Conquering a square room (with Altec 2459a OBs)

[rtsyrtsy]

Parinig din...sa susunod. Sana bago ako umalis unit (2-3 weeks time).

[vintage_dog]

Parinig din...sa susunod. Sana bago ako umalis unit (2-3 weeks time).

russ...sure. let me know when you're free...

[mozilla]

Arnold.

James & I loved it. He texted me yesterday that he made an improvides open baffle with his Altex 403a's (?). Same tonality daw with your 2459a's. He's quite excited to build one.

I'll post pics after I go back to Cebu next month.

Oo nga nakalimutan yung eraser.

[arnoldc]

moz, good for him. just text me if you want to pass by for the eraser for oscar and the others.

[mozilla]

Sure will do.

[arnoldc]

v_d, ichabod has 403A too and according to moz's post above, he liked what he heard.

personally, between the fostex and the altec drivers, i'd take the altec anyday. to me, the altec has the "right" sound.

[ichabod]

Arnold,

Thanks again for the opportunity to hear those altecs on open baffles. When I got home sunday, I hooked the altecs 403As, no baffles, just on the floor to check its tonality. And I heard exactly what my memory tells me of your altecs on OBs.

The Altecs full range do have an open seamless sound. With two way three way systems, you can hear an xover separation. The altecs sounded clearer and smoother, like the sound is compleat and whole; total if you like over a wide sound window. Not difficult to hear sonic nuances of the recording, and the highs seem to be well controlled and stays within the bounds of the sound field, naturally coherent to its overall sound. I could sense a more contented and happy look on Arnold's face (this was our second visit to him) when we listened to his system. His confidence was simply there. Yes, the altecs do have the "right" sound!

I wish to thank Joel too for inviting us for a listen to his system. His cnsist of an altec pair of woofers, and horns that take care of the mids and highs. To my pleasant surprise, this is my first time to hear both woofers and horns tapered so well (ingenuiously controlled) to sound like a typically good midrange, and separate tweeter. But with typical mids and tweets, you don't get as much a broad soundfield as these horns. I suspect Joel has some well-kept secret recipe employed in the xover that made these altecs work very well in a home environment. Care to share that secret Joel? Grant and I met and listened with Rex, who is also an LS 3/5a user. It seems to me LS users are at this point also entertaining the propspects of going SET with Altecs. And why not? I like what I heard! Clear and natural as the recordings would allow! It is I think that midband presence that make these altecs hard to ignore once you've tried them. That was indeed some horny night over good food and red wine, with a vintage Garrard grooving those LPs! Surprisingly no "pops and ticks" there. A very forgiving setup from Joel on what could have been otherwise a bullish horn!

[vintage_dog]

am not sure if joseph (setup1) is reading this thread, but thanks to him for sharing his plans and learnings on OB. i believe the baffle specs came from joseph too. thanks josph.

have some questions:

1. any comments on 2459a vs 403a? i have both but have the OB for the 2459s only. the 403a is in a bookshelf baffle. i find the highs rolled off on the 403a and we experimented using a tweeter to bring out those highs. will they sound more extended in OBs?

2. the local plywood we used are light in weight and i can feel the entire OB vibrate with the music. perhaps that helps in the sound as well . would a heavier more solid wood be better. what improvements in sound can i expect?

3. there is a slight bump in the mid-bass which i suspect comes from the 2459a interaction with the floor. will run a frequency sweep to find out what frequesncy that is. it's not distracting but noticeable.

4. where can we get specs for these "budget" drivers?

5. will other drivers work as well? am thinking of the fostex. these are readily available. am having 3 sets of OBs made this week to play around with...

[setup1]

am not sure if joseph (setup1) is reading this thread, but thanks to him for sharing his plans and learnings on OB. i believe the baffle specs came from joseph too. thanks josph.
have some questions:
1. any comments on 2459a vs 403a? i have both but have the OB for the 2459s only. the 403a is in a bookshelf baffle. i find the highs rolled off on the 403a and we experimented using a tweeter to bring out those highs. will they may sound more extended in OBs?
2. the local plywood we used are light in weight and i can feel the entire OB vibrate with the music. perhaps that helps in the sound as well . would a heavier more solid wood be better. what improvements in sound can i expect?
3. there is a slight bump in the mid-bass which i suspect comes from the 2459a interaction with the floor. will run a frequency sweep to find out what frequesncy that is. it's not distracting but noticeable.
4. where can we get specs for these "budget" drivers?
5. will other drivers work as well? am thinking of the fostex. these are readily available. am having 3 sets of OBs made this week to play around with...

Hi Francis,

Thanks for emailing me directly! I wouldn't have noticed the thread because I was practicing....anyway it looks like OB building season from around the world. During the holidays I received emails from quite a few OB builders here in the USA, S. America and Europe.

Answers:
1. I never had the chance to compare the 2459A head to head with the 403A. My comment on the 403A is in the SP homebrewer article I wrote back in '97. Here's the link to the pdf file: http://members.myactv.net/~je245/homebrewer.pdf
Please bear in mind that my "seemingly less than enthusiastic view" of the 403A was due to the fact that I was comparing it to the 755A and 755C which are in another league. The 2459A I heard was a gift from John P. to Ding which I brought back to the USA in early 2003. One thing I liked about the 2459As in Ding's OB was the midrange "snap". I think the 403A has less of that IIRC but it did have a nice alnico type HF. But you guys should just try and compare and take my comment with a grain of salt.
2. The OB in my "hideout" system is also built from local plyboard/plywood, nothing fancy and I think it performs just as well as the heavier and drier 8 year old Birch Ply I have here in the States. Yes the OB vibrates with the driver, you should experience the vibration in Ding's OB when loaded by his 604-8G at full steam! My point is, we've all been "educated" by high-end ideology that the cabinet should be damped, dead and inert = "neutral sound" or lack of coloration. But does neutral sound = accurate? In the end this jargon of adjectives is quite useless since in as much as we want to "recreate" the sound of live music in our listening room, record reproduction is still an illusion. So anything that contributes to my enjoyment of recorded sound IMHO is welcome, this includes the OB vibrating with the driver. Besides it is a flat baffle [not a cabinet which has to contend with standing waves inside] and the only potential coloration of sound with this type of speaker is the nature of the driver itself [just like Quad ESLs and Maggies] and the driver/OB interaction with the room. So rest assured, the last thing to worry about is the quality of plywood unless it is aesthetic reasons. But everyone is entitled to their own tweaks [butcher block, acrylic/plexiglass, MDF, composites or other high tech materials] as long as it enhances ones musical satisfation!
3. The bump you hear can be caused by several things - ancilliary equipment, source or even the room itself. All I'm saying is before doing anything drastic, make sure you've ruled out these other factors. If you are sure it is a floor interaction, try putting an area mat or carpet first and see if this cures the problem. Placement in the room can also cause this mid bass hump especially if the OBs are close to the corner or back wall.
4. I've never seen or heard of the 2459A here in the USA. Ding has also inquired from his network of dealer friends who export to Japan and none of them have heard of this 8" driver. We speculate that this is a Taiwanese OEM unit from the 70s-early 80s sold by Altec exclusively for the Asian market. My gut feel is, you guys have a better shot at getting specs for these drivers than us.
5. I've listed all the drivers I've tried on my OB plus others at my site:
http://members.myactv.net/~je2a3/open.htm
Unfortunately I haven't had a chance to use a Fostex. But there are a few people who've posted good things at the Audio Asylum using FX200, FF225K, FE207 and etc. The best sounding Japanese driver I've used in the OB is the Lafayette SK98 aka as the OEM Pioneer PIM8. Unfortunately they are vintage but you can still score a pair of these at eBay ~ $200/pr. I'm sure there are a lot of other possibilities if one does not have the budget for 755s, check these pages at my site for ideas on what to hunt for:
http://members.myactv.net/~je245/vintagebudgetspks.htm
http://members.myactv.net/~je2a3/vintag ... rivers.htm

Hope this helps!

JE

[setup1]

Arnold,

Thanks again for the opportunity to hear those altecs on open baffles. When I got home sunday, I hooked the altecs 403As, no baffles, just on the floor to check its tonality. And I heard exactly what my memory tells me of your altecs on OBs.

I wish to thank Joel too for inviting us for a listen to his system. His cnsist of an altec pair of woofers, and horns that take care of the mids and highs. To my pleasant surprise, this is my first time to hear both woofers and horns tapered so well (ingenuiously controlled) to sound like a typically good midrange, and separate tweeter. But with typical mids and tweets, you don't get as much a broad soundfield as these horns. I suspect Joel has some well-kept secret recipe employed in the xover that made these altecs work very well in a home environment. Care to share that secret Joel? Grant and I met and listened with Rex, who is also an LS 3/5a user. It seems to me LS users are at this point also entertaining the propspects of going SET with Altecs. And why not? I like what I heard! Clear and natural as the recordings would allow! It is I think that midband presence that make these altecs hard to ignore once you've tried them. That was indeed some horny night over good food and red wine, with a vintage Garrard grooving those LPs! Surprisingly no "pops and ticks" there. A very forgiving setup from Joel on what could have been otherwise a bullish horn!

Hi James,

I'm glad you were able to visit Joel. I'm not surprised you liked what you heard. Joel and I were also LS3/5A users for a long time.

There are no tricks in that crossover. I can attest to that. It's a simple 1st order 6 dB/octave slope using paper in oil can type caps and generic coffin type cement resistors. The "secret", if I may call it that is his pair of keen ears plus a lot of sweat and patience experimenting with the x'over point and L-pad adjustment to properly align the horns with the OB/414 bass.

You don't need to have a SET amp to experiment with OBs, a nice vintage PP EL84 amp will be a good place to start. Good luck and I hope you will build an OB for your 403As soon!

JE

[ichabod]

Hello JE. Nice to know that you're listening.

Yes, we had a grand time auditioning the altecs, both at Arnold's and Joel's. Both gentlemen were kind to have us on such short notice. Wish to thank you though for those OB drawings Arnold shared with me. I'm convinced how well might a single driver do what some 2-3 way systems can overdo at. I like the focus of the LS and this is indeed quite natural on those altec full rangers. So it's not a struggle or some battle in the mind to like its sonics. There's that obvious similarity that permeates between them, but the altecs win on iots sheer driveablity and more openness to its sound. I always tell my listeners to the LS and those who own them that I always bring my bass tone control to almost zero on the LS due to its heavier tone for such a small speaker in the bass, the reason why you need to keep them away from walls, specially the one in front.

With Arnold's and Joel's, more space is gained. One need not worry or hurt one's back on placement. Can't tell yet whether these OBs will improve or shift in tonality with regular room treatment or those ideal often used placements. We heard Arnold's in a carpetless wooden floor in his upper chamber, I would say the best way to diminish the sound of the LS 3/5a on less solid grounds, and at a placement that's near wall.

But on those altecs what I heard was an open and clear sound at where we were! Quite amazing. Knowing those speaker placement rules, and then breaking some to get away with a clear good sound must be quite a feat by itself. What a friendly speaker this is to an audiophile, but maybe not so to the wife because of their plain jane looks. I'll leave that art to another of the husband's courting.

Might have the OBs by next week. Will sure leave some impressions again.

[setup2]

Arnold,


I wish to thank Joel too for inviting us for a listen to his system. His cnsist of an altec pair of woofers, and horns that take care of the mids and highs. To my pleasant surprise, this is my first time to hear both woofers and horns tapered so well (ingenuiously controlled) to sound like a typically good midrange, and separate tweeter. But with typical mids and tweets, you don't get as much a broad soundfield as these horns. I suspect Joel has some well-kept secret recipe employed in the xover that made these altecs work very well in a home environment. Care to share that secret Joel? Grant and I met and listened with Rex, who is also an LS 3/5a user. It seems to me LS users are at this point also entertaining the propspects of going SET with Altecs. And why not? I like what I heard! Clear and natural as the recordings would allow! It is I think that midband presence that make these altecs hard to ignore once you've tried them. That was indeed some horny night over good food and red wine, with a vintage Garrard grooving those LPs! Surprisingly no "pops and ticks" there. A very forgiving setup from Joel on what could have been otherwise a bullish horn!

James,

Your welcome and it was a pleasure to meet you and talk about music and stuffs...

As for your questions, I think Joseph has answered them... the only thing I can add is to stock lots of resistors and try to match them well and get as close as possible to the given resistance for the desired attenuation... Don't be afraid to series/parallel resistors or caps to get to the value...

Next time you are in town, I will have the 755C in OB ready and your welcome again to have a listening session, it may not ba as horny ...

Arnold,

Sorry, for being a bit OT...

I'm glad you are having a nice experience with the OBs...

Regards,
Joel

[vintage_dog]

....Hi Francis,

Thanks for emailing me directly! I wouldn't have noticed the thread because I was practicing....anyway it looks like OB building season from around the world. During the holidays I received emails from quite a few OB builders here in the USA, S. America and Europe.

Answers:
.......JE

JE, thanks heaps for continuing to inspire us to take this (OB) route...

[ichabod]

Yes, can't thank JE enough as well as Arnold and Joel (SETUP2) for walking me through open baffles!

JE is the epitome of what Art Dudley has been suggesting all along to reviewers of audio gear. He (Dudley) says it should take about 50,000 hours of listening to both live and recorded music to get a good sense and perspective on what good audio should sound like.

JE has that enormous experience as a musician, and blends this quite perfectly with the "right" stuff to sound like the music he plays. The OBs are a testament to his awesome talent as a musician, and a gearhead all rolled into one!

I hope JE can do another concert in Manila for Wiredstate Francis. There's enough membership at WS to help promote such I believe.