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View Full Version : Using 808-8As or 8Bs in Altec Valenica's



diamondsouled
10-06-2007, 08:38 PM
Hi,

Just wondering if it is worthwhile to change out the original horn driver in the Altec Valencia's for an 808-8A or 8B? The higher power handling of the 808's would come in handy.

Larry

CONVERGENCE
10-06-2007, 09:40 PM
I would choose the 808-B over the 808-A . The B uses the Tangerine phase plug which refines the technology of proper phasing,ensuing maximum high frequency reproduction while maintaining smooth overall response. The 808 series uses a symbiotic diaphragm .The 806 is an earlier model . GPA can replace the Symbiotic with newer better diaphragm.

.............

RKLee
10-06-2007, 10:38 PM
Ditto on CONVERGENCE reply. I had a 806-8B, and there is just not enough high end with the symbiotic diaphragm. I added an EV T350. I liked the symbiotic diaphragm because it can handle a tremendous amount of power, but to me the hi-frequency response falls off appreciable around 10kHz.

diamondsouled
10-06-2007, 11:08 PM
The Tangerine was introduced in 1978 correct?

I'm fairly sure that the drivers in my early seventies Valencia's are 806-8As.

So the 808-8B was basically a professional version of the 802-8G?

I'm not sure how much difference in sound there would be switching the 806-8As for the 808-8Bs.

I'm using JBL Baby Cheeks above 6000 Hz with my Valencia's and like the sound. I plan on biamping them though so having the extra 20 watts handling capacity would be good.

I'm wondering, would the midrange be improved using the 808-8B?

By the way I have the original spec sheet for the Valencia as well as two Altec catalogs and some price lists that aren't on the Lansing Heritage Site yet. Who would I contact to give scans to for uploading?

Thanks

Larry Rowe

4313B
10-07-2007, 04:53 AM
Who would I contact to give scans to for uploading?Don McRitchie (http://audioheritage.org/vbulletin/member.php?u=1)

Russellc
10-07-2007, 06:26 AM
Hi,

Just wondering if it is worthwhile to change out the original horn driver in the Altec Valencia's for an 808-8A or 8B? The higher power handling of the 808's would come in handy.

Larry
The difference has already been stated by posters above. You will get the tangerine phase plug with the 808 8B. The 808 8A does not have this type of phase plug.

The "increased power" capability comes from the fact that the 808 8B comes originally with the symbiotic diaphragm and the use of a "loading" cap. This is not a capacitor, but a plastic dome like contraption that nestles in behind the actual diaphrams dome. both of these devices subtract from "high fidelity" use in the home, but add power handling for the PA type use. The symbiotic is no longer available. If you want this higher power diaphram, you must go th GPA, I believe they offer the Pascalite diaphram, which is said to sound good and have increased power handling.

I myself use the 808 8B, with removed loading cap, (which necessitates the use of slightly shorter screws, and a felt in the back of the cover...both available from GPA) and replaced the symbiotic with the GPA aluminum diaphragm. This is exactly like the 802 8G now, and I consider it the better 1 inch Altec driver, you may not.

Russellc

Russellc
10-07-2007, 06:33 AM
I would choose the 808-B over the 808-A . The B uses the Tangerine phase plug which refines the technology of proper phasing,ensuing maximum high frequency reproduction while maintaining smooth overall response. The 808 series uses a symbiotic diaphragm .The 806 is an earlier model . GPA can replace the Symbiotic with newer better diaphragm.

.............

I may be incorrect here, but I also am under the impression that the 806 uses a slightly smaller (shorter) magnet as well?

Russellc

CONVERGENCE
10-07-2007, 08:34 AM
I may be incorrect here, but I also am under the impression that the 806 uses a slightly smaller (shorter) magnet as well?

Russellc

The specs for the 804,807 show a Flux density of 13000 Gauss. I would presume that the 806 had a 13000 Gauss density also as oppose to the 15250 Gauss for 808 and 802.

...................................

diamondsouled
10-07-2007, 01:51 PM
Thanks all,

So the 808-8B and the 802-8G are the same driver? Besides the modification to the 808-8B to make it higher power handling?

As for replacement diaphrams I've heard that there are titanium as well as aluminum ones available.

These ones on eBay are?

http://cgi.ebay.ca/Diaphragm-for-Altec-604-802-807-808-8-ohm-NEW-P-10-908_W0QQitemZ190157943056QQihZ009QQcategoryZ47092Q QtcZphotoQQcmdZViewItem

Would there be any appreciable difference in midrange using the 802-8G over the stock 806-8A?

Thanks

Larry

CONVERGENCE
10-07-2007, 02:03 PM
Thanks all,

So the 808-8B and the 802-8G are the same driver? Besides the modification to the 808-8B to make it higher power handling?

As for replacement diaphrams I've heard that there are titanium as well as aluminum ones available.

These ones on eBay are?

http://cgi.ebay.ca/Diaphragm-for-Altec-604-802-807-808-8-ohm-NEW-P-10-908_W0QQitemZ190157943056QQihZ009QQcategoryZ47092Q QtcZphotoQQcmdZViewItem

Would there be any appreciable difference in midrange using the 802-8G over the stock 806-8A?

Thanks

Larry

Sorry can't help on that one. I used new A-7 500, A-5X, A-8, 604(612) in the early to late 70's.

.........

diamondsouled
10-07-2007, 02:40 PM
Thanks Conv,

Your reference to A7's made me think of this pic from the 70's of a wall of A7's in a studio. Wouldn't want to be standing under them in a .8 on the richter scale.

Lar

garyl
10-07-2007, 05:09 PM
Sounds as though there is some confussion here so lets try again.

808-8A has a circumferential metal phase plug and came with a symbiotic diaphragm and loading cap.

I am pretty sure the 808-8B came with all the same except that it had the Tangerine (Tangential) orange phase plug. Both appear to be the identical motor and also identicle to the 802-8G models.

On both the 808s you can do away with the loading caps and symbiotic frams and add the felt to the rear covers and use aluminum frams from GPA or other sources for home fidelity purposes. The loading caps is where the higher power capabilities come from!

I have all three, 802G, and 808 A&B and all with the same GPA 34647 diaphragm and can't hear a bit of difference between them.

I can attest they all sound best when run through the model 19 XO at 1200Khz with the Zobel filtering. Just changing the driver on the Velencia from an 806 to an 802/808 and not doing any updating to the XO will probably be a wasted effort IMO.
I am also not too sure there is an audible difference between tangential and circumferential phase plugs! Altec marketed them as a big step forward but I am more inclined to believe they were more of a cost saving at the time, Molded plastic Vs machined metal. I would be interested in seeing some graphs of both 808-8A and 808-8B with identicle frams and rear cover felts and suspect there really wouldn't be much difference at all!

Gary

diamondsouled
10-07-2007, 06:56 PM
No confusion Gary,

Thanks for the info. Interesting how they got more power handling out of the 808-8B through adding the loading cap.

Larry

Zilch
10-08-2007, 01:06 AM
The curves you seek for 802 and 806 (and others) are in this thread:

http://audioheritage.org/vbulletin/showthread.php?t=14690

I know, it's a chore to wade through it, as I have not done the index I promised, but I and many others put a lot of time and effort into figuring out Valencias there, as, apparently, no one had previously done.

Bottom line, you're going nowhere worthwhile with Valencia without upgrading to Model 19 network, or similar, as Gary says. See also Speakerdave's synthesis of the situation here:

http://audioheritage.org/vbulletin/showthread.php?p=187098#post187098

As you'll see in that thread, there are suitable alternatives to Altec compression drivers, as well.... :yes:

diamondsouled
10-08-2007, 02:14 AM
Hi Ziltch,

I do plan on upgrading the crossover, most likely putting a new three-way one together. Is the schematic for the Model19 crossover available somewhere?

I'm already using JBL Baby Cheeks with my Valencia's crossed over at 6000 Hz. so the sound is already far better than stock. I used 077's with an earlier pair of Valencia's I put together myself back in 75 and the sound was great. I used my JBL 418B guitar speakers in them lol.

I use tube amps to power these and to my ears they sound quite good. I have bypassed the crossover caps with PIOs though.

I also own a pair of the old ESS AMT-1A Monitors, as well as 4 extra sets of the Heil Transformers that I plan on using with some dipole woofer projects I have on the back burner.

Thanks for the links by the way.

I know a lot of people have written off the old horn speaker designs since the Thiele-Small parameters changed the direction of speaker design in the mid-seventies. Thing is a good percentage of the music that was recorded between 1930 and 1980 was monitored in the studio on such horn speakers so they do reproduce what the musicians, engineers, and producers were hearing when recording, mixing, and mastering. Whether that is good or bad is more a matter of taste than any absolutes; just as it is with hi-end capacitors and NOS tubes in tube gear.

To tell the truth though I wouldn't have a set of Valencias without 077s, 2404s, or an EV equivalent. The 811-806 combination just doesn't do from 800Hz to 20,000Hz justice. Not too surprising though when you cross them over at 6000 Hz as well it improves the 800Hz - 6000Hz, far less IM distortion, better dynamics.

Lar

garyl
10-08-2007, 06:36 AM
Yes Zilch, the info is in the thread but we never did any testing like I am asking about.

The 802-8G, 808-8A and 808-8B all have the same motors with the one exception being the 808-8A has the circumferential metal phase plug while the 802-8G and 808-8B have tangerines.

It would have been nice, while we were at it, to see if the phase plugs really made much difference at all. :banghead: I could have sent a pair of the 8As at the time but just figured you had enough on the plate with all the various drivers you were testing.

I am not sure about the function of the loading caps but it sure looks to me like they allow for higher power handeling by protecting the diaphragm from overextension. Kind of like a backer plate right behind the dome keeping it from going too far. When you remove the cap and add the felt to the rear of the cover it sounds a bit smoother yet leaves the diaphragm unprotected from behind if you overpower it.

I have seen the tiny flat wire leads both broken (NOT BURNED AT ALL) from what I suspect is too much extension and burned right off from what I expect is too much power.
The new GPA frams have the leads routed different and they appear to be stronger and with no 90 degree bend.

Gary

spkrman57
10-08-2007, 09:43 AM
802 - aluminum diaphram
808 - same driver w/symbiotik diaphram

806 - aluminum diaphram - smaller magnet version of 802 w/2db less effeciency
807 - same driver w/symbiotik diaphram

Later 800 series and most 900 series(800 - alnico/900 - ferrite magnet) had "tangerine" phase plug. Earlier units have "circumferential" phase plug.

Ron

Zilch
10-08-2007, 12:01 PM
It would have been nice, while we were at it, to see if the phase plugs really made much difference at all. :banghead: I could have sent a pair of the 8As at the time but just figured you had enough on the plate with all the various drivers you were testing.I forget what all I had here now, actually. :p

In any case, it was obvious to me that the tangerine phase plug majorly advanced HF extension over the earlier Altec annulars. I also found, for what reason I never determined, that the old "equivalent" JBL LE85s with original aluminum diaphragms did a better job than either of them, both in extension and uniformity, at least insofar as the measurements were concerned.... :dont-know

diamondsouled
10-08-2007, 03:33 PM
I forget what all I had here now, actually. :p

In any case, it was obvious to me that the tangerine phase plug majorly advanced HF extension over the earlier Altec annulars. I also found, for what reason I never determined, that the old "equivalent" JBL LE85s with original aluminum diaphragms did a better job than either of them, both in extension and uniformity, at least insofar as the measurements were concerned.... :dont-know

This was with the JBL lense correct?

Lar

Zilch
10-08-2007, 04:14 PM
This was with the JBL lense correct?

LarNo. I clamped the JBL drivers to the Altec horns for testing. They're not my horns, and I had no authorization to drill the requisite additional mounting holes in the flanges.

Results are in the Valencia thread, as is the M19 schematic you're looking for.... :yes:

diamondsouled
10-08-2007, 07:26 PM
Results are in the Valencia thread, as is the M19 schematic you're looking for.... :yes:[/quote]

Thanks Zitch!! I didn't look through all the posts in that thread yet.

Larry

diamondsouled
10-08-2007, 10:06 PM
Whoa that's a long thread!!!

Took me a couple hours to get to the Model 19 Network, lol!!!

Course I was reading all the interesting stuff about the Valencia and Model 19 drivers and horns.

I still have to read from page 25 on, tomorrow.

Thanks again Ziltch

Larry

garyl
10-09-2007, 06:25 AM
I forget what all I had here now, actually. :p

In any case, it was obvious to me that the tangerine phase plug majorly advanced HF extension over the earlier Altec annulars. I also found, for what reason I never determined, that the old "equivalent" JBL LE85s with original aluminum diaphragms did a better job than either of them, both in extension and uniformity, at least insofar as the measurements were concerned.... :dont-know

LOL, I have no idea how you got half of the testing done with all you had on that plate Zilch!

To recap what I remember of it, You had Altec 811B Velencia horns and a few Altec 806 Velencia drivers with Velencia XOs both stock and with upgrades.

I sent a pair of Altec 802-8Gs fresh from GPA after recharge and new frams. Another friend sent a pair of stock 802-8Gs with alnicos flux unknown.

You also had a number of other non altec drivers. BMS 4550 and 4552 shined the brightest!

My 802-8Gs did OK but fell off pretty fast after around 12-14K.

The only comparison we seemed to have missed is in checking the response of Identicle drivers and diaphragms but one having the tangerine, 802-8G and the 808-8A having the metal phase plug.

I just don't believe the tangerine phase plug does all that much and it would have been nice to find out if the hype is fact or fiction.

At the auctions you can buy the 808 with metal phase plug for about half the price as the identicle driver with the tangerine! You already proved the BMS does a fine job and can be had for less!

Here is an 808 and 802, identicle in every way except for the plugs.


http://img.photobucket.com/albums/v722/Gamalot/HF%20Drivers/Set58_01-1.jpg

http://img.photobucket.com/albums/v722/Gamalot/HF%20Drivers/32_1.jpg

Gary

diamondsouled
10-09-2007, 08:34 AM
Hi Gary,

Was the same phase plug used in all 808-8A's because the picture used in the spec sheet for the 808-8A doesn't seem to correspond to your photo of the plug with the three crescent slots.

Zilch
10-09-2007, 12:33 PM
Was the same phase plug used in all 808-8A's because the picture used in the spec sheet for the 808-8A doesn't seem to correspond to your photo of the plug with the three crescent slots.Yes it does. The three crescent slots comprise the innermost of two concentric "rings" shown in cross section in the brochure.... :yes:

diamondsouled
10-09-2007, 07:29 PM
Thanks Ziltch,

Kind of hard to picture from the side view cutaway, lol.

Read through the 57 page 850 odd post thread, lots of good info!

Lar

Zilch
10-09-2007, 08:39 PM
Read through the 57 page 850 odd post thread, lots of good info!You can tell we had a bunch of fun doing it. :D

Some rainy weekend, I'll do the index.... :yes:

SMKSoundPro
10-09-2007, 11:22 PM
I am SO thrilled that what was accomplished by the Val thread is of some use to others!

The BMS fix was smooth, and was thrilling to hear. The ZilchLencia's were alot of fun for Lisa and I to experiment with. It really did't cost too much and we know the old Vals were the better for it.

I have not heard too much from the original owner of the vals, but I am sure they will turn up again, here in Anchorage. That somebody will find my name inside and call. Its happened before.

If they fell back in my lap, I would keep them. They were Keepers!

All that being said though, I really like my L200b's with the double 2245-18's subs underneath! I still need to add the 2405 slots. I was kind of thinking to add a small enclosured 2123 10" in the middle (like Miss Heather's) and then triamp the whole deal. It really sounds good up here!

Good luck with your Altec Valencia adventure. The only thing that I did not get a chance to do was to stiffen the box. I wanted to put a brace in from baffle to back. The box sure vibrated, alot.

Hope all is well with everyone.

Thanks.

Scott.

diamondsouled
10-10-2007, 02:50 PM
Hi Scott, Ziltch, and all,

Not only useful but like a good page turning novel.

Is it my imagination but is the consensus here that the 2405-077 is superior to the 2404 baby cheeks?

Having not had a pair of 077s around for a long time it seemed to me on first listening to the baby cheeks that they were quite similar but perhaps a little less directional than the 077s. The 077's are a lot rarer than baby cheeks, sooo.

They are basically the same driver with a different lense though, correct?

Lar

Zilch
10-10-2007, 03:24 PM
Yes, and a substantially different dispersion pattern as result....

diamondsouled
10-10-2007, 05:05 PM
"Yes, and a substantially different dispersion pattern as result"

Guess I'm going to have to keep an eye out for some 077s so I can do an A/B.

How about the 077s compared to their newer version the 2405? Which is superior?

Also I don't remember you're saying Ziltch if you preferred the BMS 4550 or the 4552. I'm giving some serious thought about trying out a pair in my Valencia's.

Thanks

Lar

Zilch
10-10-2007, 06:01 PM
077 and 2405 are the same, performance-wise.

I prefer the BMS 4552 to 4550; I believe I can hear a difference, more clarity in the upper midrange, but the difference is subtle. Is it worth $30 apiece more? :dont-know

diamondsouled
10-10-2007, 06:57 PM
Still, for under $150 ea. the 4552 is a good deal. German's design and manufacture quality equipment in my experience. I have a Uher Royal Deluxe RTR that is over 30 years old and it is still going strong.

I can't remember, did you put together a new design for a complete network to use with the Valencias and the BMS drivers or did you do a redesign of the original and or the Model19?

Lar

Zilch
10-10-2007, 07:45 PM
It's a simple compensation network added on after the Valencia crossover, documented in the thread. That was my assignment. I also used the BMS with the M19 crossover, and that worked, too, though the control settings were different.

Others are working on more comprehensive filter redesigns for Valencia and similarly configured Altec two-ways.

It's a slightly different network for 846A (16 Ohms) versus 846B (8 Ohms), and you must order the correct impedance BMS drivers.

Just using the BMS with the stock crossover alone is itself an improvement with respect to HF extension, but the midrange is still too "forward."

The point of using the BMS is not to have to add a tweeter, which has its own set of problems, as documented in the thread....

jackgiff
10-10-2007, 08:21 PM
Also I don't remember you're saying Ziltch if you preferred the BMS 4550 or the 4552. I'm giving some serious thought about trying out a pair in my Valencia's.

Thanks

Lar

Hi Lar.

I ended up with two pairs of Valencias, each of which has a pair of the two BMS drivers mentioned. Zilch can hear a difference, but I really can't. However, either pair is totally different than standard, and much improved and I sold the two pairs of 806A's for more than the cost of the BMS drivers. No going back for this kid.

diamondsouled
10-10-2007, 08:44 PM
Hi Jack, thanks Ziltch,

Ziltch: Where will the more comprehensive filter redesigns be posted when they're done? Will they be for use with the BMS drivers?

Jack: I was thinking a person could probably get more for their used 806-A's than the cost of the new BMS drivers. Sounds funny but it's true. Where did you pick up your RTA up at? Been thinking it's about time I got one.

Thanks

Lar

Zilch
10-10-2007, 08:52 PM
Ziltch: Where will the more comprehensive filter redesigns be posted when they're done? Will they be for use with the BMS drivers?Yes, BMS drivers on 811B horns. I will encourage them to post their work here, but I believe they've already said they would.... :yes:

Hi, Jack! :thmbsup:

SMKSoundPro
10-10-2007, 10:38 PM
Hi Jack, ditto!:wave:

Scotty.

Lars: Remember to keep it simple.

jackgiff
10-11-2007, 05:18 PM
Hi Jack, thanks Ziltch,

Jack: I was thinking a person could probably get more for their used 806-A's than the cost of the new BMS drivers. Sounds funny but it's true. Where did you pick up your RTA up at? Been thinking it's about time I got one.

Thanks

Lar

I bought mine from an E-Bay dealer somewhere in the South. Can't remember their name, but they are available pretty much everywhere. Measuring things really makes developing a speaker more exciting. I built a pair of speakers for some friends a few years ago which use Trusonic 120FR's and tweeters. I bought crossovers from Parts express which were high pass 5 KHz only. They sounded damn good at the time. Now that I have the ability to measure response, I borrowed them back for a week while Ben and Jane were in Mexico. Seems the tweeters needed to be reversed, and the woofers needed a cutoff at 5 Khz as well. After they got home, they can't believe the difference in sound. Now they sound like they should have originally. It really makes a big difference being able to measure things, as well as just listening to them. I wouldn't want to build another pair without being able to measure their response. Some people can tell just by listening, but even though the ones I built were so close, they are now just supreme. I would hate to give up my RTA.

Hi Zilch and Scott. Good to hear from you both again. Can't wait till the next thread about developing some great sound.

garyl
10-11-2007, 07:23 PM
One question I have always had for those with the equipment to do all the testing. Does it ever stop?

By this I mean, can you ever really be satisfied that a particular speaker is just "Good Enough" and be happy with what you did and how it sounds?

I have friends who are complete gear heads and think nothing of spending thousands to get another few HP out of an engine that is already producing way more then ever intended. Other friends who are complete geeks who tweek their computers to break neck speeds and capacities no normal individual could ever need.

Am I wrong to think the test equipment is capeable of telling 99% of us what our ears can't even come close to hearing?????

I have this vision of the mad scientist never ever being happy until he finds absolute perfection by some unrealistic standard!

Please don't get me wrong here. It is great to know your equipment is performing properly yet I can still be quite happy if my speakers sound pretty good to me.

From what is advertised, shouldn't we all just have Bose? :D

Gary

diamondsouled
10-11-2007, 07:42 PM
Speaking for myself I think that I would only use an RTA if I was wanting to confirm what my ears tell me, or if I was setting up Pro Gear in a variety of venues. A loud speaker management unit would come in real handy in that case. If I were to buy an RTA or loud speaker management unit and use it at home I would check to see if I had things phased and time aligned properly. Like Jack noted it was only when he checked the speakers that he had built for his friend that he caught the fact that the tweeter were out of phase.

If a person was putting together many DIY speakers and crossovers projects this sort of RTA unit would soon become indispensible.

Lar

hjames
10-12-2007, 03:52 AM
I bought mine from an E-Bay dealer somewhere in the South. Can't remember their name, but they are available pretty much everywhere. Measuring things really makes developing a speaker more exciting.

I wouldn't want to build another pair without being able to measure their response. Some people can tell just by listening, but even though the ones I built were so close, they are now just supreme. I would hate to give up my RTA.


Can you give us specifics about what RTA you got?
What features convinced you that was the one to get?
(Seems to be a lot of possibilities when looking at that field)

Thanks Jack!

4313B
10-12-2007, 07:38 AM
One question I have always had for those with the equipment to do all the testing. Does it ever stop?Not for some people. It seems to be kind of an addiction like anything else. I suppose eventually they will burn out and find something else to obsess over but who knows. If they receive positive encouragement to continue their addiction then there probably isn't an end in sight.
By this I mean, can you ever really be satisfied that a particular speaker is just "Good Enough" and be happy with what you did and how it sounds?From observation I don't really think that is what they are after. It's more the thrill of running curves and blogging than actually coming up with a fully functional loudspeaker system that will appeal to alot of people. If there wasn't a forum for them to interact with they would most likely find something else to do with their day.
I have friends who are complete gear heads and think nothing of spending thousands to get another few HP out of an engine that is already producing way more then ever intended. Other friends who are complete geeks who tweek their computers to break neck speeds and capacities no normal individual could ever need.Right, meanwhile you just use your car or computer as another tool in your life without the obsessive behavior. We all have to fill our days somehow. Some people like to run curve after curve and blog about it. It takes all kinds to fill the freeways. I certainly put a few years in trying to squeeze every last get up and go out of small and big block Chevy's simply because it was fun. Then I realized what a waste of time and money it was and moved on.
Am I wrong to think the test equipment is capeable of telling 99% of us what our ears can't even come close to hearing?????We have a few forum members who are well versed in measurements - They are professionals. Perhaps they can post about proper measurement techniques and why we do it if they have the time and are so inclined.
I have this vision of the mad scientist never ever being happy until he finds absolute perfection by some unrealistic standard!Some DIY folks seem that way. I wouldn't let it bother me if I were you.

Some of the professional guys who design and build the best loudspeaker systems are actually quite normal and are definitely aware of their own "successes" and "failures" with respect to various system designs. They are thoroughly aware of the product lifecycle from start to finish. Some have designed systems that many people really liked but that they personally didn't like at all. Go figure.
I can still be quite happy if my speakers sound pretty good to me.That is the end goal of most people. They buy what they prefer and they end up being content with their decision.
From what is advertised, shouldn't we all just have Bose? :DI would say that's probably true for most people.

garyl
10-12-2007, 08:06 AM
:rotfl::rotfl::rotfl: