Infinity Primus P162 mod possibilities?

[John Whiteker]

I am in the process of building my budget rig in order to rediscover the greatness of my vinyl collection. I grabbed these Infinity's today for $75 and they're like new. They're rated up to 150 watts and tonight, while pushing them through a Sony surround rig 100w x5 they seem to sound pretty good but my ears have become quite particular as to what I'm in search of. The tweeters here seem a little bright to me and I was just curious if anyone has tried adding some resistance to the tweeter circuit or changing the crossover. I really don't want to try and swap out the tweeter as it seems there's no direct drop-in replacement for them. Anyway, this receiver will be upgraded, along with adding a nice midrange phono preamp which may change things for the better, but I just think I'm still going to want to modify these a bit. Just curious if anyone out there has done any work to these units?

 

[WaynePflughaupt]

Your receiver has no treble control?

Regards,
Wayne A. Pflughaupt

 

[John Whiteker]

Well it does Wayne but me ears are quite used to the flat frequency response from the receiver so to me, with everything zeroed on the receiver it gives me a true representation of the speakers out of the box crossover settings. Not saying I couldn't adjust it. Just curious is all.

 

[Dennis Murphy]

Well it does Wayne but me ears are quite used to the flat frequency response from the receiver so to me, with everything zeroed on the receiver it gives me a true representation of the speakers out of the box crossover settings. Not saying I couldn't adjust it. Just curious is all.

From the looks of the measurements by Audioholics, I think you could improve things by adding a 1 or even 2 ohm resistor in line with the positive terminal of the tweeter. This doesn't appear to be a crossover issue--it's just a matter of the tweeter level voicing high up. Dayton non-inductive resistors are dirt cheap from Parts Express. Just unscrew the tweeter, cut the wire going to the positive terminal a couple of inches from the terminal, strip both ends of the cut wire, twist the bare wires around the resistor at each end so it's part of the signal path, and tape. You don't really need to solder. Given that shipping will probably be more than the cost of the resistors, you should probably order 2 one ohm and 2 two ohm, and probably start with the one ohm.

 

[slipperybidness]

From the looks of the measurements by Audioholics, I think you could improve things by adding a 1 or even 2 ohm resistor in line with the positive terminal of the tweeter. This doesn't appear to be a crossover issue--it's just a matter of the tweeter level voicing high up. Dayton non-inductive resistors are dirt cheap from Parts Express. Just unscrew the tweeter, cut the wire going to the positive terminal a couple of inches from the terminal, strip both ends of the cut wire, twist the bare wires around the resistor at each end so it's part of the signal path, and tape. You don't really need to solder. Given that shipping will probably be more than the cost of the resistors, you should probably order 2 one ohm and 2 two ohm, and probably start with the one ohm.

I assume the same mod would hold for the P363 Towers?

 

[Dennis Murphy]

I assume the same mod would hold for the P363 Towers?

I haven't seen a frequency response curve for those, so I don't know whether it would be justified. But it would bring down the highs by 1-2 dB

 

[jvm]

I have these speakers and love them! Carefully cut away the plastic ribs protecting the tweeter. Try a strip of felt between the tweeter and woofer, nearer the tweeter, tames the tweeter just enough. I also found some felt to the outside of the tweeter an inch or two, experiment a little, will stop some nasty reflections. Good luck!

 

[Dennis Murphy]

I have these speakers and love them! Carefully cut away the plastic ribs protecting the tweeter. Try a strip of felt between the tweeter and woofer, nearer the tweeter, tames the tweeter just enough. I also found some felt to the outside of the tweeter an inch or two, experiment a little, will stop some nasty reflections. Good luck!

You have to be careful about felt. If you apply it so that there's a raised edge near the dome, the sharp edge will cause more diffraction problems that it will cure. Madisound sells a felt disc with a hole in it the standard size of a 1" tweeter. I tried it and was amazed at how badly it messed up the frequency response

 

[j_garcia]

I have these speakers and love them! Carefully cut away the plastic ribs protecting the tweeter. Try a strip of felt between the tweeter and woofer, nearer the tweeter, tames the tweeter just enough. I also found some felt to the outside of the tweeter an inch or two, experiment a little, will stop some nasty reflections. Good luck!

When I love a speaker, it doesn't need any mods. I owned the P163s and did not love them.

 

[jvm]

This is what I've done, diffraction or no, with mods, I now love this speaker in my room to my ears. $3.00 for felt weather stripping, a buck for blue tack at dollar store. No harm in trying!

 

[PhillipLammers]

I have the harsh treble at loud volume issue but I'm looking for more bass. Does anyone have any ideas?

 

[PhillipLammers]

I am in the process of building my budget rig in order to rediscover the greatness of my vinyl collection. I grabbed these Infinity's today for $75 and they're like new. They're rated up to 150 watts and tonight, while pushing them through a Sony surround rig 100w x5 they seem to sound pretty good but my ears have become quite particular as to what I'm in search of. The tweeters here seem a little bright to me and I was just curious if anyone has tried adding some resistance to the tweeter circuit or changing the crossover. I really don't want to try and swap out the tweeter as it seems there's no direct drop-in replacement for them. Anyway, this receiver will be upgraded, along with adding a nice midrange phono preamp which may change things for the better, but I just think I'm still going to want to modify these a bit. Just curious if anyone out there has done any work to these units?

I understand there's a treble issue but I'm trying to get some bass out of mine. Any ideas?

 

[slipperybidness]

I have the harsh treble at loud volume issue but I'm looking for more bass. Does anyone have any ideas?

You should be getting plenty of bass out of these.

 

[PhillipLammers]

You should be getting plenty of bass out of these.

I added some damping material yesterday and improved the bass but it still doesn't impress me. My b&w dm303s have deeper bass and better treble response. Is it possible that they didn't install all the damping material that they should have?

 

[slipperybidness]

I added some damping material yesterday and improved the bass but it still doesn't impress me. My b&w dm303s have deeper bass and better treble response. Is it possible that they didn't install all the damping material that they should have?

The meager amount of damping material that they install in the Primus line doesn't really do much, it is pretty well known that you are better off removing it and installing DynaMat or Peal and Seal.

But, that should be helping to deal with cabinet resonances, not really getting you deeper bass.

 

[PhillipLammers]

The bass is better now but still not that good and I tried making the port longer before the damping material things and the longer port didn't help. I'm not concerned about cabinet resonance. The great cabinet is my favorite part of the speakers. But still the bass could be better and the tweeters only scream when I crank it loud. I'd appreciate any idea about the bass. Thanks

 

[slipperybidness]

The bass is better now but still not that good and I tried making the port longer before the damping material things and the longer port didn't help. I'm not concerned about cabinet resonance. The great cabinet is my favorite part of the speakers. But still the bass could be better and the tweeters only scream when I crank it loud. I'd appreciate any idea about the bass. Thanks

Have you played with positioning and toe-in?

A couple items of note:
https://www.stereophile.com/content/infinity-primus-p162-loudspeaker-measurements

The broad peak in the upper bass will be mainly due to the nearfield measurement technique, but the woofer tuning does look a little underdamped, which correlates with Bob Reina's finding the P162's low-frequency balance to be a little generous, despite its lack of true bass extension.

If all else fails, add a subwoofer (or 2)!

 

[PhillipLammers]

Have you played with positioning and toe-in?

A couple items of note:
https://www.stereophile.com/content/infinity-primus-p162-loudspeaker-measurements

The broad peak in the upper bass will be mainly due to the nearfield measurement technique, but the woofer tuning does look a little underdamped, which correlates with Bob Reina's finding the P162's low-frequency balance to be a little generous, despite its lack of true bass extension.

If all else fails, add a subwoofer (or 2)!

I've read that review countless times. These speakers never had the bass that stereophile claimed. I've tried them in many position with different amps. I want bass from these speakers. I've used them with subs. I will think of something

 

[lsiberian]

The bass is better now but still not that good and I tried making the port longer before the damping material things and the longer port didn't help. I'm not concerned about cabinet resonance. The great cabinet is my favorite part of the speakers. But still the bass could be better and the tweeters only scream when I crank it loud. I'd appreciate any idea about the bass. Thanks

Are you in a large room? My 5.25 inch 10 dollar drivers get plenty of bass in my small theater, but they'd struggle in a large room. Have you tried raising the crossover point between subwoofers and speakers to 120hz?

 

[PhillipLammers]

Are you in a large room? My 5.25 inch 10 dollar drivers get plenty of bass in my small theater, but they'd struggle in a large room. Have you tried raising the crossover point between subwoofers and speakers to 120hz?

I don't want to depend on a sub I think these speakers should be capable of solid bass down to at least 60 hz. I've used them with subs and they sound great but I don't like using the subs for music. I've used them in small room and large rooms. I've had them several years and tried all the placement method and I've got other small speakers that have much better bass. There must be a way to improve the bass. I might even change the drivers.