Modding the Primus series speakers

[jagxtype]

I have a pair of Primus 250's and remember someone knowing how to mod them to make them sound phenominal. I would appreciate it if either someone can guide me with a link to this thread or direct help on what would be required and what the results would likely to be compared with. I have used the search feature and read through LOTS of post til the end and saw nothing. Thanks in advance for the help.

 

[avaserfi]

This would be what you are looking for: http://forums.audioholics.com/forums/showpost.php?p=332680&postcount=14
http://forums.audioholics.com/forums/showthread.php?p=339520#post339520

The first is a link to suggested modification for the Primus 250s the second is another similar thread. If you have further questions feel free to ask.

 

[jagxtype]

Very good reads, but what can be expected of this. And could i improve my psw10 subwoofer as well using similar techniques? I have 2 Primus 250's, and 2 primus 150's. How hard is it to apply the dynamat to the inside of the bod through the small speaker openings? Is there any baffles in the 250 that i have to worry about? Is this mod worth the money and time required, or would i not notice a diffrence. Sorry for all the questions, but i have to thoroughly research everything before i act.

Also, using better quality speaker wire in the box; does it make a difference when compared to the original?

I have also heard that removing the grills would make a difference in sound, but i did it and i didnt notice it much if any at all. Any thoughts on this?

 

[avaserfi]

Very good reads, but what can be expected of this. And could i improve my psw10 subwoofer as well using similar techniques? I have 2 Primus 250's, and 2 primus 150's. How hard is it to apply the dynamat to the inside of the bod through the small speaker openings? Is there any baffles in the 250 that i have to worry about? Is this mod worth the money and time required, or would i not notice a diffrence. Sorry for all the questions, but i have to thoroughly research everything before i act.

Also, using better quality speaker wire in the box; does it make a difference when compared to the original?

I have also heard that removing the grills would make a difference in sound, but i did it and i didnt notice it much if any at all. Any thoughts on this?

The threads go over quality increases. Your actual response will become far more linear and less distortion will be introduced into the system from the cabinet.

As far as the modifications go it will require a bit of work, but if done properly the end result will be a far superior speaker.

Don't worry about changing speaker wire out thats what audiophools do. No audible differences will be detected.

A poorly designed grille can inhibit sound quality, but one properly done won't. That is a speaker specific problem.

These modifications likely won't help your subwoofer as most subs are braced sufficiently to stop resonant interference.

 

[jagxtype]

I just took one of the drivers out and it seems to have sufficient guage speaker wire anyhow. Speaker wire is speaker wire as long as it is the correct guage in my book. I will have to further think about modding. It will wait till spring at any rate. But if it will increase my indulgence of these already good sounding speakers, i may be willing to put forth the effort. And my shields are secure too, which is a relief. The only mods that i would be performing are the ones to improve the cobinet. Anyone ever had an idea of purchasing a subwoofer amp and subs and installing them into the enclosure. I am thinking this would be major modifications due to the solid baffle that would have to be installed limiting the woofers to a smaller area and the subwoofer would also most likely be deprived of needed volume. This might work to get stereo bass, but would likely muddy the sound of the speakers due to the box resonance. Any thoughts?

 

[mike c]

i don't think it would work well because the primus enclosure is ported. you would get lots of chuffing (aside from the volume requirements you mentioned)

 

[jagxtype]

i don't think it would work well because the primus enclosure is ported. you would get lots of chuffing

That is where the solid baffle would have to be installed to seal the bottom half and separate it into two different enclosures

 

[mike c]

i see. but I think even wmax would recommend a separate subwoofers.

it gives you flexibility in placement as well.

 

[jagxtype]

i agree, bu ti was just thinking about it for the "i wonder" factor. I agree that the two together often do not sound very well. its a wonder why the 250000-1,000,000 dollar speakers have separate towers...

The definitive tech speakers sound alright, but if the sub really startes to kick, it translates into muddy sound IMO. The infinity prelude (i think) are sub and driver combo. But if you note, they are completely isolated.

The PSW10 i have is a lightweight, but gets the job done. Throw a little newer age rap such as t-pain apple bottom jeans (let the flaming begin for listening to rap...) and that thing is going to get so overdriven its not even funny. I noticed today that it was just huffin so to speak when i got it loud. What do expect though, i paid $100 new for it and it has a 10" woofer on a 50 watt amp.

 

[avaserfi]

I would recommend removing the shielding on the drivers. I have 10+ Primus series drivers sitting in my bedroom and all have insufficiently attached shielding. This is a very simple process just use a rotary tool to cut it off.

As far as adding a subwoofer to the specific cabinet, why? The proper volume is not available for the application. Just use stereo subwoofers (a sub placed within 3 feet of each tower). All this information including how to integrate the subs is covered in the previously linked threads.

 

[Sheep]

I would recommend removing the shielding on the drivers. I have 10+ Primus series drivers sitting in my bedroom and all have insufficiently attached shielding. This is a very simple process just use a rotary tool to cut it off.

As far as adding a subwoofer to the specific cabinet, why? The proper volume is not available for the application. Just use stereo subwoofers (a sub placed within 3 feet of each tower). All this information including how to integrate the subs is covered in the previously linked threads.

Ladies and Gentlemen, I give you WmAx Jr.

SheepStar

 

[Joe Schmoe]

I don't get modding speakers. If you are going to go to that much effort and expense, why not build your own speakers? It seems like that would give better results.

 

[avaserfi]

I don't get modding speakers. If you are going to go to that much effort and expense, why not build your own speakers? It seems like that would give better results.

Modifying speakers versus building speakers are two completely different beasts. When modifying a speaker you can use an existing cabinet, crossover and driver design. Also, it can be far cheaper to purchase a speaker with quality drivers and modify the cabinet rather than build from scratch.

Building quality speakers from scratch requires an intimate understanding of perceptual research as well as a working knowledge of speaker design. This means one must be able to design a passive crossover or know how to implement an active one. Also, one must be able to choose appropriate, quality, drivers that will work well together. Lastly, one must be able to model these drivers and build an appropriate cabinet.

In the end, building speakers from start is far more involved, in every way, than modification of existing speakers.

 

[Joe Schmoe]

Most people don't know how to design speakers, which is why DIYers generally build kits. Living in an apartment, that is not an option for me, but I have read that the results are generally excellent.

 

[WmAx]

I don't get modding speakers. If you are going to go to that much effort and expense, why not build your own speakers? It seems like that would give better results.

In most cases, you are correct. However, some low cost pre-built speakers, though rare, have superb quality drivers and good crossovers, but are held back by very poor cabinetry systems. One such example is the Primus 360. It has a superb driver set and an excellent crossover. On and off axis response is superbly linear. Energy decay of the drivers is superb. The cabinet, however, is a pile of horse doodoo. Like most cabinets, the thing is resonant, and if that is not enough, it does not even use acosutic dampening material internally that is sufficient to absorb reflections/standing waves in the bandwidth of relevance. You could go so far as to put lesser quality drivers in a high quality cabinet, and end up with higher quality sound as compared to higher quality drivers in a low quality cabinet. The cabinet has that much influence. Ideally, the cabinet should have no influence(be neutral/inert) overall, but that is not the case with the vast majority of speaker systems, and that includes high cost 'audiophile' speakers.

-Chris

 

[Joe Schmoe]

Hmm...
What about making a cabinet with exactly the same internal dimensions and openings from a truly inert material (say 2" reinforced concrete, for example), and mounting the drivers in that?

 

[WmAx]

Hmm...
What about making a cabinet with exactly the same internal dimensions and openings from a truly inert material (say 2" reinforced concrete, for example), and mounting the drivers in that?

Concrete itself is not inert - but highly resonant. But it is stiff - reducing the amplitude of resonance appreciably. But you can use concrete with great success - just be sure to integrate a form of dampening in the construction to remove/reduce the resonant property. For example, you could shred up roofing tiles and mix them in the concrete(though this would probably weaken it substantially); or more feasibly, you could make one mold(internal with all internal chambers, etc.) then cover it in 1/2" of Peel N' seal or Dynamat. Glue a wire mesh to the outside of this materal to allow proper bindig of concrete to it. Then make a mold of concrete over this - ending up with a highly efficient constrained layer. In such a design, be sure to still use matrix bracing internally not more than 3" apart from any radius point if looking at any single wall. Of course, the problem is, moving the speaker after it's constructed. 2" walls of concrete, steel re-bar and internal bracing is not going to be lightweight.

-Chris

 

[Joe Schmoe]

Of course, the problem is, moving the speaker after it's constructed. 2" walls of concrete, steel re-bar and internal bracing is not going to be lightweight.

-Chris

Might be a good project for someone who owns a house and intends to stay put.

 

[Alex2507]

I don't get modding speakers. If you are going to go to that much effort and expense, why not build your own speakers? It seems like that would give better results.

This would be what you are looking for: http://forums.audioholics.com/forums/showpost.php?p=332680&postcount=14

Further along in that thread a suggestion is made for an active x-over, amp and subs all totaling in the $1000 range. A claim is made that the SQ would rival speakers in the $6000/pair range. That's all the reason I need to mod speakers.

 

[jagxtype]

I myself think that modding a speaker is a good idea compared to making it from scratch. Think of all the time, research, and measuring tools that they impliment into building any speaker of decent quality. Many people do not have these tools. If you start with something that already has a good base to build from, your just that much further ahead. Think of it as builing a house from scratch and remodeling a house. Each has its pros and cons. But a DIY person that does not specialize in the art of building a house is a lot better off handling a remodeling. The same principal to me, would also apply to a speaker.

On that thought...What about building a speaker from scratch with high quality wood and then using a sound dampening material to further better the structure built? Would this ideally be a better idea? I would have a general layout already being the original enclosure. I would have the drivers, crossovers, and whatnot from the speaker as well. Any thought on this? I am a newbie and like to toss ideas around...exercise my options fully.