Visaton FRS8 8ohm or 4ohm to choose?

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Hi, I'm using Cyburg's needles over a year, it sounds great, but it's not why I'm here.
I'm going to use the same FRS8 in car with midbass helix h206. The crossover frequency is going to be about 800-1000Hz. Typically 4ohm speakers are used in cars, thats what I was going to do, but does 4ohm FRS8 sounds the same as 8ohm FRS8? In other words, what do I miss if I choose 4ohm FRS8? Has anyone compared?
Any ideas are wellcome:)
 
richie00boy said:
I would always go for the higher impedance given a choice between 4 and 8 ohms, all other things being equal. Less current leading to less losses, and easier on the amp.

I agree - but then there's the case when you're using Tripath amps. There's a pretty low voltage maximum in those, but they're usually proportionally better at handling current. There's other things involved too; Most Tripath amps are specifically designed for 4 Ohm loads.

What amp will you be using?
 
I agree that when you have the voltage available to drive them higher impedance speakers are preferable, but in an automotive application the very reason that 4 ohm speakers are used is that these amplifiers often cannot develop the voltage necessary to properly drive an 8 ohm speaker. Even so, the penalty for using 8 ohm speakers will be loss of a few dB at most. Unless you are striving for an SPL record I would choose the 8 ohm speaker. As already mentioned, less loss in wiring, etc. plus the damping factor of the amp becomes twice as much.

I understand that you are asking about the difference in sound between the two drivers, and that certainly is the most important thing, but I can't comment on that having never heard either one. Maybe someone else has compared them.
 
If I have to choose what impedance speakers to use at home, I'd doubtlessly choose higher impedance.
The poblem I see is that I'm going to use two speakers on one amp chanel (Helix h206 and FRS8 with passive crossover at 800Hz). Helix has much higher sensivity, so I have lack of sensivity on FRS8. If I choose 8ohm FRS8, the amp would provide less power at 8 ohm, so I'd loose about 3dB more. Correct me if I'm wrong. I guess that the choice is between FRS8 4ohm ant FRS8 M 8Ohm (has much higher sensivity).
Of couse the most important thing is the sound. If there is no big difference in sound between FRS8, I'd go fo 4ohm one.
 
I realise that one can't make judgments about sound quality based on specifications but you can make some generalisations. Having studied the specifications of the three drivers, and assuming that they are correct, none of these three drivers should sound the same at all. The 8 ohm version, which you have been using, has a Qts of 1.04 whereas the 4 ohm version has a Qts of 0.69. Most of the other specs, except for voice coil inductance, are the same or nearly the same but that difference in the Q will probably be noticeable.

On the other hand, the 8-M is a whole different driver. It has a stonger magnet and lighter membrane, which lowers the Qts to 0.49 but improves efficiency from 82 dB-1M/1W to 88 dB-1M/1W. The inductance is also lower than either of the other two drivers which will alter the high frequency response.

It's hard to say whether you would like the sound of the 4 ohm unit or the 8M if you are trying obtain the sound of the FRS 8-8 that you are familiar with. In my experience, a speaker has to be heard to determine whether it meets with your expectations and it is very possible that you may have to purchase and listen to some, but then turn right around and put them on eBay and buy a different set to audition.

Hope this has helped a little.
 
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