Need help. Polk Lsi15 uneven sound
The left speaker sound is louder than the right one. I suspect the cap in the right speaker crossover is defected. Is it right? or because of other issues? Pls advice.
Answers
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You either cooked a resistor (a common issue with those speakers) and/or cooked the tweeter.
Remove the crossover and look for a burnt/cracked resistor. If you don't see a problem then swap the tweeters. If the problem follows the tweeter then it is dead, which isn't good as Polk doesn't have any.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
I'm with F1Nut on checking the tweeter or resistor, though is it possible you have a woofer connection come loose? I bumped my CS400i a while back and a woofer cable got knocked off and it sounded quieter, I just plugged it back in and was off to the races.
Best thing is pull the crossover as F1 said and inspect the resistors, simple fix with a 12W Mills if they've been cooked. Put an empty toilet paper tube around the tweeter and hold your ear to it, does the tweeter work? Finally, check the wiring to the drivers inside. -
Have you swapped the cables to verify it is the speaker.
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I did swap the cables. Swapped with another speakers pairs and the sound was just normal. I'll check the crossover and report back what I found. Thks for quick reply.
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Did you swap cables left - right and did the right one still play quieter? If so then it is the speaker. If the left then played quieter than it is something with your source / amp / cables.Stan
Main 2ch:
Polk LSi15 (DB840 upgrade), Parasound: P/LD-1100, HCA-1000A; Denon: DVD-2910, DRM-800A; Benchmark DAC1, Monster HTS3600-MKII, Grado SR-225i; Technics SL-J2, Parasound PPH-100.
HT:
Marantz SR7010, Polk: RTA11TL (RDO198-1, XO and Damping Upgrades), S4, CS250, PSW110 , Marantz UD5005, Pioneer PL-530, Panasonic TC-P42S60
Other stuff:
Denon: DRA-835R, AVR-888, DCD-660, DRM-700A, DRR-780; Polk: S8, Monitor 5A, 5B, TSi100, RM7, PSW10 (DXi104 upgrade); Pioneer: CT-6R; Onkyo CP-1046F; Ortofon OM5E, Marantz: PM5004, CD5004, CDR-615; Parasound C/PT-600, HCA-800ii, Sony CDP-650ESD, Technics SA 5070, B&W DM601 -
I could not find any resistors on the crossover.
pic1 is the bottom of the crossover, there are 2 inductors and 2 capacitors.
pic2 is the top of the crossover, there are 4 black capacitors, 4 white inductors, and 1 round inductor. Where is the resistor location?
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Because it is at the L2 silkscreen so at first I thought the 4 white rectangular items on the top of crossover are inductors. Actually they are resistors. 5W2R0J is the 5watts 2 Ohms resistor, isn't it?
There are no burnt marks on the resistors so the tweeter is defected. -
Because it is at the L2 silkscreen so at first I thought the 4 white rectangular items on the top of crossover are inductors. Actually they are resistors. 5W2R0J is the 5watts 2 Ohms resistor, isn't it?
You're right on the money.
The resistors to me look completely fine. I'd recommend replacing then anyways with 12W Mills as I recall the LSi series has some issue with the wattage on the resistors being too low or something, which can damage the tweeter or crossover board. I don't recall the specifics.
Are the metal jumpers between the binding posts there? If you don't know what I'm referring to, just send a photo of the plugs for the speaker wire. -
Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
Before shopping for a new tweeter, I'll use the LRC meter for checking all caps.
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Waste of time.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
I'm not gonna go buy some LSi speakers and fry the resistors just so I have 'experience' with it. It doesn't take a genius to know 5W is too low. -
Why is 5 watt too low? -
Generally a tweeter uses 10-20 percent of the power a speaker is drawing. The LSi is an 88dB sensitive speaker and all it takes is one social gathering. If you got your friends together and had the speakers in the living room and you were out in the kitchen, you'd probably be playing them at 85dB or so and that's like 10 meters or so away at minimum. To drive the speakers like that, the tweeters will already be pulling 5W or so at the high end, which is literally the highest limit of that resistor.
You shouldn't drive speakers that loud anyways if you want to keep your hearing, but you know, some people do, and the drivers can handle it but the resistors will burn up because they're being driven to their limit or PAST their limit.
Also consider the fact that there are peaks in volume in songs and power spikes as well, makes for a great way to burn up a resistor. They're also glued to the board so they don't dissipate heat as well. -
Could it be that most folks do not feed them good clean power and run a receiver into clipping ?
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Could it be that most folks do not feed them good clean power and run a receiver into clipping ?
This would do it too, but it would damage the drivers before the resistor. I'm going to eventually go through all of my RT series speakers and replace the resistors with Mills MRA-12 just to prevent them from burning up if I ever crank the volume (not that the tri-lams could handle it) just incase, but it wouldn't do me good if my Onkyo started clipping.
On a side note it turns out my Onkyo wasn't clipping, the voice coil on my left RT3000p SL6502 was deformed and crackling... so that's fixed now and it turns out my Onkyo can push 85dB (my personal limit) no problem so long as the bass frequencies are left to my subs!
I'm pretty sure the LSi series did specifically have an issue with the 5W resistors, I went through some of forum pages and confirmed this, so I'd recommend installing an MRA-12 anyways, but a tweeter dying... clipping is probably the culprit. Consumer gear sucks.
Can't wait to nab some Emotiva amps. -
WRONGThis would do it too, but it would damage the drivers before the resistor.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
WRONGThis would do it too, but it would damage the drivers before the resistor.
Really? Hm, I'll look into it more. I researched it before and I came to that conclusion but the internet is a bag of mixed info. -
Because it is at the L2 silkscreen so at first I thought the 4 white rectangular items on the top of crossover are inductors. Actually they are resistors. 5W2R0J is the 5watts 2 Ohms resistor, isn't it?
You're right on the money.
The resistors to me look completely fine. I'd recommend replacing then anyways with 12W Mills as I recall the LSi series has some issue with the wattage on the resistors being too low or something, which can damage the tweeter or crossover board. I don't recall the specifics.
Are the metal jumpers between the binding posts there? If you don't know what I'm referring to, just send a photo of the plugs for the speaker wire.
Yes, they are. I'll replace all resistors as you suggested. -
I found a post about alternative Lsi15 tweeter
https://forum.polkaudio.com/discussion/175474/lsi15-tweeter-replacement.
Is Tymphany driver XT25TG30-04 1" the best replacement for the tweeter RD0517-2 (used in LSi15) after outer flange removal?
quote from K_M: "It is the exact same one, except for the Face Plate. It was verified by the Polk Marketing Guy (Paul DiComo) on another audio forum."
I don't have a RD0517-2 spec so can't compare it to XT25TG30-04 spec
https://www.parts-express.com/pedocs/specs/264-1016--tymphany-xt25tg30-04-spec-sheet.pdf
However XT25TG30-04 spec looks good at on axis response, starts roll off at about 9KHz on 30 deg, and gets worst at about 7KHz on 60 deg. Should I buy XT25TG30-04? they are available at Digi Key and Part Express for $29 each. -
Well I do remember the posted thread. If Paul DiComo (R.I.P.) said it was off the shelf with the exception of minor faceplate differences, you can bet he was correct. That being said, you really have none or very few options at this point for replacement. Buy two, three or four depending on how many spares you want on hand for the future.
Maybe I over looked, what you are running them with ? Receiver or amp? -
I found a post about alternative Lsi15 tweeter
https://forum.polkaudio.com/discussion/175474/lsi15-tweeter-replacement.
Is Tymphany driver XT25TG30-04 1" the best replacement for the tweeter RD0517-2 (used in LSi15) after outer flange removal?
quote from K_M: "It is the exact same one, except for the Face Plate. It was verified by the Polk Marketing Guy (Paul DiComo) on another audio forum."
I don't have a RD0517-2 spec so can't compare it to XT25TG30-04 spec
https://www.parts-express.com/pedocs/specs/264-1016--tymphany-xt25tg30-04-spec-sheet.pdf
However XT25TG30-04 spec looks good at on axis response, starts roll off at about 9KHz on 30 deg, and gets worst at about 7KHz on 60 deg. Should I buy XT25TG30-04? they are available at Digi Key and Part Express for $29 each.
Get the Peerless (Tymphany) XT25TG30-04 and swap the faceplate. I recall reading in a thread where someone did this exact tweeter swap and a member of the forum said LSi models after 2005/2006 have glued faceplates. Make sure you can remove your faceplate by simply unscrewing it before ordering those, otherwise decide if you want to source an original or hack up the new faceplate. -
Well I do remember the posted thread. If Paul DiComo (R.I.P.) said it was off the shelf with the exception of minor faceplate differences, you can bet he was correct. That being said, you really have none or very few options at this point for replacement. Buy two, three or four depending on how many spares you want on hand for the future.
Maybe I over looked, what you are running them with ? Receiver or amp?
Parasound A21+ -
looking at 12W Mills resistors at soniccraft.com, there are no equivalent 2 and 3.5 Ohms value.
10W Mills resistors doesn't have them either.
Only 5W Mills resistors has 2 and 3.5 Ohms value. Should I buy 2 each and put them in parallel to get 10W? -
looking at 12W Mills resistors at soniccraft.com, there are no equivalent 2 and 3.5 Ohms value.
10W Mills resistors doesn't have them either.
Only 5W Mills resistors has 2 and 3.5 Ohms value. Should I buy 2 each and put them in parallel to get 10W?
Parts Express, Parts Conexxion, and soniccraft does have them:https://www.soniccraft.com/product_info.php/35-ohm-vishay-mills-mra-12-p-5222 -
Is there any different btw Vishay Mills and Mills brand? It looks like they have them same built spec.
quote from soniccraft.com for Vishay Mills brand: " Sonic Craft has found the current Vishay/Mills resistor to be an acceptable replacement for the original Mills resistor. It is non-magnetic, non-inductive, and wire-wound. The all weld construction uses an Alumina ceramic core with a Copper-Nickel or Nickel Chrome element (depending on value), Copper alloy end-caps, and tinned Copper leads. Aryton-Perry winding greatly reduces inductive reactance and signal loss. All Vishay/Mills are gloss Brown, and marked made in Mexico.
All of our Vishay/Mills resistor values are 1% tolerance. The MRA-12 (12 watt power rating) will handle overloads 10X its power rating (120 watts) for 5 seconds with operating voltages up to 1000V."
quote from soniccraft.com for Mills brand: " The Mills resistor is a non-magnetic, non-inductive, and wire-wound that was specifically designed for high-end electronics, loudspeakers, and audiophile upgrades. The all weld axial construction boasts an Alumina ceramic core with a Cuprum or Ni-Chrome element, Silver plated Copper alloy end-caps, and tinned Copper leads. Aryton-Perry winding greatly reduces inductive reactance, signal loss, and allows a Cuprum element to be used up to four times the value of most.
The Mills MRA resistors exceed MIL-R-26E specs, and satisfy MIL-STD-202, method 106, 208, and 218. All resistor values are 1% tolerance. The MRA-12 (12 watt power rating) will handle overloads 10X its power rating (120 watts) for 5 seconds with operating voltages up to 1000V. " -
Is there any different btw Vishay Mills and Mills brand? It looks like they have them same built spec.
quote from soniccraft.com for Vishay Mills brand: " Sonic Craft has found the current Vishay/Mills resistor to be an acceptable replacement for the original Mills resistor. It is non-magnetic, non-inductive, and wire-wound. The all weld construction uses an Alumina ceramic core with a Copper-Nickel or Nickel Chrome element (depending on value), Copper alloy end-caps, and tinned Copper leads. Aryton-Perry winding greatly reduces inductive reactance and signal loss. All Vishay/Mills are gloss Brown, and marked made in Mexico.
All of our Vishay/Mills resistor values are 1% tolerance. The MRA-12 (12 watt power rating) will handle overloads 10X its power rating (120 watts) for 5 seconds with operating voltages up to 1000V."
quote from soniccraft.com for Mills brand: " The Mills resistor is a non-magnetic, non-inductive, and wire-wound that was specifically designed for high-end electronics, loudspeakers, and audiophile upgrades. The all weld axial construction boasts an Alumina ceramic core with a Cuprum or Ni-Chrome element, Silver plated Copper alloy end-caps, and tinned Copper leads. Aryton-Perry winding greatly reduces inductive reactance, signal loss, and allows a Cuprum element to be used up to four times the value of most.
The Mills MRA resistors exceed MIL-R-26E specs, and satisfy MIL-STD-202, method 106, 208, and 218. All resistor values are 1% tolerance. The MRA-12 (12 watt power rating) will handle overloads 10X its power rating (120 watts) for 5 seconds with operating voltages up to 1000V. "
I'm pretty sure that Vishay makes Mills resistors now. For my M5JR+ refresh, I personally bought the Vishay Mills MRA-12 1 ohm. -
Toasty!
I did not do this. It was other kids.Stan
Main 2ch:
Polk LSi15 (DB840 upgrade), Parasound: P/LD-1100, HCA-1000A; Denon: DVD-2910, DRM-800A; Benchmark DAC1, Monster HTS3600-MKII, Grado SR-225i; Technics SL-J2, Parasound PPH-100.
HT:
Marantz SR7010, Polk: RTA11TL (RDO198-1, XO and Damping Upgrades), S4, CS250, PSW110 , Marantz UD5005, Pioneer PL-530, Panasonic TC-P42S60
Other stuff:
Denon: DRA-835R, AVR-888, DCD-660, DRM-700A, DRR-780; Polk: S8, Monitor 5A, 5B, TSi100, RM7, PSW10 (DXi104 upgrade); Pioneer: CT-6R; Onkyo CP-1046F; Ortofon OM5E, Marantz: PM5004, CD5004, CDR-615; Parasound C/PT-600, HCA-800ii, Sony CDP-650ESD, Technics SA 5070, B&W DM601 -
https://www.soniccraft.com/product_info.php/35-ohm-vishay-mills-mra-12-p-5222?osCsid=0qq425sgd26kk3cirooivckg44
https://www.soniccraft.com/product_info.php/ohm-vishay-mills-mra-12-p-5330?osCsid=0qq425sgd26kk3cirooivckg44
Yes Vishay bought Mills years ago. Jeff still has the original Mills and as you see only a limited stock of values. -
I managed to disassemble the Lsi15 tweeter and removed the damaged voice coil diaphragm. Should I rebuild it with the third party voice coil on Ebay ( about $18 ) in order to keep the original tweeter magnet or buy the Peerless (Tymphany) XT25TG30-04 tweeter? ( about $28 ). Are the magnet on these 2 the same type? Also does it helps the sound if I add ferrofluid?
