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Altec A7 What to do

Hello all, a Friend of mine has had Altec Lansing A7's sitting in his basement for several years, just couldn't put them in his current room setting. Many may know that I've been building for about 35 years. I built him a set of MTM's and delivered them for Christmas. He was thrilled. Well, today, he dropped off a pair of A7's and said they're yours. I sat them up and listened, thoroughly looked them over, looked up crossover design (500hz model) and now need to decide what to do with them. I have a decent size living room, but these are still huge. They do a lot of things right, but just aren't as refined as my current speakers. So, I've decided to sell them. I'm in no hurry to do so, but I know that I won't keep these forever. So, are these more desirable to sell as is... stock, upgrade parts in the crossover and sell them, redesign and trick out the crossover, cleanup, sand, minor fill and painting cabinets or some combination of the above. I have no doubt that a complete crossover redo, a bit of cabinet bracing and a good refinish and these babies would be incredible. The problem is... will people that don't know me accept or trust just how good they are? That being the case I'm looking for some advice. Please tell me how you would handle it in my shoes. Tim
timlub
kipduff
3 posts
 
timlub:

I have similar components: 416A (16 Ohm), 802D (16 Ohm), 511B, and N-500-E.  I have just aquired a pair of A7/828 empty cabinets.  My XOs are dead and I'm considering rebuilding/upgrading them.  If you are able, I could use some more detail.
* how did you get rid of the tar?
* brand/model/source of caps
* brand/model/source of resistors

I hink I have found an accurate diagram for N-500-E by "Peerless, Division of Altec Lansing".  C1: 4 mFd, C2 18.9 mFd, L1: 5.4 mH, L2: 5.4 mH.  Resistors: 2.5, 1.5, 1.5, 9, 6, and 10 Ohm.   

I'm pretty good at soldering and fabricating, but do not have understanding of how to select these capacitors and inductors and other details.  Thanks, Kip....
kipduff
3 posts
 
Well the tar came off easy.  I reken the most important part is the caps.
timlub OP
1,649 posts
 
@kipduff
Hi Kip,
If you are going to do a simple parts upgrade, measure the inductors, If they measure fine, just use them. If you are going to replace a diaphragm, if you can afford it, I’d replace them both. They could sound different from the originals and keeping them matched is important. Over time, I’ve played with alot of caps, for this project, I would replace C1 & C2 both with Jantzen Superior Z. Replace the resistors with Mills 12 watt non inductive. Overall these changes will be a true transformation to these speakers.
kipduff
3 posts
 
Thanks!
One value needed is 18.9uF- hook different caps in parrallel to add up to 18.9? 
timlub OP
1,649 posts
 
Hi Kip,
    Not sure of your budget....If no budget,  yes, get the Jantzen  superior z in a 12mfd and a 6.8mfd.....
If budget is an issue,  take a look at Solen PPE caps... the other Solens are ok too, but I clearly Prefer the PPE,  then get a Russian K71 polystyrene from Ebay.... this combination is very satisfying after a good break in...I have used the Solen, the K71 and Jantzen's all 3 paralleled together with very good results.... 
The K71 is very limited in its size availability.... they come in 1.0mfd.... 1.5mfd..... 5mfd and 10mfd.  You could use 10mfd of the styrenes and 12mics of another cap with very good results... I don't care for ANY of the other Russian caps on speakers. 
There are certainly other good caps,  but these are all very high bang for the buck,   Tim

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