B&w 801

[sonosphere]

@sonosphere
How would you describe "Taiwanese sound" of Usher X-718 /Be-718 type of bookshelves?

What I posted was more in the nature of light hearted banter.Not meant to be taken seriously....

Hi Ajay,
I am aware that many generalizations in audio (and elsewhere) are not supposed to be taken as rule. However I've read so much about British /American /Canadian sound that it appears that there is some truth to it.

I've found speakers like Wharfe, Quad, PSB, Polk, B&W, Paradigm (all bookshelves only) to be very much in line with the generalization reg country of origin. This must be having something the do with the sonic preferences of the local market these brands operate in. Considering Usher's sell a lot in south-east asia, I was wondering how their sonic signature would be described. (I read one remark on web saying Usher V-601 shares the same signature as "718 series"... considering this, I would call the signature slightly midrange-ish compared to earlier brands, yet real /neutral sounding)

BTW I recently compared a Marantz CDP and an Arcam CDP playing Neil Diamond's Forever in blue jeans. Marantz sounded neutral yet enjoyable, and Arcam sounded "magicaly" warm without missing out an ounce of detail. I emotionally connected more with Arcam than Marantz. Maybe you'll find difficult to let go your Arcam even though you find "better" CDP.

@ arj (well although usher is a Taiwanese Co..the designer is an American. so any philosophy needs to be american as well)

If Polk Audio RTI A1 bookshelf, is a sample of "American signature" (the way Wharfe/Quads represent British) then I would say Ushers are not American sounding. I found these Polks to be "harsh", i.e "away from refined sound" (Polk lovers, please don't flame me). The Usher V-601's are anything but "harsh"

Regds,
Sonosphere

 

[sonosphere]

Actually this is only Part fact. eg a harbeth with 86dB can easily run with a 25Watter, but a BW in the 88-90dB needs at least 100 W
the sensitivity can be a deceptive number unless seen with the impedence and phase curves across the frequency ranges

....

Hi arj,
I suppose the bolds above (mine) is very important fact for those who rely on sensitivity criteria to shortlist their speakers for audition. This fact shows that it can be a mis-leading criteria.

The fact above almost sounds contradictory (though I am not doubting your info) If you know, can you share why this happens?

Regds,
Sonosphere

 

[prem]

Hi Sonosphere

Its because of the impedance

 

[odyssey]

Hi Sonosphere
it works like this -

the ratings of 88db or 85 or 90 etc are all given assuming an 8 ohm impedance or rather thats the general trend. Realistically it is meant to say 1W of power is consumed when a voltage of 2.83V is applied with a resistance of 8 ohms and that gives so and so sound levels at 1m.

Power = (V^2/R). Now some manufacturers play games with this (IMO, much like the PMPO nonsense) and say 90dB, however the impedance can be 2 ohms - so what happens? it then means that 90dbm of sound pressure is produced at 1m, when 4W is applied -> (2.83^2)/2 = 4
so it takes 4W to get 90dB, in other words its the same as a speaker that does 84dB at 1W (every double of wattage gives a 3dB higher sound pressure).
Many people interchange the terms speaker efficiency and speaker sensitivity, they do not mean the same thing and this is where the confusion lies.

by the way, the above does not even take into other factors such as complex phase or lower impedance which makes it further hard to drive (from an amp output stage perspecive).

cheers

 

[arj]

Adding on to Odysseys post, the impedance is not the same across the frequency spectrum. it varies..some speakers like B&W 805 have it dropping to 3 ohms and below in the 30-50 Hz range. Now if your amp cannot instantaneously give the current, you will have the speakers not able generate the required SPL.

if this was simple, there is another aspect ie Phase which kind of denotes the amount of Capacitance/inductance. hence if the phase is off by 45 deg for 4ohms impedance, the power required could be much higher than for a speaker with an easy phase variation at 3 ohms.

to further complicate, till now we were talking about the speaker..the amp also has a similar curve ie different power output across the frequency range..and that should exceed the requirement by the speaker.

to make it even worse..all this generates a specific sound output in a room (let not even get into room acoustics )..now our own ears have a specific reception curve (ie higher sensitivity to different frequencies)

so overall thats why each setup/ear can soud so different

 

[sonosphere]

Wow! I've just experienced a moment of "mini-enlightenment"!

I had some idea of the concepts spoken above, though as scattered bits of info. With arj, prem and odyssey's explanations the concepts have suddenly become part of single picture.

Thanks a lot!

regds,
Sonosphere

 

[prem]

Hi Sonosphere, it is because of the impedance dip that it becomes very difficult to drive certain speakers like the Martin Logans. Very few amps drive them well.

 

[sidvee]

Adding on to Odysseys post, the impedance is not the same across the frequency spectrum. it varies..some speakers like B&W 805 have it dropping to 3 ohms and below in the 30-50 Hz range.

Arj - You may be referring to the 805s or the diamond 805, because the lowest impedence of the N805 is 4.8 ohms at 200hz and consequently relatively easy to drive. I have been using my 60 watt tube amps. to drive them very well indeed.
B&W Nautilus 805 loudspeaker Measurements | Stereophile.com
Cheers
Sid

 

[arj]

you are right Sidvee.. i do remember another speaker which had the problem.
But the 805 has impedence exceeding 20 Ohms..that would make it easy to drive. but the amp needs to be a high current source..something which Tube amps are usually very good at.

 

[arj]

@ arj (well although usher is a Taiwanese Co..the designer is an American. so any philosophy needs to be american as well)

If Polk Audio RTI A1 bookshelf, is a sample of "American signature" (the way Wharfe/Quads represent British) then I would say Ushers are not American sounding. I found these Polks to be "harsh", i.e "away from refined sound" (Polk lovers, please don't flame me). The Usher V-601's are anything but "harsh"

Regds,
Sonosphere

just saw this... if you ignore the entry level, Polk , as in many american speakers has a very strong presence. Strong treble. hard hitting bass and a tight midband. ( heard some of their older Floorstanders many years ago) they are now not the same company they once were...mathew polk was one of the leading lights in audio

 

[shershah]

But the 805 has impedence exceeding 20 Ohms..that would make it easy to drive. but the amp needs to be a high current source..something which Tube amps are usually very good at.

Valves are high voltage and low current devices in contrast to transistors, which typically operate at lower voltages and higher currents for the same power level

 

[arj]

you are right, that is the statement wikipedia will give you for tube amps but i believe once you transformer couple them..they do it a lot better

 

[shershah]

that is the statement wikipedia will give you for tube amps

 

[arj]

Arj - You may be referring to the 805s or the diamond 805, because the lowest impedence of the N805 is 4.8 ohms at 200hz and consequently relatively easy to drive. I have been using my 60 watt tube amps. to drive them very well indeed.
B&W Nautilus 805 loudspeaker Measurements | Stereophile.com
Cheers
Sid

805s is 3.7 Ohms and 805 diamond 3.5 ohms... let me see which speaker i got it confused it with which has a sub 3 ohm.

 

[anm]

Malvai, lot of gyan - now share some pics of how you have set the beauties in your house.