[fxspec06]

I have a pair of technics a51 floorstanding speakers.

They are three way, 12" 3" 1".

I believe they are an old japanese model or something.

I have no idea where to begin to upgrade them.

But I know the box for each speaker is huge and I would love to have 12" subs on my fronts to compliment my SVS 10".

I have a polk audio cs10 for my center and psb alpha-1 for my surrounds.

Running on a Onkyo 506 reciever.



Please, if you are reading this and know anything about DYI and have the time and patience to deal with basically a n00b about speakers, help me out!



edit: If anyone was confused by that, I'm sorry. Basically what I want to do is rebuild my speakers ... drivers, crossovers, whatever else is necessary, but I want to keep the cabinet. I love the way they look.

 

[ph0rk]

polks tsi or monitor towers will match your center - the monitor 70's are on sale from newegg for $179 each (heavily discounted because they're being replaced with the tsi's).

use code EMCLSNN38 to get the $179 price. The monitors are hard to beat for $360 shipped.

 

[fxspec06]

Quote:

Originally Posted by ph0rk /img/forum/go_quote.gif polks tsi or monitor towers will match your center - the monitor 70's are on sale from newegg for $179 each (heavily discounted because they're being replaced with the tsi's). use code EMCLSNN38 to get the $179 price. The monitors are hard to beat for $360 shipped.

I'd rather try to rebuild the current speakers I have.

If that means stripping down the whole thing and doing it myself then so be it.

I'm basically new to DIY but I'm pretty smart at figuring things out. If I were to spend... say $150 per speaker, couldn't I make a better sounding pair than buying the monitor towers for $360?

 

[NightOwl]

You might end up with a better sounding pair of speakers for stereo music. There's an even greater chance that you won't. The drivers in the Technics weren't that great. So you could replace them. You would have to match the drivers and then match them to the type of box and volume of the enclosure. You would then have to design a 3-way crossover that matches your drivers and your enclosure. You're basically designing a new speaker for your existing enclosure. It ain't that easy.
If you want to build your own speakers, it's better to work from an existing design, buy the components and build them to spec (including the enclosures). Your cost would probably exceed $360.

The easiest possible improvement would be to upgrade the crossovers with better components of exactly the same values, but this also may not sound much better than the originals.

More importantly, for a surround system you have to match the timbre of your center channel with your front speakers or it will sound terrible. This usually means matching speakers from the same manufacturer. I guarantee you that the Technics will not match your center.
Bottom line, phOrk is right. Get the Polks and forget about the Technics unless you want to set up another system just for stereo.

 

[T.IIZUKA]

Hi,
Technics is an audio brand of Panasonic.
It is a model not sold in Japan.
(It is too large for the house in Japan. )

It might be reusable by the exchange of the edges of the unit.
Isn't there trader who is selling the trader or the edge to do the pasting substitution of the edge?

Specifications:
3 way, 3 speakers.
12" Woofer, 3" Midrange and 2" Tweeter.
8ohm impedance
200w input
92db/W sound pressure
30Hz-22kHz frequency range
38lbs a piece

 

[JadeEast]

I agree that trying to match the other speakers not be possible. If you want to do some modifications to your speakers there are a few things you can do that are cheap and can change the sound some what.

*I do not know these speakers at all so I'm speaking in general here about low/mid fi speakers.

Cheaper speakers are usually mechanically compromised, rap you knuckles on the top of the speakers and it'll probably sound very light. There are probably three things you want to do. Seal up the edge joints, add dampening and add bracing.

Pull the drivers out of them remove any stuffing that's in there and lay some nice beads of carpenters glue or silicone around the inside edges of the cabinet. Find something like a wooden dowel or piece of wood and create a couple of braces one that brace the cab internally from front to back. I don't know the speaker but if it's a three way above the woofer and under the mid would probably be good. To dampen the cab go to the dollar store or someplace cheap and find 3 to 6 big packs of kids plasticine and add it to the interior of the cabinets.

You can add dampening to the metal baskets of the woofers as well. These are mechanical changes where you're trying to make the cabinet stiffer and dampen it as well. Electrically I would probably just try to replace the caps in the crossover and maybe add a better tweeter. But best not to throw good money after bad so keep it within reason.

 

[Uncle Erik]

If you're dead set on keeping the cabinets, you should probably calculate their volume and contact Madisound to find appropriate drivers and to develop a crossover for you. You can pay them to do that for you. If you want to take a swing at it yourself, pick up the Loudspeaker Design Cookbook and work through it.

Also, keep in mind that you'll probably need to rework the cabinet, too. You'll have to get inside, replace the stuffing, line it with sound-deadening material and probably upgrade the binding posts, etc.

All in all, you can easily spend upwards of $500 to rework the cabinets into something better, buy new drivers and build new crossovers. Even then, they might not stack up all that well against better speakers that cost less. Especially used ones.

It's like spending $30k to tweak the hell out of an economy car when you could have picked up a pretty decent used Corvette for $10k that performs even better. On the same lines, keep in mind that you'll never get your money out of modded Technics speakers. No one else will ever buy them. But if you dropped that money on a pair of used, recognizable, speakers, you'll probably break even when you sell.

 

[islewind]

Quote:

Originally Posted by T.IIZUKA /img/forum/go_quote.gif Isn't there trader who is selling the trader or the edge to do the pasting substitution of the edge?

Amen to that!

 

[Lazarus Short]

My experience:

I have built a few pairs of speakers from scratch, cabinets + drivers. The results were OK.

My best friend had a pair of Fisher floorstanders like yours, three-ways with 12 inch woofers. We put in new mids and tweeters, and I hogged out the midrange holes. He was thrilled. In time he upgraded the woofers and crossovers, and later gave them to me. I was thrilled.

I have yet to justify buying new speakers to myself, though I did buy a Jamo sub/sat set at a garage sale for $20. They do not quite measure up.

So it can be done, just don't forget the speaker fill. Also, consider applying some damping sheets to the insides of the cabinets. Also, consider keeping the crossover outboard.

Laz

 

[Logistics]

In my experience, one of the easiest upgrades you can do is change the internal wiring. I've had so many people tell me that this should not make a noticable difference, and yet for me it does. Originally, I tried this on a pair of multi-media speakers which were internally wired with a very small, around the likes of 22ga or smaller, non-copper wire. I upgraded all of their internal wiring to 16ga (which is overkill, but heh) copper and there was more bass and cleaner highs.

I just ran into a pair of Onkyo S-31's and their wiring is also very tiny, probably 20-22ga so I'm going to be upgrading these for sure. Thankfully, the crossovers are attached to the jack-cup and not stapled to the inside somewhere so I'll upgrade it with whatever I can, even if the only reasonable choice is to go from electrolytics to bipolar electrolytics... haven't looked at them yet as I'm enjoying listening to them. Heh! Will add films where possible.

 

[Logistics]

I was just digging my Onkyo's out of the garage, and I got to thinking about the crossovers--I don't know how to design crossovers, but I could easily upgrade their components with better ones, including the inductors so long as I know their value.  However, this particular crossover is more mystifying to me as I don't know what the role of these large 8-Ohm inductors is, unless they are simply to regulate the load to approximately 8-Ohms.  Like I said, I don't know crossover design.
 
Could anyone tell by looking at these pictures, how I might redesign this crossover?  Do I need to have those inductors?  Could I do away with them?  Capacitors are easy to deal with, but if I don't need these 8-Ohm inductors, I'd like to delete them, and if I need them, I'd like to upgrade them to something better.
 
Matthew