Blows Subs?

[merovius]

Maybe about 5 years ago I bought the Cambridge Soundworks Newton Series T500 home theater surround system; would have hyperlinked but "no go" says Mr Admin.

Anyway, about a year after owning them and blasting the stereo at one of my former residences the subs blew... i think. I remember a very loud buzzing sound from the left one while it was plugged in, then it just completely died. Then the right one went. I never got around to replacing them due to financial constraints.

Im not exactly sure what happened, if the fuse blew or what. And while Ive replaced fuses on car audio amps before this looks a bit more difficult. The mids and tweets are fine so Im keeping them for the time being, but I dont have any bass. Im just guessing, but I think it could cost me upwards of around $500 to get them fixed.

I dont have the time or means (tools) to mess around with them myself (pulling apart the cabinetry etc) so if you were me would you get a new sub or pay to get 5+ year old speakers fixed? Seems like itd be an obvious answer.

Ive been looking at some new subs. Budget is <$1000, room is 27x24x8. Use is primarily TV, Movies, Video Games not so much music and parties anymore; getting old blows.

Im looking for tight, clean, punchy bass. 8" 10" or 12" powered sub, crossover, dont know much about radiator design (active vs passive) and what would be optimal for my usage.

What do you guys think about these subs?
JL f110 (overbudget but JLs sound sick)
Boston rps1000
Polk microPro 1000
Paradigm (havent researched)
Klipsch (havent researched)
HSU (just heard accolades from this forum)

I know thats a lot of info so thanks for your time and any advice is appreciated.

Cheers

 

[TLS Guy]

Maybe about 5 years ago I bought the Cambridge Soundworks Newton Series T500 home theater surround system; would have hyperlinked but "no go" says Mr Admin.

Anyway, about a year after owning them and blasting the stereo at one of my former residences the subs blew... i think. I remember a very loud buzzing sound from the left one while it was plugged in, then it just completely died. Then the right one went. I never got around to replacing them due to financial constraints.

Im not exactly sure what happened, if the fuse blew or what. And while Ive replaced fuses on car audio amps before this looks a bit more difficult. The mids and tweets are fine so Im keeping them for the time being, but I dont have any bass. Im just guessing, but I think it could cost me upwards of around $500 to get them fixed.

I dont have the time or means (tools) to mess around with them myself (pulling apart the cabinetry etc) so if you were me would you get a new sub or pay to get 5+ year old speakers fixed? Seems like itd be an obvious answer.

Ive been looking at some new subs. Budget is <$1000, room is 27x24x8. Use is primarily TV, Movies, Video Games not so much music and parties anymore; getting old blows.

Im looking for tight, clean, punchy bass. 8" 10" or 12" powered sub, crossover, dont know much about radiator design (active vs passive) and what would be optimal for my usage.

What do you guys think about these subs?
JL f110 (overbudget but JLs sound sick)
Boston rps1000
Polk microPro 1000
Paradigm (havent researched)
Klipsch (havent researched)
HSU (just heard accolades from this forum)

I know thats a lot of info so thanks for your time and any advice is appreciated.

Cheers

Those speakers are a nice design by the late Harry Kloss. It is an integrated design, not suitable for pairing with another sub.

I would have the speakers repaired if you can. Your other alternative is to ditch them and start again.

You will not get much of a speaker system for the cost of repairing those, certainly nothing of comparable quality.

 

[sholling]

That's about 4700cuft which is doable with a single sub. I'd forget the speaker companies and contact SVSound and Hsu Research and have them size you a sub.

 

[highfigh]

Those speakers are a nice design by the late Harry Kloss. It is an integrated design, not suitable for pairing with another sub.

I would have the speakers repaired if you can. Your other alternative is to ditch them and start again.

You will not get much of a speaker system for the cost of repairing those, certainly nothing of comparable quality.

Harry Kloss- is that Henry's brother?

 

[TLS Guy]

Harry Kloss- is that Henry's brother?

He was usually known as Harry.

 

[sholling]

Those speakers are a nice design by the late Harry Kloss. It is an integrated design, not suitable for pairing with another sub.

I would have the speakers repaired if you can. Your other alternative is to ditch them and start again.

You will not get much of a speaker system for the cost of repairing those, certainly nothing of comparable quality.

I'm surprised you can't pair them with a sub but I defer to your greater knowledge about these speakers. Hopefully there is someone that fixes these.

 

[TLS Guy]

I'm surprised you can't pair them with a sub but I defer to your greater knowledge about these speakers. Hopefully there is someone that fixes these.

It is a full integrated crossover to the 6.5" speaker. So the 10" driver in the side is not getting just the sub signal. It is a little like my set up where the bass line is doing more duty than the LFE channel. You could not replace my lower section with a standard sub either.

Cambridge Sound works are still a going concern, so he should start by contacting them for service.

 

[Seth=L]

It is a full integrated crossover to the 6.5" speaker. So the 10" driver in the side is not getting just the sub signal. It is a little like my set up where the bass line is doing more duty than the LFE channel. You could not replace my lower section with a standard sub either.

Cambridge Sound works are still a going concern, so he should start by contacting them for service.

Would not a pair of subwoofers integrate just fine with those speakers? Do we know the cross-over point between the 10" woofers and 6.5" mid-bass?

 

[merovius]

Thanks for the replies. Just realized I jacked up the thread title, posting late at night ftl.

Took your advice and looked into repairing. I just got off the phone with Cambridge and Ill be heading over to Radio Shack at some point to locate replacement fuses. 2.5 Amp 250 Volts 4A Fuse 5x20mm slow blow (timed released)

Apparently they made them really accessible and I hadnt realised it. Theres a little plastic flip door on the bottom that opens with a flathead. I really hope its just fuses.

Cambridge doesnt have any qualified vendors or certified repair specialists but repair is rather inexpensive. If its not the fuses theyll send me a pamphlet on removing the amp, then its $75 to repair each (includes shipping). 150 isnt bad.

 

[TLS Guy]

Would not a pair of subwoofers integrate just fine with those speakers? Do we know the cross-over point between the 10" woofers and 6.5" mid-bass?

I had a good look at this yesterday. Crossover points are not mentioned.

However the connections are to the left right speaker terminals and a sub out to sub in, with another RCA audio cable linking the subs.

Now the instruction manual says the left right mains setting of a receiver has to be set to large. In addition to a control for the sub level, there is a bass blend.

This tells me that the 10" driver is handling more than the sub LFE signal.

It would be logical that the 10" driver at least carries the step response correction for the forward facing speakers.

The reason is that the best way of off loading a bass mid driver and a receiver. And it gives you control of diffraction compensation on a room by room basis which is optimal.

Step response starts at 6 db per octave at 600 Hz for that speaker based on dimensions. So if you work that out, that is a lot of power the receiver has to provide and the 6.5" driver handle.

We hear a lot about subs off loading receivers and drivers. This really is not so to all intense and purposes.

What does save receiver amp power and stress to small bass mids, though is to let a larger speaker and amp handle the diffraction compensation. That is why I do that.

In a usual HT set up with a crossover at 80 Hz the tuning peaks of impedance of the mains kicks in at that point, so the receiver is relieved of very little power with the usual sub crossover points.

The instruction manual says the front facing speakers can be powered with as little as 10 watts per channel.

If you design an integrated system, it is a no brainer to engineer it this way, and I bet Harry Kloss would have seen it right away.

So more than likely operating it with two usual type subs would still leave it sounding thin.

 

[Seth=L]

I had a good look at this yesterday. Crossover points are not mentioned.

However the connections are to the left right speaker terminals and a sub out to sub in, with another RCA audio cable linking the subs.

Now the instruction manual says the left right mains setting of a receiver has to be set to large. In addition to a control for the sub level, there is a bass blend.

This tells me that the 10" driver is handling more than the sub LFE signal.

It would be logical that the 10" driver at least carries the step response correction for the forward facing speakers.

The reason is that the best way of off loading a bass mid driver and a receiver. And it gives you control of diffraction compensation on a room by room basis which is optimal.

Step response starts at 6 db per octave at 600 Hz for that speaker based on dimensions. So if you work that out, that is a lot of power the receiver has to provide and the 6.5" driver handle.

We hear a lot about subs off loading receivers and drivers. This really is not so to all intense and purposes.

What does save receiver amp power and stress to small bass mids, though is to let a larger speaker and amp handle the diffraction compensation. That is why I do that.

In a usual HT set up with a crossover at 80 Hz the tuning peaks of impedance of the mains kicks in at that point, so the receiver is relieved of very little power with the usual sub crossover points.

The instruction manual says the front facing speakers can be powered with as little as 10 watts per channel.

If you design an integrated system, it is a no brainer to engineer it this way, and I bet Harry Kloss would have seen it right away.

So more than likely operating it with two usual type subs would still leave it sounding thin.

I power my speakers with 25 watts per channel and don't have problems with output, so to say a speaker can be driven with as little as 10 watts means next to nothing. In fact many speakers have suitable amplifier ranges that start at 10 watts.

The T500 user manual states the speakers can be safely used with a receiver or amplifier that has an output of at least 30 watts. I'm not sure where you read 10 watts (a review perhaps?).

I like how Cambridge has an overal lack of specifications available for these speakers; however the manual seems to indicate the that 100hz is where the subwoofer should be crossed over.

 

[yepimonfire]

it would be simple to find out the x-over, just start playing sinewaves at various frequencies starting at 70hz, if you cant hear 70, go up 10hz, if you can hear 70, go down 10 hz until you cant hear it, then narrow it down by 1hz at a time, OP if you want i can prepare sine waves for you and send them to you via mp3, you could burn the to a cd or better yet run it through an ipod or similar device.

an even better idea would be to externally power the subs once you know the x-over, you could use external amps and your receivers subout, but of course that would take some work, and money.

 

[yepimonfire]

may be going a bit off track but....

I power my speakers with 25 watts per channel and don't have problems with output, so to say a speaker can be driven with as little as 10 watts means next to nothing. In fact many speakers have suitable amplifier ranges that start at 10 watts.

this has alot to do with you speakers sensitivity an the amount of volume and space your hoping to gain/fill. you also need headroom like if you NEED 25w of power you should use a 50wpc amp so that your not clipping on bass peaks and musical peaks. whats more important then the power handling and power output is your speakers sensitivity rating, this is the key to determining how much power your gonna need to fill a space with clean sound. for instance, most bookshelfs average on 87db 1w/1m this means that in order to have enjoyable volume from music and movies, your going to need a minimum of 25 watts because that gives you an increase of 14db (101db) at 1m, but most people are not sitting 1m from their sound system, to fill a living worth of space you would need 50 wats giving you a volume of 104db at 1m, but since your sitting approx 2-3m away, the perceived volume will be 1/3 at 2m and 1/9 at 3m so i would say that for moderate volume levels your going to need 50w clean, meaning best stick with a 70w amp for headroom in peaks. but in a small apartment or small room 25wpc will give decent listening levels because you will not be able to practically sit that far from your speakers nor will you have very much air volume to displace. in the case of high sensitivity speakers (ones with 92db 1w1m or above) a 25wpc amp could cause hearing damage. so its not really about how much power can i drive through them, its about how efficiently they are going to use that power. ive seen 1000w capable PA speakers that can be blown out of the room by 150w ones somply because of a difference in sensitivity.

 

[lsiberian]

may be going a bit off track but....




this has alot to do with you speakers sensitivity an the amount of volume and space your hoping to gain/fill. you also need headroom like if you NEED 25w of power you should use a 50wpc amp so that your not clipping on bass peaks and musical peaks. whats more important then the power handling and power output is your speakers sensitivity rating, this is the key to determining how much power your gonna need to fill a space with clean sound. for instance, most bookshelfs average on 87db 1w/1m this means that in order to have enjoyable volume from music and movies, your going to need a minimum of 25 watts because that gives you an increase of 14db (101db) at 1m, but most people are not sitting 1m from their sound system, to fill a living worth of space you would need 50 wats giving you a volume of 104db at 1m, but since your sitting approx 2-3m away, the perceived volume will be 1/3 at 2m and 1/9 at 3m so i would say that for moderate volume levels your going to need 50w clean, meaning best stick with a 70w amp for headroom in peaks. but in a small apartment or small room 25wpc will give decent listening levels because you will not be able to practically sit that far from your speakers nor will you have very much air volume to displace. in the case of high sensitivity speakers (ones with 92db 1w1m or above) a 25wpc amp could cause hearing damage. so its not really about how much power can i drive through them, its about how efficiently they are going to use that power. ive seen 1000w capable PA speakers that can be blown out of the room by 150w ones somply because of a difference in sensitivity.

Sensitivity tells you more about the crossover than the drivers many times. A 93 db/1m rating usually indicates a lack of Baffle Step compensation. Meaning the bass is weaker.

Speaker design is full of trade offs. This is one of many.

 

[Seth=L]

Sensitivity tells you more about the crossover than the drivers many times. A 93 db/1m rating usually indicates a lack of Baffle Step compensation. Meaning the bass is weaker.

Speaker design is full of trade offs. This is one of many.

Everything is about trade-offs. Smaller speaker with lower frequency output characteristically will have lower impedance, reduced sensitivity, and increased cost. Cerwin Vega speakers are the exact opposite, large, loud, very sensitive, cheap, and sound like grumpy in a garbage can with a horn tweeter on top.