I didn't do that at any point. You been studying the complete works of Arnie Kruger? He used to use that line all the time. But I will let it drop. I had thought you were a seeker of truth, but I was wrong.
I don't see it. The original bbc research paper I linked showed flat on axis response, albeit with some off axis dip. If you compare with the wireless world article Harwood talks about ON axis response dips. There is no evidence anyone in bbc research dept put in an on axis dip or that the monitors were designed for off axis listening. If I have missed something happy to be corrected, but so far zero had evidence of a bbc dip by design.
Q: If the total ESR rises vs freq due to proxy or eddy or due to other effects (skin), would that mean the ESL is reduced by the phase angle being affected (no longer 90 degrees) and resultant is an effective lowering of L (thinking vectors here). ?
THx-RNMarsh
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remind dear billy shruv, or whomever he is, that IF he blocks me he's not going to see any of my posts.
the fellow, dear billy, is really short of temper and thin of skin, imo.
He mentions Arny Kruger? I mention Lord Stewart Pinkerton - of which and whom ol' bill reminds me of... but Pinkerton did have somewhat better gear, even back in the day...
...sorry for this minor diatribe.
_-_-
the fellow, dear billy, is really short of temper and thin of skin, imo.
He mentions Arny Kruger? I mention Lord Stewart Pinkerton - of which and whom ol' bill reminds me of... but Pinkerton did have somewhat better gear, even back in the day...
...sorry for this minor diatribe.
_-_-
There is a bit more to the BBC midrange issue. If this hasn't been posted before... BBC LS3/5, LS5/8, LS5/9, LS5/12A monitors - Page 4
That covers a bit on some of the models. What is missing from all of this is the design of the studios in which the monitors were used. When you have the classic booth with acoustic tile on all the walls on axis frequency response will be quite different than power response in a more reflective room.
Another issue would be the measurement microphones of the day were 1" types which would have had a high frequency rise due to increased coupling as you approached a quarter wavelength.
There was the need for durability when a user would do something stupid. Either drop a stylus or fast forward a tape while the head lifters were defeated.
Then we could also throw in loudspeaker mounting and how that wall bounce changes the on axis frequency response.
Now who will be the first to acknowledge they don't know the difference between on axis frequency response and power response?
That covers a bit on some of the models. What is missing from all of this is the design of the studios in which the monitors were used. When you have the classic booth with acoustic tile on all the walls on axis frequency response will be quite different than power response in a more reflective room.
Another issue would be the measurement microphones of the day were 1" types which would have had a high frequency rise due to increased coupling as you approached a quarter wavelength.
There was the need for durability when a user would do something stupid. Either drop a stylus or fast forward a tape while the head lifters were defeated.
Then we could also throw in loudspeaker mounting and how that wall bounce changes the on axis frequency response.
Now who will be the first to acknowledge they don't know the difference between on axis frequency response and power response?
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Sorry, this is more Internet lore. The design report is available online. It was designed for a flat response on axis.
As I mentioned in an earlier thread where this came up: the Britdip is very pronounced, but you have to look at the off axis behavior.
BBC LS3/5a loudspeaker 1989 Measurements | Stereophile.com
The speakers are relatively flat on axis (although not to modern standards), but the power response shows a huge dip in the 2-3kHz region.
Internet lore speaks truth.
A lot of speakers have poor off axis behaviour. I am not sure that can be pinned on british design other than the propensity of 2-ways vs say, a 3-way. This is certainly an interesting area for discussion, but is a fork off from the point being discussed ref the wireless world article where Harwood clearly talks about a dip in on-axis response.
So are we discussing on axis response or power response when taring the british speaker industry?
(aside, not found a good reference for how important power response is in a well damped near or midfield studio environment as the LS series were designed for. If anyone has such a reference I would be grateful).
So are we discussing on axis response or power response when taring the british speaker industry?
(aside, not found a good reference for how important power response is in a well damped near or midfield studio environment as the LS series were designed for. If anyone has such a reference I would be grateful).
And to throw the cat amongst the pigeons.
BBC LS3/5a loudspeaker Stirling Measurements | Stereophile.com
BBC LS3/5a loudspeaker Stirling Measurements | Stereophile.com
The model itself is an ideal inductance in series with an ideal resistance. As such, the inductive component is always the response which is 90 degrees out, and the resistive is that which is in phase.
If you think in terms of phaser notation, recall that the vectors add at 90 degrees to each other, so the resistive component does not reduce the inductive component.
What may be deceiving you is the interaction complexity. The eddy currents created are 90 degrees out of phase with the dB/dt (bdot), and the field created by the eddy's are another 90 out. This means that the field created by eddies is 180 from the inducing magfield, this causes cancellation of magfield. Reduction of magfield is a lowering of magnetic energy stored, which is by definition, what inductance is.
The meter reports on that total field storage, and reports as well on what it sees as energy loss. It does not care if the loss is at drive frequency or any harmonics of drive, it just integrates the total energy that does not return to the meter.
In that regard, the meter will not provide an independent measure of proximity losses which are at double frequency (the primary loss mechanism when resistance is modulated by the absolute value of the rate of magfield change). So it will not distinguish internal crowding loss within an inductor winding from external eddy losses of nearby conductive objects.
John
I´m sorry, but you did. You insisted that i´ve said that all or many BBC speakers (means developed by the BBC) had the BBC dip included. http://www.diyaudio.com/forums/lounge/146693-john-curls-blowtorch-preamplifier-part-ii-8740.html#post4812028
Although Harwood wrote about "on-axis response" i think it is clear that he is describing effects from the "on-listening-axis response" .
I am not sure, but afair the general praxis in the BBC rooms was to place the speakers backside parallel to the front wall without toe in.
I've had good luck when I can get a card to work full duplex in ASIO. ARTA for instance will play/record in perfect sync all day long with several very cheap USB devices. CoolEdit 2000 worked great under XP but now I can't get two instances to play/record together anymore after Win7.
If you are running or would like to run multiple instances of CoolEdit, I'm not sure why you would use CoolEdit 2000 at this point in time. For example, Reaper is cheap, pretty full featured as compared to the best professional recording programs, and can be run indefinitely in demo mode with only a brief nag screen while remaining otherwise uncrippled. For running multiple sound cards simultaneously, n-Track studio used to be able to run any number, of any type, all at once, although I haven't looked at it lately.
It's just what you get used to. I generally don't use any musician oriented features I normally only do one track and use it as a measurement instrument on amplifiers etc. If I google, "reaper ASIO" I see the usual flock of folks having issues, that would be me. Right now I'm moving to ARTA and Python.
We just went through one of these issues a few weeks ago. Lots of people didn't realize that there is no way to get Audacity to record 24 bits, no warning just 8 "0" LSB's (no ASIO support) .
I read about this back when the speaker was produced. I dont even know if there was an Internet then. The dip in the mid-range power response was left in as a sort of Fletcher-M comp. It sounded best (flat) that way by consensus listening (BBC) and so it remained.
THx-RNMarsh
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Ok, but if you google Cubase and ASIO you also see people sometimes having problems. And Cubase is a Steinberg product, the company that created the ASIO standard in the first place. Usually, the problem is with the drivers supplied by sound card manufacturers.
That being said, I use ARTA as well. But it's not the right tool for everything I need.
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