I forget a question :
Is recommeded install the sub in a carpet room or it should be installed over hard floor.
Is recommeded install the sub in a carpet room or it should be installed over hard floor.
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Harman Kardon 245
hi, I just got a HK 245, with a bose acoustmass 10.
I setup very easy , and it is working well , but I have a couple of questions.
1. If the volumen is between -80 and -50 and I put my ear very close to the from speakers i could hear a hiss sound , does not matter wich input is used, tuner, dvd, sat, when the volumen is over -45 the hiss or hum noise disapear. I did a test with a little stereo with same volumen level , and i put my ear very close to the stereo speaker, and the his or hum level were higher than the Hk, so I gess the hiss noise is normal , the question is how much is normal o when is defect of the system?
2. I run the auto set for the system and it choose large speaker and crossover 40, but not choose any subass. Acording with bose instruction the crossover should be around 80, o lower but bose does no specify how much lower, so does a 40 cross over hurt the speaker? why the auto tuning doesnot detect the sub , I hear it when the hk did the test?
I setup very easy , and it is working well , but I have a couple of questions.
1. If the volumen is between -80 and -50 and I put my ear very close to the from speakers i could hear a hiss sound , does not matter wich input is used, tuner, dvd, sat, when the volumen is over -45 the hiss or hum noise disapear. I did a test with a little stereo with same volumen level , and i put my ear very close to the stereo speaker, and the his or hum level were higher than the Hk, so I gess the hiss noise is normal , the question is how much is normal o when is defect of the system?
2. I run the auto set for the system and it choose large speaker and crossover 40, but not choose any subass. Acording with bose instruction the crossover should be around 80, o lower but bose does no specify how much lower, so does a 40 cross over hurt the speaker? why the auto tuning doesnot detect the sub , I hear it when the hk did the test?
1 - 4 of 4 Posts
Although there are people on here that are far more knowledgeable than me, I'll take a crack at answering your questions.
1. As far as the hissing noice goes, the acoustmass 10's are really 4 ohm speakers that can, in theory, be run off a 8 ohm avr. In practice, the results are mixed. Because they have a lower impedence, the speakers require more power to generate the sound you are looking for. This "may" be the problem. Bose does not post efficiency ratings for their speakers (not sure why???), but I would imagine it's because these speakers are VERY inefficient (i am guessing below 80dB). This also explains how such tiny little speakers can handle up to 200 watts running through them. Don't be fooled into thinking more wattage capacity in a speaker is a great thing (it's only great when it's also efficient). In order to get these guys to work, you need to really pump up the volume.
Here's an experiment, put the avr in stereo mode (which bumps the wattage up). The hissing problem should resolve at a lower volume level than in surround mode. If you have your old speakers (probably 8 ohm, check the backs), try hooking two up to your fronts and run the avr in stereo. Is the hissing still there?? If so, the problem may rest with the avr. If not, it's your speakers and you should consider trying to return them (if you can). You could have a knock the house down speaker arrangement for the $1K you spent on the bose.
2. As far as crossover goes, the EZ setup feature is a great shortcut, but should not be viewed as a substitute for personal taste and judgment (it does save a lot of time though tinkering with a sound pressure guage and tape measure). I don't think a 40 crossover should be any problem at all for your sub and surrounds. The crossover is only shortening (or lenghtening) the frequency range that your sub kicks in. If you don't like the way your system sounds at 40, you can can experiment manually with a different crossover (80 is the standard a lot of manufacturers use (THX is set at 80). I personally enjoy hearing the richness and detail in the mid to highs, so i prefer a lower than default crossover frequency.
3. If you can return those Bose and you need a mini-satellite (which really never sounds as good as a "real" speaker), I would suggeest looking at some of the offerings by polk and infinity (which is a subdivision of harmon kardon). However, if size isn't an issue, with a 1000 bucks start a thread (what 5.1 speaker setup should I buy with a $1000 bucks) and you'll have a thread a million pages long from jealous audiophiles.
Just my 2 cents
Quote:
Originally Posted by heticor /forum/post/0
hi, I just got a HK 245, with a bose acoustmass 10.
I setup very easy , and it is working well , but I have a couple of questions.
1. If the volumen is between -80 and -50 and I put my ear very close to the from speakers i could hear a hiss sound , does not matter wich input is used, tuner, dvd, sat, when the volumen is over -45 the hiss or hum noise disapear. I did a test with a little stereo with same volumen level , and i put my ear very close to the stereo speaker, and the his or hum level were higher than the Hk, so I gess the hiss noise is normal , the question is how much is normal o when is defect of the system?
2. I run the auto set for the system and it choose large speaker and crossover 40, but not choose any subass. Acording with bose instruction the crossover should be around 80, o lower but bose does no specify how much lower, so does a 40 cross over hurt the speaker? why the auto tuning doesnot detect the sub , I hear it when the hk did the test?
Although there are people on here that are far more knowledgeable than me, I'll take a crack at answering your questions.
1. As far as the hissing noice goes, the acoustmass 10's are really 4 ohm speakers that can, in theory, be run off a 8 ohm avr. In practice, the results are mixed. Because they have a lower impedence, the speakers require more power to generate the sound you are looking for. This "may" be the problem. Bose does not post efficiency ratings for their speakers (not sure why???), but I would imagine it's because these speakers are VERY inefficient (i am guessing below 80dB). This also explains how such tiny little speakers can handle up to 200 watts running through them. Don't be fooled into thinking more wattage capacity in a speaker is a great thing (it's only great when it's also efficient). In order to get these guys to work, you need to really pump up the volume.
Here's an experiment, put the avr in stereo mode (which bumps the wattage up). The hissing problem should resolve at a lower volume level than in surround mode. If you have your old speakers (probably 8 ohm, check the backs), try hooking two up to your fronts and run the avr in stereo. Is the hissing still there?? If so, the problem may rest with the avr. If not, it's your speakers and you should consider trying to return them (if you can). You could have a knock the house down speaker arrangement for the $1K you spent on the bose.
2. As far as crossover goes, the EZ setup feature is a great shortcut, but should not be viewed as a substitute for personal taste and judgment (it does save a lot of time though tinkering with a sound pressure guage and tape measure). I don't think a 40 crossover should be any problem at all for your sub and surrounds. The crossover is only shortening (or lenghtening) the frequency range that your sub kicks in. If you don't like the way your system sounds at 40, you can can experiment manually with a different crossover (80 is the standard a lot of manufacturers use (THX is set at 80). I personally enjoy hearing the richness and detail in the mid to highs, so i prefer a lower than default crossover frequency.
3. If you can return those Bose and you need a mini-satellite (which really never sounds as good as a "real" speaker), I would suggeest looking at some of the offerings by polk and infinity (which is a subdivision of harmon kardon). However, if size isn't an issue, with a 1000 bucks start a thread (what 5.1 speaker setup should I buy with a $1000 bucks) and you'll have a thread a million pages long from jealous audiophiles.
Just my 2 cents
Your sub was probably not detected because it is not a real sub and probably has no output below 50 hz or so. Athena are not bad for a small system, defintely much better than Bose.
1 - 4 of 4 Posts
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