Full Version : Newby looking for advice for DIY project (4345s or?)



CosmicC
05-05-2012, 06:18 PM
Hi there, I'm new to these forums (1st post!) and I'm looking for some advice from the audio sages here.

I work for my family's business in Toronto, we recone speakers and buy/sell/trade audio equipment but our focus and expertise is more professional audio oriented BUT recently we received a Crown Macro Reference amplifier in a trade in (any thoughts on this amp? My limited research has found only positive reviews). My father is intending to try and sell it but I have stayed his hand, because I'm thinking I might embark upon my 1st DIY speaker creation quest!

The Macro Reference makes 760 watts at 8 ohm. With that kind of power I was thinking I should build some large format speakers. I happen to be a big fan of JBL 2245s, and we happen to have the frames and parts handy so I could build myself a pair (have a few extra too if anyone is looking) so 4345s seemed like the natural and intriguing option and based on the limited digging I've done on this forum I gather the residents here think very highly of them. I know 4345s can be bi-amped, I would probably lean towards using them full range to realize the potential power and clarity of the Macro Reference. I know a great carpenter, and I probably have/can get most of the components. The biggest block for me is the x-overs. I'll keep looking on these forums for threads on the 4345 cross-overs, but advice/thoughts on how to go about that would be handy. Can I build them myself?

I'm not married to notion of building 4345s so if anyone has suggestions of large, fairly high output/power handling systems other than the 4345s, I'm game to check out other ideas.

I also thought it might be fun to come up with a design using some more modern components with the JBL 2245 as the anchor. I know I'll probably get pooped on and maybe rightly so for thinking I can reinvent the wheel when the 4345 is apparently already astoundingly awesome... BUT.. Hey, its an old speaker made with old components. Maybe with newer and more readily available components you could achieve a higher maximum volume while maintaining the sound quality and that bombastic bass ;)

Thanks,
Chris.


ps This forum seems like its has just vaults and vaults of threads and probably all the questions I just asked have already been answered.. so if you've already answered them 10 times if you could just link relevant threads I'd appreciate that.

BMWCCA
05-05-2012, 07:31 PM
ps This forum seems like its has just vaults and vaults of threads and probably all the questions I just asked have already been answered.. so if you've already answered them 10 times if you could just link relevant threads I'd appreciate that.
Heather has already done much of the heavy-lifting for those researching all the 4345 threads here: http://www.audioheritage.org/vbulletin/showthread.php?16967-4345-References-Thread&p=171841

The crossover design is well-tried, and the designer's comments should have you pursuing the bi-amp solution regardless of the amp used.

I'd love to try your Crown on the bottom of my 4345s. They sound so damn fine with the PS-400 and PS-200 I can only imagine what the Reference would do!!! :thmbsup:

Welcome aboard. :cheers:

CosmicC
05-05-2012, 11:58 PM
That article from the designer is fascinating! Thanks for the lead.

Lee in Montreal
05-06-2012, 06:08 AM
Welcome to this forum. You'll find tons of valuable info. Are you related to Santon Audio in Markham by any chance?

CosmicC
05-06-2012, 10:51 AM
Yes sir.

Lee in Montreal
05-06-2012, 11:09 AM
Yes sir.
Great. Then have your dad order original JBL recone kits for your 2245 and whatever other drivers you'll use in this project.

Mr. Widget
05-06-2012, 12:45 PM
I'm not married to notion of building 4345s so if anyone has suggestions of large, fairly high output/power handling systems other than the 4345s, I'm game to check out other ideas.

I also thought it might be fun to come up with a design using some more modern components with the JBL 2245 as the anchor. I know I'll probably get pooped on and maybe rightly so for thinking I can reinvent the wheel when the 4345 is apparently already astoundingly awesome... BUT.. Hey, its an old speaker made with old components. Maybe with newer and more readily available components you could achieve a higher maximum volume while maintaining the sound quality and that bombastic bass ;) It sounds like you want a system that will scare the neighbors and be capable of live music SPLs while still sounding better than the typical PA system.

For that, there are newer better options, but at a significantly greater cost. I would go with the 4345 if you are interested in a big and loud system, or go to the 4350 if you want to play it even louder and with more slam... though with a little less finesse. If you go with a biamped system you could create a hybrid with a single 2245 below and the 4350 upper crossover and components. Beyond that, if you delve into the dark arts of speaker design or design bashing, I can guarantee it will be years before you match the level of quality you can achieve by carefully copying the work of the experts. You can read hundreds of accounts by folks on the internet who have succeeded in performing these miracles... creating speakers that are better than anything else on earth... yeah, sure.


Widget

BMWCCA
05-06-2012, 01:12 PM
I would go with the 4345 if you are interested in a big a loud system, or go to the 4350 if you want to play it even louder and with more slam... though with a little less finesse.


Yeah, I guess their huge size makes people forget their gentle nature. That's okay, it happened to me when growing up, too! ;)

The 4345 (well, at least mine since they're the only ones I've ever heard) is so fantastic at handling any kind of music even at low levels that allow conversation in the same room that the previous owner of my pair referred to them as "The Velvet Sledgehammer". Gentle Giant would be apt, too. It's not easy to forget they're in the room but that never interferes with the music!

And when I play them loud, I don't really think they're that loud! Funny how clean, undistorted sound can creep up in volume without sounding "loud". They certainly are capable of reproducing live-performance level SPLs in my house. But then even my old 030s used to do that nearly every weekend outside on my back porch in my college days on an 800-acre farm facing the Blue Ridge Mountains with just a Crown D-150 helping out.
:applaud:

CosmicC
05-06-2012, 07:57 PM
Thanks for the posts guys.

4350s + 2245 sub(s) might be just a littttttle too big. 4350s alone are too big for me right now too to be honest, and they lack the key ingredient that is the 2245s. Which was my favorite speaker even before I read the praise of it in that article by the designer.

I'm thinking 4345s is the way to go. How do you manage the active cross-overing in the hi-fi world? I'm used to using either dbx/ashley cross-overs units or digital processors. Are those considered too corse? I like the Ashley Proteas for PA use.

I guess I might need to sniff out a couple more amps.. hrmm..

BMWCCA
05-06-2012, 09:00 PM
Well, I'm using the Ashly XR1001 because it was available at a reasonable price and others here who know this stuff far better than I do recommended it as a reasonable solution that seemed to work just fine. If there's any problem with it, I'm blissfully ignorant of its drawbacks. :dont-know:

Marchand is what I've been told to aspire to, but until I hear one in my system I'll remain happy with what I've got.

Mr. Widget
05-06-2012, 09:10 PM
Thanks for the posts guys.

4350s + 2245 sub(s) might be just a littttttle too big. 4350s alone are too big for me right now too to be honest, and they lack the key ingredient that is the 2245s. Which was my favorite speaker even before I read the praise of it in that article by the designer.

I guess you misunderstood me. I was suggesting a single 2245 with the 2202, 2440/41, and 2405 of the 4350. As for their relative sizes, they are both 10 cu ft systems.


Widget

speakerdave
05-06-2012, 09:26 PM
One advantage of the 4355 upper three drivers combined with the 2245 is that you would be using a large format treble driver and could therefore upgrade to the Truextent beryllium diaphragm. You could avoid some expense by using the 2445 instead of the Alnico 2440/41, but that option adds some complexity to building the dog box for the midbass cone. Find 4313B's thread on his 4345 build.