Cheap Speaker Upgrade/Mods: Yamaha NS-A836
- Thread starter ic-racer
- Start date
It seemed to compress a bit once it got it in there, but I can always take some out.
Although it looks like that is a 100% fill there was still a gap of exposed wood around the perimeter that I treated with some 3" x 1" strip. This was held in place with hot glue. Again, I'm just shooting from the hip here but my impression is that the original cabinet size was chosen for maximum "showroom floor presence" rather than for acoustic finesse. It is quite a big box for a 12" 3 way system.
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When you get them all assembled, check around the woofer & mid with a candle flame or a lighter to test the seal of that gasket material. Those grooves in it may keep you from getting an air tight seal.
Here is the Mid ready to go back in. Ignore the "+" and "-"...even though I double checked everything I still got it wrong. Note to anyone starting out in speaker building or modification. Purposely put your drivers out of phase and listed to it so you know what it sounds like. You may be surprised that if you have your head in the right position it does not sound bad and you can be fooled unless you check it both ways. Oh yea, these terminals were too far apart for my 9v battery and I was too lazy to make a jumper, so the lazy man takes the longest route.
Woofer in place. That rubber actually seals very well. Some of the other stuff McMaster carr has is more porous. This stuff is very dense and maintains its 'spring' very well under compression. Bottom line is that this particular material only comes with the textured surface and in this width, so not much option. I put those two pieces of rubber on the woofer frame but they seemed to make no difference to pinging the frame with my finger.
First listening impression compared to the other speaker.
The tweeter and mid are louder.
The peak mid driver frequency is lower. This makes the original speaker sound more like an alarm clock radio speaker by comparison.
The bass in the modified speaker makes the un-modified speaker sound muddy.
There is less high frequency program material produced by the woofer. By comparison the original speakers woofer's mid and high frequency response compete with and almost drowned out the other two drivers.
The tweeter and mid are louder.
The peak mid driver frequency is lower. This makes the original speaker sound more like an alarm clock radio speaker by comparison.
The bass in the modified speaker makes the un-modified speaker sound muddy.
There is less high frequency program material produced by the woofer. By comparison the original speakers woofer's mid and high frequency response compete with and almost drowned out the other two drivers.
bigaltx24
Super Member
I modded a pair of NS A-636s just to see how they would respond. Here's what i did.
Recapped crossovers with Dayton film caps.
Added bracing inside cabinet.
Damped woofer and mid baskets with putty tape.
They did wind up sounding better than stock, but like they say, all the lipstick in the world won't make a pig a beauty queen. All the mods in the world can't make up for bad design.
Recapped crossovers with Dayton film caps.
Added bracing inside cabinet.
Damped woofer and mid baskets with putty tape.
They did wind up sounding better than stock, but like they say, all the lipstick in the world won't make a pig a beauty queen. All the mods in the world can't make up for bad design.
mhardy6647
Lunatic Member
Just a thought... adding L-pads to the MR and HF channels of the XO (unless they're already too low in output) might not be a bad idea to 'tune' the output.
Yes. I was just looking through the Parts Express catalog and I see the L pads with faceplates. I could mount it on the back easily. I hope it uses a hole-saw size I already have. For simplicity sake I might just a single L pad on the mid.
UPDATE: I finished the second speaker. Now, listening to both speakers in the room I'm happy with the way they are.
On to the next project, which is to complete the restoration of my two JBL 4311B.
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Lessismore
New Member
Ok Im new here so and I reading up on some info on the NS-A635A with I just picked up for 15 bucks. Not the best spks I have herd BUT they are not bad? Iv herd worse thats for sure !!! First let me say Im running them on a flea watt chip! Well kinda , its like 30 watts or so? I do have a pair of Fostex H-1 bookshelf speaker, Kinda rare from what I gather?
The woofer and AMT tweeter is all fostex with very simple Xover ! I really dont think Xovers with make that great improvement you are looking for?
When a speaker is designed in a the way it is I would keep it that way!! With that said some of your best sounding spkshave very minimal or no Xover at all!!
With my SN-A635A I added foam to the cabinet it help allot! Mine have plenty of bottom end kinda tight? Better then my Fostex H-1s with better mids! But the treble does not come close!! Next I will replace the caps in the NS-A.. with higher quality ones and brace the cabs! Maybe look for a better tweeter that will fit?? On my little chip they sound very full but kinda boxy at times ? The bass is great!! faster and deeper then the H-1s ! Small chip amp with Mac, and the NS-A635A is sounding pretty darn good and plenty loud!!
I have had some very costly gear in the past and wasted lots and lots money down the old hifi road and now small chip amp with high SPL spks or DIY so much for and such great sound and fraction of the cost!!!
The woofer and AMT tweeter is all fostex with very simple Xover ! I really dont think Xovers with make that great improvement you are looking for?
When a speaker is designed in a the way it is I would keep it that way!! With that said some of your best sounding spkshave very minimal or no Xover at all!!
With my SN-A635A I added foam to the cabinet it help allot! Mine have plenty of bottom end kinda tight? Better then my Fostex H-1s with better mids! But the treble does not come close!! Next I will replace the caps in the NS-A.. with higher quality ones and brace the cabs! Maybe look for a better tweeter that will fit?? On my little chip they sound very full but kinda boxy at times ? The bass is great!! faster and deeper then the H-1s ! Small chip amp with Mac, and the NS-A635A is sounding pretty darn good and plenty loud!!
I have had some very costly gear in the past and wasted lots and lots money down the old hifi road and now small chip amp with high SPL spks or DIY so much for and such great sound and fraction of the cost!!!
Lessismore
New Member
Ok! Well back again some listening has been done on the NS-A.. ! I then hooked up my fostex H-1 bookshelfs and they are so,so easy two listen to!! Mids are are wormer/darker the treble does not in any way make your ears bleed!!! They just play music!! The AMT is very smooth on the fostex and the bass is there but a kinda subtle but nice? I blocked the ports with egg crate and they seem to be bit more articulate? Really the H-1s are hands down the better between the two! I listen to blues, jazz, classical, and they sound great!!
As for as the yamaha spks go maybe give them away to the rt person??
As for as the yamaha spks go maybe give them away to the rt person??
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lovefortubes
New Member
Pretty late , but i just picked up a pair and I dont think they sound that bad? No they are not high end spks but 12 bucks for pair is sweet!
Im running them on a EL34 tube and have compared with my kG2s and they have better mids but the highs just suck!
Im running them on a EL34 tube and have compared with my kG2s and they have better mids but the highs just suck!
NLT
New Member
I know I am 7 years late to the party but I have been upgrading Yamaha NS-A speakers into new cabinets and with upgraded crossovers, some generic, and have had fantastic success with making this line of speakers sing. People will tell you all kinds of crap about things 'not working' and those people are neither engineers nor willing to do development. I was pleasantly surprised to read what you had posted here, even 7 years later.
These speakers are currently in my workshop and get daily use. I have rotated many amplifiers through there. Currently they are driven by a newly restored Pioneer SA-800 and they are sounding great.
One day I may take them down from the top of the shelves they are on and sit them next to my JBLs and do a side-by-side comparison. I think they will fare very well. The Yamahas have a very tight bass response.
One day I may take them down from the top of the shelves they are on and sit them next to my JBLs and do a side-by-side comparison. I think they will fare very well. The Yamahas have a very tight bass response.