Altec owner's upgrades, mods, short-cuts, etc.

Discussion in 'Audio Hardware' started by KT88, Oct 9, 2019.

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  1. KT88

    KT88 Senior Member Thread Starter

    Hi Guys,
    I have really stepped in it now. I accidentally bought a bunch of old Altec gear. Basically, I have a couple of incomplete VOTT speakers. I have some parts that I will be selling or perhaps trading, but I also will be buying some more parts. Since I can't quite get a complete speaker system assembled from what I have, and I don't want to get further invested into it all, I will be looking for a couple of HF drivers to complete one pair for now. Then I will sell the left over parts from the second pair as they take up WAY too much space.

    I also have an unfinished Tannoy project that I may use a couple of LF drivers with, if and whenever I find time and space for that. For now, my dilemma is to choose a matching pair of HF drivers for these Altecs. I have the 511B horns, and one 808-8A driver, which needs a diaphragm. So I either source another 808-8A and a pair of diaphragms or I choose a pair of other drivers. The least expensive route is to use other drivers as there are many options. What have owners here found to be good, affordable solutions?

    Please feel free to chime in with any other tweaks not related to the HF units as there are always many hurdles to jump with vintage speakers like this.
    -Bill
     
  2. BIGGER Dave

    BIGGER Dave Forum Resident

    You probably are already familiar with this vendor, but if not, they offer lots of options for vintage Altec and JBL owners:

    Home - Great Plains Audio
     
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  3. SandAndGlass

    SandAndGlass Twilight Forum Resident

    Bill, I had 808-8A drivers on my original pair of A7's from the early 1970's, they are very nice sounding drivers and have the Altec Symbiotic diaphragms in them, which I find to be natural sounding. Since my original A7's were custom built, I also had the 511B sectoral horn, but had the N801-8A, 800-Hz. frequency dividing networks (Altec's term for 2-way crossovers).

    I lent my speakers to a local playhouse for a local production of Funny Girl, just to be used for the vocals, as the house P.A. system was used for the orchestra. A local girl, who went by the stage name of Donna Page (her real name being Donna Paige Helmintoller), played the lead character, Fanny Brice.

    Donna changed her stage name to Paige O'Hara, and went on to star in Showboat on Broadway and played in Oklahoma and South Pacific. She joined the Broadway production of Les Misérables, where she played the role of Fantine.

    She is probably best known for paying the part of Belle, in Walt Disney's animated version of Beauty and the Beast.

    I tell you this, because the A7's with their 808-8A drivers and the 511B horns were absolutely stunning with Paige's vocals.

    A couple of things...

    First, even though the 808-8A series driver's are designed to be used with the Altec 800-Hz. crossovers, they can also be used down to 500-Hz. with Altec's 500-Hz. (N501-8A) crossovers and are rated at 30-Watts (which is more power on the HF horns then you will ever use).

    Altec will tell you that their frequency response is from 500-Hz. up to 20-kHz., (spec sheet here).

    I will tell you that they lie and that the drivers with the Symbiotic diaphragms will begin to roll off above 10-kHz., not that that necessarily matters, as they are a fine 2-way speaker and excel in the midrange, where vocals live.

    My main pair of A7's have the 908 series driver, which is the higher powered driver and also has the Symbiotic diaphragms. I also have another custom pair of A7's with their lower powered 902-series driver, which is supposed to be the technically better of the two, having an aluminum diaphragm. The aluminum diaphragm is supposed to be flat, all the way through 20-kHz.

    I don't care for it as much and don't feel that it has the natural sound that the Symbiotic drivers have, sounding more metallic to me.

    I also never cared for the Altec crossovers, back in my teens. The problem is not that they don't effectively cross over at 500-Hz. or 800-Hz., depending on the model.

    The problem is, that they use a variable potentiometer to control the level of high frequency attenuation. In a home audio environment, if you want to HF horns to be correctly balanced with the bass driver, you need to decrease the amount of power that is going to the HF horn, which you do by turning down the frequency attenuation potentiometer.

    The upside of doing this, is that you end up with a correct balance between the LF and the HF.

    The downside of this, is that as you turn up the amount of attenuation, the sound emanating from the HF horn becomes dull and lifeless.

    In theater and P.A. applications, the attenuation control is usually set at zero, so this issue is not brought into play.

    The models that are used for playback in recording studios, accomplish this by using a less powerful magnet in the driver, thereby reducing the magnetic field on the voice coil and therefore making the HF horn not as loud. Photo is from an older Altec catalogue.

    [​IMG]

    In home use, I wouldn't recommend Altec crossovers...

    These are custom A7's which were specifically built for conductor Leopold Stokowski.

    The full article is available at Jeff's Place, Jeff Day being a very experienced authority on Altec speakers and their restoration. Jeff owns these speakers.

    [​IMG]

    F.Y.I. These are very large cabinets, larger than they appear in the above photo.

    [​IMG]

    Of course, conventional A7's are not always large enough for everyone...

    [​IMG]

    One of our member's, @Ezd also have a pair of A7's, which are the model A7-500-W, the Magnificent Voice Of The Theater speakers.

    [​IMG]

    The possibilities are endless...
     
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  4. Ezd

    Ezd Forum Resident

    I am sure I am repeating things you are already aware of, but this is what I have noticed when researching Vintage Altecs on the internet.
    • There is almost universal agreement to upgrade the crossovers, but that is where the agreement ends. Choices include a different designed passive crossover, active crossovers and a few owners prefer simply the same design with ugraded capacitors.
    • Some people believe the sound improves (less ringing) when some type of material is placed around the horn.
    • Some original cabinet designs can be improved by additional bracing and adhesive/caulk if the owner is not concerned about keeping everything stock.
    • Internal wiring may need updated.
    While myself and many others think vintage Altecs are reference quality speakers, the components are plentiful and not that expensive to purchase on the internet...

    Since you are in the audio business, you have a better understanding of what customers are willing to purchase and the sell price then most of us... Because you are not planning on keeping the speakers, I would advise anyone else who was asking those questions to simply sell the components they currently own as opposed to purchasing more components, assembling a pair of speakers, selling them and then selling the remaining components... You did not mention if you have existing cabinets or are building some new ones?

    On a side note, the link provided to Jeff's Place by @SandAndGlass provides some enjoyable reading and futher highlights how varying opinions are regarding the best sounding speakers... Jeff bought and sold a pair of Harbeth Super HL5, Harbeth 40.1's, owns a pair of Tannoy Westminster Royal SE's he bought new($35,000 in 2010) and has stated the Altecs pictured are at least as good as the Tannoy's after having the crossovers updated. He also owns two additional pairs of vintage Altecs.
    The Altecs pictured have a larger than stock cabinet, but the same woofer and horn/ driver are found in Altecs on craigslist for less then $1500-$2000.
     
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  5. KT88

    KT88 Senior Member Thread Starter

    I am not exactly sure what you mean by that. I am assuming that you are unaware of how complete the sets are. I do have 4 cabinets, 4 woofers, 4 horns, 4 crossovers. The trouble spot is that I have only one original horn driver and it needs a diaphragm.

    The dilemma being whether to buy a dud horn driver to match and replace both diaphragms to match, or buy some alternative drivers. The 808 is expensive when found working, and even duds are hard to find. eBay can be ridiculous price-wise when you just need a part to restore something. What I have already done is to buy a pair of cheap, but adequate replacement drivers. So I can finish one pair, no problem but they won't sell for as much as an original pair. The thing I would like to do next is to find a spare original driver and refresh a pair to original spec and aesthetic. The trouble there is simply cost. I am guessing that was also why you suggested just selling the components. I am also thinking of just selling one pair of components and one completed speaker system pair with the cheaper drivers. The proceeds from the components on the second set will cover costs for restoration of the other. If I could fetch a bit more for the original restoration, then maybe I'll go forward there. It'll likely cost an additional $150 - $200. The lower that I can keep the cost, the lower my selling price will be for the pair and likely the faster that I can sell them. I plan on letting a pair hang out for a little while for listening fun, so there is the real reason that I am tempted to go the original restoration route. I had a pair of the A7 speakers many years ago. These have the 1204B cabs as seen in the foreground of the photo below.
    [​IMG]
    -Bill
     
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  6. Ezd

    Ezd Forum Resident

    Bill,

    I did a poor job of wording that my personal observation is vintage Altec components are a buyers market, price relative to quality, unlike most high-end audio... I could not tell from your original post if in addition to repairing/replacing the drivers, you had existing cabinets or also planned on building the cabinets... To directly answer the question of how to proceed, one option would be this pair of 808-8A drivers for $425 or best offer on ebay.
    vtg pair altec lansing 808-8A original symbiotik driver speaker horn tweeter | eBay

    The reason I would advice people to not build/restore and sell a pair of VOTT is I doubt there is any profit in it .... I would highly encourage anyone to build/restore and keep for themselves a pair of VOTT or any vintage horn speaker.

    The point I tried to convey was because you sell/repair audio for a living, you would know better then most of us if a pair of VOTT''s could be assembled and a profit made... To those of us not as familiar with pricing, I was guessing it would be hard to make any profit by assembling them and it would be easiest to just sell the components they already own as is.

    Currently for sale near me...
    1203a's for $800
    9844's for $950
    Valencia's for $1060
    Valencia's for 1500
    605's for $1600
    The cabinets for the above need work, but the components seem good.

    Individual drivers can be found on the internet for high-prices, but frequently those same drivers can be found inside of cabinets in need of work on local craigslist for much less. Analogous to parting out a local vintage stereo console for the high-quality amplifier inside, which then sales on ebay for much more than the complete console cost prior to being parted out.
     
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  7. KT88

    KT88 Senior Member Thread Starter

    OK, I was hearing the it's not worth it commentary, but couldn't decide how you arrived at t. Since I do have cabinets, it's easy enough to get one set going using the more cost effective drivers. $400 adder isn't gonna happen. I saw those prices myself. My concern is $150-$250 more to offer an original set vs one with aftermarket HF drivers.

    If I sell the original 808 driver, then I am selling all of the other components, the horns and x-overs associated with it as well. The cabinets by themselves probably have little value. Lots of people fancy having the 511 horns for projects I am sure. The finished systems sound better than La Scala speakers IMO.

    Your ideas agree with my thoughts and experience. I just hate to sell the 808 when I have maybe some hope of finding another for a decent price and keeping the system together. Parting it out seems a shame, but it is also what I was thinking would have to happen to the second pair, just to make the ends meet financially. I think I need to visit the Altec forum and see what the interest is in any trades or to source a driver. It is more profitable to just sell the parts, but it's not as much fun as restoring a pair of classics! Damn!
    -Bill
     
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  8. Ezd

    Ezd Forum Resident

    The situation kind of reminds me of vintage automobiles... There are some 1950's and 1960's cars, a person could purchase one in rough condition (if you can find one), do a thorough restoration and make a nice profit. However, if a person did a thorough restoration on most cars of that era, it is difficult to even break even, let alone make a profit. On the latter example, it would only be worth doing a restoration if that particular car was one the individual wanted to keep for themself, and the goal was not selling for a profit.
    The economics of supply and demand...
     
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  9. KT88

    KT88 Senior Member Thread Starter

    Yeah, there's not a lot of money in it at all. And it's a huge PITA as far as moving and storing them. It's definitely just a thing you have to be passionate about. It's the same way with the vinyl record sales operation here. Very little money made and it's hugely time consuming. But hey, people have a local record shop. Some things you just do because you know that they should be done.
    :cheers:
    -Bill
     
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  10. onlysleeping

    onlysleeping Forum Resident

    Location:
    Chico CA, USA
    I have a set similar to @Ezd , the A7-500-W. They are quite large, and sound large. I consider them family heirlooms. My cabinets have a few dings and scratches, but still look good.

    There isn't much bottom or top end on these. Frequencies around 70hz roll off, and above 10 roll off. The nice thing is they aren't fatiguing to listen to for hours on end. They don't need much power to get loud.

    Compared to Klipschorns or Cornwalls, they may not be as exciting a listen. For their size, they don't make the house shake. Also they are 16ohm. My particular set has the N-500-G crossover, 802d horn, and 416a woofer. Paired with a Mcintosh 2505 on the 16ohm tap, they sound pretty good. On the 8ohm tap, they lose bass, and seem to need to be cranked up more on the preamp to get loud.

    As a side note, this is similar to a setup Howard Hughes had - Roger Tolces and Howard Hughes - Advanced Electronic Security Company

    I recently had the crossovers in mine rebuilt to spec by a local tech. It seemed to open up the high end a bit, but maybe at the cost of some bass. I'm also not 100% sure I wired everything back right. The crossover has a note stating "See speaker instructions sheet for correct phasing connections", but I have yet been able to find that instruction sheet online. If anyone has a copy, I'd appreciate having a scan! The back of my cabinets are labeled in pencil which side is positive and negative. The crossover shows a diagram, but the cables from the cabinet to the crossover are not the same on each speaker. I think I need to flip which is + and - per speaker, meaning on one speaker left terminal is negative, other speaker, left terminal is negative, but I'm not sure.

    I know Crites makes crossovers for Klipsch, but are there any recommendations for 'plug and play' crossovers for the Altecs?

    I think one major difference with the A7-500-W compared to standard A7, Khorns or Cornwalls is that they are fully sealed - there is no bass port. I think this is why they roll off so much in the low end. In my opinion, you really need a subwoofer to pair with the A7-500-W.

    I have read that swapping with a JBL woofer may make the bass stronger. I also read somewhere that rotating the woofers helps.
     
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  11. onlysleeping

    onlysleeping Forum Resident

    Location:
    Chico CA, USA
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  12. KT88

    KT88 Senior Member Thread Starter

    You need to be certain that both speakers wires from the amp to right and left speakers are wired the same way. Look at the crossovers and see what color wires go to which input terminals from the amp. Then be sure that each is done the same way. It is not as important which screw on each gets the positive lead, so long as both the left and right speaker are wired in exactly the same manner. That keeps the amp to speaker connection in-phase. Next, have a look at the output wires from the crossover to the drivers. Both woofers should also be connected the same way in each cabinet, to the same color wires. The same is true for the HF drivers. If you get one speaker (input to crossover) backwards from the other or one woofer connection from the crossover backwards from the other, you will lose a lot of bass output.
    Most of the Altec drivers that I have seen are marked for polarity with red and black terminals or markings. The old crossover box inputs are not marked however. They are simply described in the diagrams as terminals 1 and 2. Terminal 1 in the diagrams is positive. So I'd just take a stab and say that from left to right, they are 1 and 2, thus positive and negative. Again, that's not as critical as it is to simply ensure that both speakers are wired the same. Doing that keeps the speaker systems in relative phase and nets proper bass output. Then, you want to be sure that the drivers in each cab are wired the same way, for the same reason. The proper driver to crossover output wire color diagram should be printed right on the crossover. If you have questions, Great Plains Audio should have answers.
    Here are wiring diagrams and instructions. https://greatplainsaudio.com/wp-content/uploads/2017/07/Networks.1.pdf
    -Bill
     
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  13. Ezd

    Ezd Forum Resident

    The answer depends on the definition of "plug and play" and the model of Altec speaker... I personally have never seen an aftermarket crossover that is pre-made specifically for a stock A7 (I have seen some for Altec speakers that have added a super-tweeter)... Great Plains Audio offers crossovers for other Altec models and you earlier attached a link to a website where the owner will custom build Altec crossovers, custom built crossovers can be had from other sources as well... Forum member @SandAndGlass has had very good results with crossovers from ALK Engineering and recommends them.

    I agree and believe that most owners do add a subwoofer.
     
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  14. onlysleeping

    onlysleeping Forum Resident

    Location:
    Chico CA, USA
    Thanks! That is what I did, but I wasn't sure about the note on the crossover saying see instructions sheet for correct phasing. Prior to taking them apart, I took pictures of how everything was connected. I tried doing it both ways - connecting everything as it was, then connecting them as you suggested - both speakers the same. I used an online speaker phase test to make sure they were in phase.

    They have a good sound, but not the most exciting. Since they take up a lot of room, getting a sub is difficult in my space. And from living in other places, getting a sub that blends well is difficult.

    I have considered taking out the 'foam' insulation and replacing it with polyfil to see if it makes a difference.

    Hope I'm not threadjacking, just figured I wanted to mod mine too, so I'd tag in. Do you have any pictures of what you currently have? Are they the 'grey' cabinet? I think the bass port will make a big difference compared to the sealed version!
     
  15. SandAndGlass

    SandAndGlass Twilight Forum Resident

    [​IMG]

    Don't even bother. Even though Altec refers to the 1204B cabinet models as Voice of the Theater speakers they are not even close to what any of the A7's based speakers are with the 825 or 828 bass bins.

    These will never be A7's. No matter what you do or how much you spend, you will never get these to even approach the sound of A7's and they will never sound good in a home audio environment. The sound OK at best just as you see them in your photo.

    Parting them out is the best thing that you can do for your time and money.

    There are better modern sounding and less expensive speakers for P.A. applications, like those in the photo.

    There are unlimited inexpensive used P.A. speakers on eBay that are available for very little money.

    People are willing to pay good money for vintage Altec components.

    [​IMG]

    There is an A7 and there is not...
     
  16. SandAndGlass

    SandAndGlass Twilight Forum Resident

    K-horns are only right in the right environment. K-horns have one the the best bass cabinets ever designed but they require correct corner placement. A7's will never have the bass of a K-horn. However, Altec's sectoral horns and drivers are better than Klipsch product ever built.

    Cornwalls are nice sounding speakers and probably the best home audio of any of the vintage Klipsch speakers.

    They are not as exciting of a listen as your A7-500W's.

    They are theater speaker and are not designed to make the house shake, but to reproduce frequencies in the vocal range with clarity.

    Mostly a waste of time.

    Bob Crites is not a crossover engineer, he makes replacement crossovers for vintage Klipsch products, with upgraded components.

    This is an upgraded crossover from ALK engineering, which is designed for a vintage Klipsch La Scala speaker and crossover at 500-Hz.

    [​IMG]

    By adjusting the jumpers on the autoformer (the transformer looking thing on the left) you will be able to attenuate the power that is routed to the 511B horn in your A7-500W's. After doing this, you have better and more balanced bass.

    The ALK crossovers are used on my main pair of vintage A7's restored and upgraded cabinets. Which are now a 4-way system, with the addition of a JBL super-tweeter and a 15" passive commercial horn loaded bass speaker.

    [​IMG]

    You need a pair of ALK AP12-500 crossovers. A link to ALK's web site. The AP12-500 crossovers will run you $450/pr. plus shipping.

    [​IMG]

    All regular A7 cabinets roll off below 50-Hz. Typically, their -3 dB. point is about 47-Hz. And, yes you need a sub woofer.

    These are @Ezd's speakers, from the rear. I have also owned a pair of A7-500W's, some years back.

    [​IMG]

    Do not swap out your Alnico magnet with a JBL woofer. Do not "rotate" your woofer, leave it alone!

    With respect to Burwell & Sons Loudspeaker's, their "Mother of Burl speakers, shown below are $87,500 (without the optional subwoofer).

    [​IMG]

    No, leave the original lining alone.

    Leave your speakers completely alone, with the exception of replacing your crossovers, as explained above.

    And, add a sub!
     
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  17. onlysleeping

    onlysleeping Forum Resident

    Location:
    Chico CA, USA
    @SandAndGlass thank you! Wish I had known to ask about the crossover before having it rebuilt. I figured since they are 40 years old or so, they had to be out of spec.

    The altecs do sound great for vocals and movie dialog. A friend once commented she didn't need subtitles when watching stuff at my place, she could just hear it!

    I love the Altecs. Whenever I get a room large enough to have a decent sub paired with them, I'd do it. The slim profile dayton sub just doesn't cut it. Not compared to the Cornwalls.

    I like the ported Altecs a lot. They aren't the best looking things. Sound wise, they are hard to beat!
     
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  18. SandAndGlass

    SandAndGlass Twilight Forum Resident

    Which is fine. It is always good to have your original crossovers. Which is also why I also recommended you keep your Altec A7-500W's stock as they are a classic piece and should not be modified. Removing a stock crossover and placing a small board across the opening with a hole to run wires to an external ALK crossover won't change your speakers in any negative way. You can always replace the original crossovers anytime you wish.

    Rebuilding your crossovers with modern capacitors can somewhat improve their performance.

    Older electrolytic capacitors in power supplies will need replacing as will some non-electrolytic capacitors in amplifiers, which are subject to heat and high voltages.

    Mostly, capacitors in older speakers, which are non-electrolytic are usually fine, as they have never been subjected to heat or high voltages.

    Mostly, you are gaining better capacitors, when replacing your old ones with more modern caps. But, replacing any audio capacitors can also also alter the sound signature. Which is not always a desirable thing when dealing with vintage equipment that has a sound signature that is all its own.

    I put together a tour of my former audio room after my equipement listing. It might be of interest to you. It is descriptive text and photos of the room and audio gear.

    I have another pair that was customized by another individual and was encased in walnut cabinets. Shown without their front grills.

    [​IMG]

    He had the original crossovers rebuilt also.

    [​IMG]

    They are not even close to what the ALK crossovers are.
     
    Last edited: Oct 14, 2019
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  19. hammr7

    hammr7 Forum Resident

    What you do with the Altec gear you have depends so much on how you listen and what you listen to. I love the Altec sound, and believe you could do far worse (but not a lot better) if you try something else.

    I have Altec Malibus (806a/811b horns and pairs of 414z woofers) that I use as every day speakers. My musical interests are varied, but I don't need to push my Malibus anywhere near their power limits. The bass is fine for my purposes, since I don't need to shake down my house. I have abandoned the original N-800-F crossovers since they abandoned me, and stopped working correctly. I will eventually rebuild them, but the job is a bit messy.

    I have both passive and active 800 Hz crossovers and both work well. I have recently added a super tweeter (A Jensen RP-302) to compensate for the high frequency roll-off described above. I have the Jensen tweaked to cross over at ~ 11 kHz, and it is smooth to 20 kHz+, beyond my hearing and that of my son. As configured, at low to mid volume (the ranges I use) everything is clean and transparent. Bass gets a bit murky at higher volume, but that might be my ears.

    A comment or two discussed rotating woofers. I do it. The original high viscosity goop Altec put on their cloth surrounds tends to migrate down onto the cone (at top) and onto the baffle (at the bottom). It can eventually stick the surround to the baffle, at which point it affects sound and can damage the surround. The drip can occur in most any environment, although a warmer room can speed it up. The easiest way to counter this is to rotate the speakers 90 or 180 degrees every couple of years.
     
  20. SandAndGlass

    SandAndGlass Twilight Forum Resident

    I have all kinds of speakers, including the Altec's.

    Klipsch La Scala's and others...

    [​IMG]

    My main modified pair of A7's are the best speakers I have ever listened to (I have two other pair of A7's).

    I have owned different Altec's for close to a half century.

    In that room, I listen pretty much 24/7 and to many different genres of music.

    I don't doubt that there are many speakers out there that are better than the A7's but then they are also several orders of magnitude more expensive.

    Like those I pictured above from Burwell & Sons. Which are a lot nicer looking but I doubt that they really sound any better than my A7's.

    I have never had any issues with the "Altec goop" migrating into the cone area, but if someone wishes to rotate their speakers, I guess that it is OK, but I have never encountered this problem.

    [​IMG]

    It's not really about shaking the house. Member Charles Hidalgo posted this photo in the Klipsch thread. Even with large K-Horns, that have better bass than any Altec ever made, he still employs a sub.

    The 414 12" woofers have nice midrange but not exceptionally strong deep bass like a 15" Altec bass driver in the 825 or 828 Altec bass enclosures that are used in the A7's.

    Yes, the super-tweeters do provide a more level HF response above 10-kHz. Mine start rolling in above 6k.

    I prefer not to place active crossovers in the audio line.

    Altec's crossovers are not one of their stronger points.
     
  21. Ezd

    Ezd Forum Resident

    It never ceases to amaze me how cheaply vintage Altec Lansing speakers can still be occasionally found (I find them very under-valued compared to the sound they produce)... I noticed a pair of 9846-8A for $400 yesterday on Portland Craigslist, I have no idea about the condition of the surrounds and the crossovers should be updated, but the possibility of outstanding sound for little money and some effort is certainly there.
    I have too many speakers and audio projects or I would be driving to Portland myself. Someone in the area may want to check these out.

    [​IMG]
     
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  22. BillWojo

    BillWojo Forum Resident

    Location:
    Burlington, NJ
    My buddy and I have been experimenting with a set of A-7's and I must say the sound can be amazing.
    We tried 511 and 811 horns but as soon as we tried the Altec bent 32 horns we knew we had a winner. 802 or 902 drivers both sound good with the 902 having an extended range up high.
    Stock crossover sucks, my Model 19 crossover builds worked very well and were only bested by a set of Mast Mutter with autoformers.
    Good crossovers are a must in a 2 way Altec system. The Model 19 crossovers help flatten out the upper midrange bump and have HF attenuation as well. I use them in my HeathKit AS101's, basically Altec Valencias in much nicer cabinets.
    The Altec Users Board is a wealth of good info and there is a Lansing subforum on AK as well.
    With a little work those A-7 speakers will amaze you. The major problem with any Altec based speaker is dealing with the size. They go from big to huge!

    BillWojo
     
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  23. BillWojo

    BillWojo Forum Resident

    Location:
    Burlington, NJ
    Ezd, the woofers on those PA cabinets are NOT Altec, just beware.

    BillWojo
     
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  24. SandAndGlass

    SandAndGlass Twilight Forum Resident

    I had the 808-8A drivers with the symbiotic diaphragm in my original A7's, back when I was in high school.

    While I have the 902 drivers in the custom walnut cabinet A7's and they do have a more extended range. They have an aluminum diaphragm and it sound like an aluminum diaphragm, where the symbiotic diaphragm in the 908 series drivers that I have in my main pair of A7's, does not.

    To me, the symbiotic diaphragm has a far more natural sound.

    I have had the model 19's, and their crossovers are of a newer and more improved design. Still the attenuation that Altec crossovers use, sucks the life out of the HF.

    ALK crossovers are far superior to Altec OEM crossovers in every respect. Trying to make Altec frequency dividing networks to sound good, is like kicking a dead horse, tray as you may, you will achieve nothing.
     
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  25. PNW_M19

    PNW_M19 Active Member

    Location:
    98026
    Hi newbie here.

    Interesting thread regarding Altec crossovers. FWIW my personal experiences on an ~1 year journey gradually improving the audio performance of my Model 19's;
    - Initially updated my stock cross-overs with better capacitors and coils, no design changes. -> opened up the sound, extended highs and reduced harshness.
    - Sometimes I like to play loud, the 811 horns tend to ring. Placed Dynamat on outer side of the horn, the section of the horn that is inside cabinet (used the same mod on my former Klipsch RF7s) -> does not really make a difference. Experimented with placing roping caulk on the lips of the horns....roping caulk is still there .. IMHO it makes a difference.
    - One detail that made a big difference in my case, at initial visual inspection I thought the bug screens in the 802 compression drivers looked pretty clean. What was I wrong! After carefully removing the gunk with a tooth pick the highs opened up considerably, in a second phase I removed the bug screens all together (your personal consideration) which made another although smaller improvement.

    What really brought by M19's to an completely different level was the following; I purchased a MiniDSP SHD, this device has following 3 functions important to me:
    1) DLNA renderer, I exclusively listen to lossless audio files, stored on my media server
    2) State of the art room correction software - Dirac Live
    3) 2-way electronic cross-over with pretty advanced DSP processing capabilities, married with pretty decent DAC's, allowing me to make my system active.

    Going active is not just like disabling the passive crossover and set the Xo and filter type electronically and call it done. For myself it was a major time commitment by measuring and listening a lot (hobby -> no pain ;-). The MiniDSP comes with a calibration mic and you can download the REW software free of charge. The REW software enabled me to level the horns with the 416-8B drivers (yes big difference), but more importantly time align the speakers properly as well apply some PEQ per speaker to flatten & smoothen the frequency response. There are some good articles on the web how to use the REW software for this purpose and the MiniDSP SHD is very functional yet very user friendly in this regard. Once satisfied with a particular configuration, you run the DIRAC Live software, a simple process which can make a substantial difference in detail, imaging, etc. especially if speakers can't be optimally placed in the room.

    I'm done with optimizing and tinkering, just enjoy the music. Where I found my M19's to be pretty open but sometimes a bit edgy, now they completely disappear, are more dynamic and smooth. No way back for me to passive crossovers, well worth the investment in $$'s and time (please note I purchased all my equipment, no sponsoring).
     
    Ezd likes this.
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