Guys - Please help me decide my 5.1 speaker system

[AcuDefTechGuy]

I think as long as you are not trying to play > 90dB reference volume, you will be just fine.

Onkyo amps are usually serious amps. Even if they don't say "4 ohms", I think they will be able to handle 4 ohms just fine as long as you don't go crazy on the volume.

If you are in the "better safe than sorry" camp, then minimum impedance is more important.

That may be one reason most of us have separate amps - better safe than sorry.

Well, actually the reason most of us have separate amps is because we are audioholics.

 

[Sylar]

Measurements seem to suggest that above 500Hz things are not an issue. the impedance starts to dip at lower than 500Hz frequencies. From around 80Hz to 300Hz impedance is hovering around 4 ohm mark. This suggests that this requires more power in this bass region.
Similarly the 30hz - 60hz region. Of course, specs state this speaker as 60hz to 20kHz (45hz is the -3dB cutoff). So this shouldn't be much of a concern and I think one shd strive to set a higher crossover here.

Audioholics here could give a better picture if the 608 can drive this. I think not.
But oof course, am still a rookie with this stuff...so still learning

 

[jostenmeat]

Look, it might be fine for your needs, and it may not be fine. Things like the volumes you crank it to, the source material, the distance you sit from the speakers, it all plays a role.

Therefore, all I can basically say is that if it sounds bad at all, turn it down. This should help you ensure that you avoid blowing either an amp or driver. Do that, and you will very likely be just fine.

If you want to worry less about it, you'd have to throw more money at it perhaps, but since that is not an option play: if it sounds bad, immediately turn it down.

 

[Sylar]

I think as long as you are not trying to play > 90dB reference volume, you will be just fine.

Onkyo amps are usually serious amps. Even if they don't say "4 ohms", I think they will be able to handle 4 ohms just fine as long as you don't go crazy on the volume.

If you are in the "better safe than sorry" camp, then minimum impedance is more important.

That may be one reason most of us have separate amps - better safe than sorry.

Well, actually the reason most of us have separate amps is because we are audioholics.

Damn he beat me to it. It took me a while to read the specs and chart to try analyze.

I am kinda wondering how did you get the 90dB number. Here is my analogy, do correct me if I am wrong here.

1. Presuming the calibrated amp plays at 105 dB ref level at max volume, 15 dB down is like pushing around 1 - 10 watts to speakers, right? Hence enough power/headroom reaming to safely drive the speakers without loosing composure or being driven into clipping. But, with every 3 dB rise, changes things quickly from this point.

2. When calibrated, they are calibrated at 105 dB. All calibrated amps play max at reference of 105 dB. Other than for getting the extra capability for the amp to play 4 ohm loads at reference levels with loosing composure or been driven into clipping (obtained with a better PSU). What is the need of more expensive and capable amps for HT use? I was recommended recently 4310 for T6 which has this extra head room, with which I wouldnt have to worry about the volume knob (but just my ears ). Is it that there are some other speakers which have more ugly impedance charts, & hence the need lot more headroom than what the 4310 would provide?

Even if they don't say "4 ohms", I think they will be able to handle 4 ohms just fine as long as you don't go crazy on the volume.

Is there a way to limit this on an amp other than the need to forcefully be aware of this? What is the risk he faces if he pushes to the limit? Other than loosing composure, playing with more harmonic distortion & clipping. Is the amp or tweeter at risk here? I think the tweeter could be, but amp? Wouldnt the tweeter blow before amp is damaged?

Can he not 'fool the calibration process' by bringing the mike closer to source and hence setting the ref @ less that 105? Any disadvantages here? Not sure what else is done during the calibration process other than setting reference levels.

 

[Sylar]

4) or do I necessarily need a 4 ohms AVR ? ( it will be too costly option to sell Onkyo 608 and buy another AVR as i bought 608 from US and hence it cost me less and if i have to buy another one it will have to be from my country i.e India and AVRS here are atleast twice as expensive as in the US )

hmmmmmmm

I am kinda currently stuck with my AVR choice. I was going to do the same, until I was bought down to earth...thanks to audioholics

So Maybe it might be of interest to you too...but you have already made the jump.
http://forums.audioholics.com/forums/showthread.php?t=73893
http://forums.audioholics.com/forums/showthread.php?t=73886

Was just wondering....Would this this compound his problem further - using a stepdown on top oof lacking ability of driving an 4 ohm load with ease?

 

[naren2512]

Dear All,

Thank you very much for sharing your ideas and trying to guide n help me out. It kind of seems little scary to me now

Is it ok and safe to at least to try to use my Onkyo 608 AVR with PSB Image B6? and if i feel the sound quality is worsening at any volume level i will put either bring it down or shut my AVR for some time.

If i don't face any problem ( wishful thinking !!) i.e if i dont find the sound quality to be worsening at the volume level at which i might like watching movies then i can continue this way, else i will think of any other possible alternative at that point of time.

Do you guys think it will be worthwhile to try above?

Regards,
Naren

 

[naren2512]

Was just wondering....Would this this compound his problem further - using a stepdown on top oof lacking ability of driving an 4 ohm load with ease?

I would definitely need to use a step down as the AVR is from the US. so thanks for bringing this up.

I would appreciate comments / views on this as well

 

[jostenmeat]

I haven't been following the step down thread, but it appeared to me that it's definitely something to avoid if you can help it. Otherwise, I myself would be fine with driving the B6 with something like a 608 (if it's similar to Onkyo receivers of generations past, in terms of power), as long as I kept my expectations in check, and/or that I sat relatively close to the speakers.

Yes, I think you can have this all work out just fine. When I mean "sounding bad", I do mean any kind of unnatural distortion.

I don't think 4 ohms is much to worry about if the volumes are only moderate. Really, the volume desired at the seated position is the big deal, and the further away you sit, the much greater this need for power becomes.

For example, for the same SPL at 5ft away vs 20 ft away, you would need SIXTEEN times more power at 20ft away than at 5ft.

 

[zieglj01]

Is it ok and safe to at least to try to use my Onkyo 608 AVR with PSB Image B6? and if i feel the sound quality is worsening at any volume level i will put either bring it down or shut my AVR for some time.

Do you guys think it will be worthwhile to try above?

Regards,
Naren

It is a good starting point for now.

 

[k_lewis]

Hi Friends,

I need some serious advise and help here !!!

I have made my mind for PSB Image bookshelves and already own an ONKYO 608 AVR.

Now the problem is that the specs of the PSB Image speakers suggest this: Impedance - Nominal 6 Ohms, Minimum 4 Ohms

While the specs of my AVR ( Onkyo 608 ) suggest : Speaker Impedance - 6 ohms–16 ohms

My questions are :

1) Is it nominal impedence or the minimum impedence that is important to be considered for Speaker - AVR matching?

2) Can my AVR drive the Image book shelves properly ?

3) Is there a possibility that my AVR can damage ? and hence will I have to be careful about at what volume I play them at ?

4) or do I necessarily need a 4 ohms AVR ? ( it will be too costly option to sell Onkyo 608 and buy another AVR as i bought 608 from US and hence it cost me less and if i have to buy another one it will have to be from my country i.e India and AVRS here are atleast twice as expensive as in the US )

Thank you very much for your help in advance

Regards,
Naren

You'll be totally fine- Hook them up to the AVR and rock on! Onkyo makes very well built products. Make sure you use some decent gauge speaker wire if they will be long runs more than 10 feet. Finding a decent reliable step down that can handle some amperage pulled though it might not be cheap though.

 

[naren2512]

Hi Everyone,

Thanks for your help so far.

I read the Onkyo 608 user manual yesterday it says it has speakers impedance of 6-16, but it also says that Asian and European models can support 4 ohms speakers but the North American models cant ( and mine is a later)

In reality could it be that the AVR can actually support 4 ohms but since 4 ohms AVRs have to undergo more serious testings etc ( some ULC testing i read it some where ) hence onkyo AVR says no for 4 ohms for North American models?

Or could there really be difference in the amplifier of the same model AVR beign sold in two different regions / two different parts of the world ?

Regards,
Naren

 

[zieglj01]

If you do not feel comfortable - then do not do it. You will not enjoy
your speakers - if you are going to worry about it. The system is a
decent starting point for now, keep the volume at moderate levels.
I have never had a problem driving a PSB Image speaker, with an
average type receiver. I would think about saving up for a stronger
receiver, as time goes by.

 

[naren2512]

If you do not feel comfortable - then do not do it. You will not enjoy
your speakers - if you are going to worry about it. The system is a
decent starting point for now, keep the volume at moderate levels.
I have never had a problem driving a PSB Image speaker, with an
average type receiver. I would think about saving up for a stronger
receiver, as time goes by.

HiZieglj01,

Thanks for your response and I am definitely not giving up on pairing my Onkyo 608 with PSB Image B6!! Although I need to be careful about the volume levels but I am not worried too much any more about this pairing after the helpful response from you and other great audioholic members here

Btw - May I know which AVR and PSB Image combination have you been using and since when?

Now I am just trying to understand if the onkyo 608 is actually capable of supporting 4 ohms ( i.e if its a 4 ohms AVR) although the specs say its a 6ohms AVR and this question / doubt came to my mind becasue its user manual says speaker impedance is 6-16 ohms but it also says the European and Asian Modles support 4 ohms speaker but north american models do not - and mine is a norht american model )

There could be two possibilities I think :

1) The Amp inside the AVR is same for the European and North American models both and hence even North American models support 4 ohms speakers and the user manuals probably says the 4 ohms speakers are not supported becuase they want to avoid the serious testing that the 4 ohms AVRS have to undergo ( I read it somewhere about it and i think its called something like a ULS or ULC testing but not too sure about it may be you guys can guide me on this and i might be completely wrong so guys please feel free to correct me on this )

2) The Amp inside the European and North american models are differnt and that the North American models actually do not support 4 ohms !

What do you guys think of above? any ideas / comments will be highly appreciated !!

Regards,
Naren

 

[zieglj01]

HiZieglj01,

Btw - May I know which AVR and PSB Image combination have you been using and since when?

Now I am just trying to understand if the onkyo 608 is actually capable of supporting 4 ohms ( i.e if its a 4 ohms AVR) although the specs say its a 6ohms AVR and this question / doubt came to my mind becasue its user manual says speaker impedance is 6-16 ohms Regards,
Naren

I have used receivers like Sherwood and Pioneer in the past. The last
one was a Marantz receiver - I do not have a Image speaker anymore.
Onkyo is protecting themselves with the ohm ratings, and that makes
sense to me. The American model may be modified from the other ones.

The 608 is rated lower in 6 ohms, than 8 ohms - that is why they will
not guarantee a 4 ohm rating. Look at the 1000 khz ratings.

Power Output -
Front L/R 100 W + 100 W (8 ohms, 20 Hz-20 kHz,
0.08%, 2 channels driven, FTC)
100 W + 100 W (6 ohms, 1 kHz, 0.1%,
2 channels driven, FTC)
Center 100 W (8 ohms, 20 Hz–20 kHz, 0.08%,
2 channels driven, FTC)
100 W (6 ohms, 1 kHz, 0.1%, 2 channels
driven, FTC)
Surround L/R 100 W + 100 W (8 ohms, 20 Hz–20 kHz,
0.08%, 2 channels driven, FTC)
100 W + 100 W (6 ohms, 1 kHz, 0.1%,
2 channels driven, FTC)
Surround Back L/R 100 W + 100 W (8 ohms, 20 Hz–20 kHz,
0.08%, 2 channels driven, FTC)
100 W + 100 W (6 ohms, 1 kHz, 0.1%,
2 channels driven, FTC)
Dynamic Power 240 W (3 ohms, 1 ch)
210 W (4 ohms, 1 ch)
120 W (8 ohms, 1 ch)
THD (Total Harmonic Distortion) 0.08% (Rated power)

 

[Sylar]

If you are in the "better safe than sorry" camp, then minimum impedance is more important.

That may be one reason most of us have separate amps - better safe than sorry.

I guess this says it all.
Even if the amp is not rated at 4 by the manufacturer, it might work out for you. Then again this might not. This is the reason i decided to go the safe route of pairing it right, even though cost seemed to cause an issue (I didnt want to be forcefully aware of my volume knob or of distortion all the time). With more distortion, and less headroom left, more power is delivered into the hi frequency region. The tweeter being more vulnerable, would be at risk here. Would it or wont it be damaged, depends on too many factors. The tweeter itself might have a better thermal rating than what the manufacturer stated in the specs, and hence no need to worry...but again maybe not. I think the point here is you don't know unless you try it out for sure.

So I guess in your case, for the time being since you already have the amp, be a little careful of the volume knob and you dont have to always worry.

Also if you dont have regulated voltage, then with a voltage drop (which is kinda common in India), the amp could suck in more current to compensate for the drop. Not sure if this is relevant in this context or if it could cause any negative effects.

Is the manufacturer warranty valid here if the tweeter is damaged in this scenario??

 

[Sylar]

Damn he beat me to it. It took me a while to read the specs and chart to try analyze.

I am kinda wondering how did you get the 90dB number. Here is my analogy, do correct me if I am wrong here.

1. Presuming the calibrated amp plays at 105 dB ref level at max volume, 15 dB down is like pushing around 1 - 10 watts to speakers, right? Hence enough power/headroom reaming to safely drive the speakers without loosing composure or being driven into clipping. But, with every 3 dB rise, changes things quickly from this point.

2. When calibrated, they are calibrated at 105 dB. All calibrated amps play max at reference of 105 dB. Other than for getting the extra capability for the amp to play 4 ohm loads at reference levels with loosing composure or been driven into clipping (obtained with a better PSU). What is the need of more expensive and capable amps for HT use? I was recommended recently 4310 for T6 which has this extra head room, with which I wouldnt have to worry about the volume knob (but just my ears ). Is it that there are some other speakers which have more ugly impedance charts, & hence the need lot more headroom than what the 4310 would provide?


Is there a way to limit this on an amp other than the need to forcefully be aware of this? What is the risk he faces if he pushes to the limit? Other than loosing composure, playing with more harmonic distortion & clipping. Is the amp or tweeter at risk here? I think the tweeter could be, but amp? Wouldnt the tweeter blow before amp is damaged?

Can he not 'fool the calibration process' by bringing the mike closer to source and hence setting the ref @ less that 105? Any disadvantages here? Not sure what else is done during the calibration process other than setting reference levels.

No replies

I guess this says it all.
Even if the amp is not rated at 4 by the manufacturer, it might work out for you. Then again this might not. This is the reason i decided to go the safe route of pairing it right, even though cost seemed to cause an issue (I didnt want to be forcefully aware of my volume knob or of distortion all the time). With more distortion, and less headroom left, more power is delivered into the hi frequency region. The tweeter being more vulnerable, would be at risk here. Would it or wont it be damaged, depends on too many factors. The tweeter itself might have a better thermal rating than what the manufacturer stated in the specs, and hence no need to worry...but again maybe not. I think the point here is you don't know unless you try it out for sure.

So I guess in your case, for the time being since you already have the amp, be a little careful of the volume knob and you dont have to always worry.

Also if you dont have regulated voltage, then with a voltage drop (which is kinda common in India), the amp could suck in more current to compensate for the drop. Not sure if this is relevant in this context or if it could cause any negative effects.

Is the manufacturer warranty valid here if the tweeter is damaged in this scenario??

No replies here either. Does this mean my analogy was so bad that ignoring this was the best reply

 

[MATMAN1970]

Narin,

You seemed very concerned with your receiver's ability to drive these speakers. Over the course of the last year I put together a bang for your buck system for my Dad. His room dimensions are similar to yours and he sits a few feet closer. At 14 feet away, you will be putting a great strain on your speaker's (especially the tweeter) and receiver if you ever want to listen at anything close to reference level. I was very close to going with the same PSB set-up as you did, I auditioned them and the whole bit. I was worried about the juice of the receiver and was considering a separate amp(Emotiva XPA-3) which would cost more $$$. In the end I ended up going with a pro designed speaker that had high sensitivity and directionality. That solved my worrying about clean listening volume and power needs since I can drive them to reference levels using just a receiver (Denon 3310).

Just some food for thought since I was in the same boat as you with the same concerns.

Matt

 

[cpp]

a pro designed speaker that had high sensitivity and directionality

very well said.

 

[naren2512]

Narin,

You seemed very concerned with your receiver's ability to drive these speakers. Over the course of the last year I put together a bang for your buck system for my Dad. His room dimensions are similar to yours and he sits a few feet closer. At 14 feet away, you will be putting a great strain on your speaker's (especially the tweeter) and receiver if you ever want to listen at anything close to reference level. I was very close to going with the same PSB set-up as you did, I auditioned them and the whole bit. I was worried about the juice of the receiver and was considering a separate amp(Emotiva XPA-3) which would cost more $$$. In the end I ended up going with a pro designed speaker that had high sensitivity and directionality. That solved my worrying about clean listening volume and power needs since I can drive them to reference levels using just a receiver (Denon 3310).

Just some food for thought since I was in the same boat as you with the same concerns.

Matt

Thanks for sharing your experiance, but i think i liked PSB Image B6 after trying quite a few different speakers hence again trying to look for a different set of speakers will be difficult, so i am goona take a chance and run PSB Image B6 on Onkyo 608 AVR incase i dont like the pairing i will probably sell my AVR after a few months or may be a year and buy another one.

Regards,
Naren

 

[MATMAN1970]

@3db



4) PSB Image - Unfortunately the dealer dint have PSB Image B6 and i got to audition this combination (Image B5 *2 in fronts, B4*2 in rears with C5 center) the receiver used was Onkyo 608

The PSB was smooth and neutral sound and something that wont cause fatigue, however when I tried to play at higher volume i could not handle it i mean sound was not clear and it was putting strain on my ears. The salesperson at the store said PSBs are non fatiguing and that they were sounding not so good at high volume because these were completely new set of speakers which i was the first one to demo and they will get better after burn in period.

I hope B6 would be better than B5 and if they are then i will most likely buy them for my fronts.


Naren.

Thanks for sharing your experiance, but i think i liked PSB Image B6 after trying quite a few different speakers hence again trying to look for a different set of speakers will be difficult, so i am goona take a chance and run PSB Image B6 on Onkyo 608 AVR incase i dont like the pairing i will probably sell my AVR after a few months or may be a year and buy another one.

Regards,
Naren

No problem, like I said the B6, C5 etc..etc.. was what I almost went with. I still consider myself a PSB semi-fanboy. You quote above does worry me since the burn in period will not make the PSB sound better at higher volume no matter what the salesman says(and they say alot). You are probably hearing compression and distortion due to the speaker's design and rather low sensitivity. A new AVR will not solve that problem since I am assuming the sales guy was driving it with a decent unit. If you are going to do some low to moderate listening levels then you will be ok, but at 14 feet distance you will not be able to do much more then that. I am not saying this to be a stick in the mud, it is just that your situation was very close to mine.

Matt