I just checked quickly some comments here -- about average SPL: Add to that average power, some room for higher crest factor than noise (10dB). then add again some dB's for margin and then add dB's for less efficient speakers.
THx-RNMarsh
THx-RNMarsh
So my critique is wrong and the others are correct ..🙂 ok i stand corrected , where can i hear these special horns and does this one measure up ..
http://www.lamaisonduhautparleur.com/kit-aeria-systeme.php
What about noise floor ?
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A.Wayne,
Take most PA horns or even some deluded home builders and use a typical 2" or even some 1.4" compression drivers and you will hear what you are taking about, horn shout, due to the on axis frequency rise matching the cutoff frequency of the horn and very poor polar response. This is much less likely on a 1" exit compression driver and a properly designed waveguide. Some of the newer very short compression drivers are very good at dispersion and with a good horn you would be surprised how much better things can be. We can't go by PA systems, those very often have serious design errors and are made to get loud and you are to correct any of the horn shout with massive eq, basically cut that band from the response curve.
I know Eperando and I highly doubt that he would put up with this type of on axis response or frequency response errors. If there was room to use waveguides and I am not talking the short ones on a dome tweeter I would consider there use in small consumer speakers but you just can't shrink a waveguide to a reasonable size in most instances and physics is physics. Check out the TAD ET-703 and tell me you can detect any horn shout on that device. I am just not sure most people would pay 2.5k$ for a single high frequency device! It is when some try and get down into the midrange to match with a typical 15" driver with large compression drivers and large exit diameters that we are going to agree that they don't sound very nice.
Take most PA horns or even some deluded home builders and use a typical 2" or even some 1.4" compression drivers and you will hear what you are taking about, horn shout, due to the on axis frequency rise matching the cutoff frequency of the horn and very poor polar response. This is much less likely on a 1" exit compression driver and a properly designed waveguide. Some of the newer very short compression drivers are very good at dispersion and with a good horn you would be surprised how much better things can be. We can't go by PA systems, those very often have serious design errors and are made to get loud and you are to correct any of the horn shout with massive eq, basically cut that band from the response curve.
I know Eperando and I highly doubt that he would put up with this type of on axis response or frequency response errors. If there was room to use waveguides and I am not talking the short ones on a dome tweeter I would consider there use in small consumer speakers but you just can't shrink a waveguide to a reasonable size in most instances and physics is physics. Check out the TAD ET-703 and tell me you can detect any horn shout on that device. I am just not sure most people would pay 2.5k$ for a single high frequency device! It is when some try and get down into the midrange to match with a typical 15" driver with large compression drivers and large exit diameters that we are going to agree that they don't sound very nice.
We are almost on the same page now. isnt the TAD a waveguide as oppose to a horn ... ?
I think at this point that horn/waveguide can be interchangeably used. But you can easily mess them up. Having grown up with Altec, JBL, EV, Community and just about everything else I can say that they are a mess most of the time.
The TAD ET-703 is actually a diffraction design, it happens to work well and is very uncommon.
The TAD ET-703 is actually a diffraction design, it happens to work well and is very uncommon.
I thought he meant Bose 802's 😀
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Yeah a quality 1" compression driver on a Good horn or waveguide = 🙂
The problem with 1.4" & over is easily resolved by crossing over to a super tweeter @ say 5kHz - 7kHz. It doesn't do any harm either with 1" 😉 I've designed/built a number of such systems over the years for clubs etc, & if time aligned etc, they sound superb ! 🙂
I was referring to the B&W's
Recommended power is 200-500W.
I have also read that their impedance curcve is very well behaved.
That is for sure. I have both... a playback system and a piano in my living/listening room. The piano is loud without hurting your ears.... peaks. very high average to peak ratio (or crest factor).
THx-RNMarsh
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Reason this instrument was called 'Piano Forte' ?
About horns and linearity, this is the big version of my enclosures:
http://www.esperado.fr/images/perso/mesure.gif
The horn reproduce bandwidth from 600Hz to 20.000. Having a look to the waterfall, it seem difficult to have so few resonances from a conventional cone driver, don't you think ?
Difficult too to get such a bandwidth from a single transductor with all the coherency that procure the lack of crossover in the mediums/treebles range.
Not forgetting that, because the emissive surface of the horn is the same than the bass driver at the crossover frequency, directivity (= energy) is the same there and it cross nicely whatever your position in the room.
Last, an advantage of horns is they excite less the room resonances, and the directivity of this horn (or JMLC ones) is very smooth and progressive.
Massive, build from wood, no internal resonances and a beautiful look.
Again, not any 'donnald Duck or 'shout' effect. Just a very 'fast', analytic and dynamic reproduction i never find with cones or domes.
BTW: it was difficult to find a very good driver at this time. The TAD had an accident, and the JBL we chose had some manufacturing problems, depending of the sample witch obliged-us to measure all of them in the manufacturer place to eliminate bad samples. It was the 16 ohms model JBL 2426.
Really, the bad reputation of horns is not justified when the expansion curves are accurate, the driver is good, and everything build with care. On the contrary, the transparency and absence of coloration is amazing, dynamic behavior impossible to challenge with any other electroacoustic tranducer. You will discover little details in your records that you never noticed before, and each record will sound so different. 3D spacialization is good too, with a lot of space between instruments, and ease of listening and separate each instruments from an other.
Yes, it is expensive, yes it takes time and competency to design, but, at the end, it is worth the prices and the efforts.
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Yes, I goofed with my words. I did mean sensitivity, e.g., 85 dB SPL at 2.83V at 1 meter.
Acoustics is not my strong point, so my comments about the SPL/perceived loudness at the listening position in a typical room are probably off.
My most relevant direct experience with relatively uncompressed music and needed amplifier power was with Rickie Lee Jones "Ghetto of my Mind" on her Flying Cowboys album. The electrically measured crest factor on that one was about 14dB or more.
Playing it at a realistic but not annoying level in a typical-sized hotel room at RMAF showed 250W peaks with 3-way speakers with a sensitivity of about 84dB. Interestingly, the peaks occurred not from bass notes, but rather from snare drum thwacks.
Cheers,
Bob
I would have thought youd stick to a CFA type here too.
Nevertheless it probably uses njm2068 opamps which are not to bad either, that is sound wise. Others will smirk that this opamp is used even in their 5000 $ + amps.
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Im afraid youre wrong.
Youre not supposed to take anything away or let FB connect anywhere, youre supposed to look at the circuit as it is presented. It is essentially composed of two buffers.
Take a look at the attached image. You should be able to find it in your varsity day electronics literature, that is if you did your course after the 90s as before then I dont think the circuit was described.
The two "in" are at high impedance. Is this so hard to see ??? The "A" section can be a CFA or a VFA, it doesnt distract from the classification.
That image is taken from the LM6172 datasheet, a VFA opamp built on CFA properties. I said before, study the datasheet and the patents around it, if you still dont understand. 😉
manso.
I don't agree, sorry. Not two buffers but two parallel symmetric gain stages with criss-crossed feedback, The fact you have resistors connecting the source-node gives the circuit gain. The cross-coupling makes the circuit more resilient to gnd-issues. A brilliant circuit with current feedback.
I don't agree, sorry. Not two buffers but two parallel symmetric gain stages with criss-crossed feedback, The fact you have resistors connecting the source-node gives the circuit gain. The cross-coupling makes the circuit more resilient to gnd-issues. A brilliant circuit with current feedback.
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Fine, we will leave it at that.
It would be interesting to know what J Curl classifies the circuit as.
May i suggest 2 other albums, First one is 'She' of Harry Connic.Jr. with a quite good piano and amazing brass section at realistic level (Pity the voice is too much in front, as usual ;-( .
And the best piano recording i've never heard, 'Sacred' from Don Pullen. There is a 10mn track 'Common ground' in it that i cannot listen without tears in my eyes.
It is an improvisation he made in the studio, right back from the hospital were he was told he had a cancer and his days were shortly numbered.
My mother was a pianist, reason why i was never satisfied by all the recordings of piano i made in my life ? I thought it was impossible. This one brings-you a Steinway right in your room, with everything right: The weight, the noise of the pedals, the hit of the hammer on the chords etc. And the story he tells in this tune is everithing about our own death lived in few minutes: grief, longing, fear, anger, acceptance, peace.
We already know that. He thinks it's a VFA. Does his opinion make it so 😀?
It's indeed funny to note how some contributors around are staunch supporters of CFA's, without even being able to understand and identify one as so
.It's indeed funny to note how some contributors around are staunch supporters of CFA's, without even being able to understand and identify one as so
If you can change the ULGF by changing the feedback resistor does this mean you are dealing with a CFA?
