Alas, this hasn't been made for nearly 3 decades and spares are Unobtainium. It had a lot of ju ju which we pioneered but we had other speakers with the same ju ju which, while doing well, didn't perform as well as this little box in DBLTs. The cone material, which I specified, is no longer available.
I could pontificate about why it sounded so good but it would be from the wrong orifice 😊
About the only thing I'm sure of replicating is the LF performance as we were pioneers in the early use of TS bla bla. Only a couple of recording engineers realised it had limited LF but they still liked the bass.
A couple of my friends are trying to corner the market for this little gem so I beg your pardon for not revealing its identity.
Have a look at http://www.troelsgravesen.dk/Wharfedale.htm about E70. 'Bat Ears' ****** is one of the best ears I've ever tested. You can probably work out who the visually challenged ***** ******** is too.
Hi cumbb, I can't agree on the above and the answer is all in that your "almost" (the bold is mine), in my view.
Not only that, even if it seemed true it would only prove one thing: that listening tests are unreliable and lead to false results because no one in the world is able to withstand the pressure of having to give an urged opinion on what they are listening to and also because in those cases the auditory system adapts to the situation and becomes less and less reliable, in my view of things.
My opinion is that listening tests are useless.
Please note that I say this from the dispassionate point of view of an amateur like me, but of course opinions can be very different depending on the role that one has in the audio world.
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hi i agree Sometimes i cant control bad jokes Actually i am very interested about small speakers that can cover lets say the band from 300Hz up
usually many have low sensitivity unfortunately
Completing the band will be very easy If i had a 3 ways i would take out the mid and high and place them on a baffle or a separate box
Hi then how do you know that a speaker is good ? the options are just two 1) by measuring it 2) by listening it
@ginetto61
I've designed some transistor AB class power amplifier from 20W to 300W per channel and had studied them since the 90's. An AMP is an electrical device and it's not that difficult or too expensive to build it to perform very close to ideal performance. Frequency response DC to 100KHz totally flat. impedance output to miliohms, THD around 0,01%, S/N neglectable and other parameters. And here, all parameters are measurable - they are electrical parameters.
In my country, where everything is expensive, the cost of building a good 2x100W amp will be less than US$200,00.
On the other hand, if we consider a loudspeaker, it is a fully imperfect world. Even high quality and expensive loudspeaker will not be flat at all, THD around 0,5 to 1% is considered ok, minor or major resonances will be everywhere, difractions, on axis and off axis response totally different by several dB's, same thing if you consider near field and far field listening place - totally different response. Not to mention when you combine the loudspeaker with the room. When you do, frequency response below 200Hz will have wild peaks and notches by 5, 10, 15dB!!
Comparing amplifiers, you see differences of less than 0.1%, but comparing loudspeakers you may see 5, 10, 15dB differences - a small bookshelf will not play 30Hz.
When you have 2 devices in series they sum their performance: amp + speaker. Considering just good AB class amps, If you change the amp, it is expected that you won't be able to notice a difference.
Let's take the THD. Even if an amp has THD of 0.01% and the other has THD of 0.02%, when summed to the speaker THD, you will compare a system that has 1.01% with another that has 1.02%. If you consider frequency response, there is no way of hearing a difference between well designed class AB amps - there is no difficult in building an amp that is perfect flat.
Conclusion: focus must be on the speaker. In this forum there is a huge amount of information about how to build a good speaker (simulation tools for the box and crossover etc). In my case, I don't follow the modern trend of 2-way small speakers plus subwoofer. I prefer 3-way full range speakers (from 25Hz to 20KHz). With a 8" or 10" woofer and a 50 to 60-liter box, you can have a very nice response. In my country, the cost of such 3-way speaker will be around US$350,00 for the pair, if you build them yourself, of course.
I've designed some transistor AB class power amplifier from 20W to 300W per channel and had studied them since the 90's. An AMP is an electrical device and it's not that difficult or too expensive to build it to perform very close to ideal performance. Frequency response DC to 100KHz totally flat. impedance output to miliohms, THD around 0,01%, S/N neglectable and other parameters. And here, all parameters are measurable - they are electrical parameters.
In my country, where everything is expensive, the cost of building a good 2x100W amp will be less than US$200,00.
On the other hand, if we consider a loudspeaker, it is a fully imperfect world. Even high quality and expensive loudspeaker will not be flat at all, THD around 0,5 to 1% is considered ok, minor or major resonances will be everywhere, difractions, on axis and off axis response totally different by several dB's, same thing if you consider near field and far field listening place - totally different response. Not to mention when you combine the loudspeaker with the room. When you do, frequency response below 200Hz will have wild peaks and notches by 5, 10, 15dB!!
Comparing amplifiers, you see differences of less than 0.1%, but comparing loudspeakers you may see 5, 10, 15dB differences - a small bookshelf will not play 30Hz.
When you have 2 devices in series they sum their performance: amp + speaker. Considering just good AB class amps, If you change the amp, it is expected that you won't be able to notice a difference.
Let's take the THD. Even if an amp has THD of 0.01% and the other has THD of 0.02%, when summed to the speaker THD, you will compare a system that has 1.01% with another that has 1.02%. If you consider frequency response, there is no way of hearing a difference between well designed class AB amps - there is no difficult in building an amp that is perfect flat.
Conclusion: focus must be on the speaker. In this forum there is a huge amount of information about how to build a good speaker (simulation tools for the box and crossover etc). In my case, I don't follow the modern trend of 2-way small speakers plus subwoofer. I prefer 3-way full range speakers (from 25Hz to 20KHz). With a 8" or 10" woofer and a 50 to 60-liter box, you can have a very nice response. In my country, the cost of such 3-way speaker will be around US$350,00 for the pair, if you build them yourself, of course.
Yeaaaa, at the age of 14 I also flattened my nose at smooth frequency responses, power specifications and distortion values until physics began to differentiate and complexify my view of world - which doesn't mean that I begrudge anyone - or the majority - staying 14 forever;-)
An AB amplifier is actually two amplifiers consisting of different sounding parts that amplify the half-waves separately and with different sounds. A single analog complementary transistor stage is enough, and it sounds discolored, dirty, gray, broken, slowed down, small... - compared to analog concepts that do not amplify the entire signal separately. With AB, the greatest loudspeaker effort no longer helps to eliminate this relative error)-;
An AB amplifier is actually two amplifiers consisting of different sounding parts that amplify the half-waves separately and with different sounds. A single analog complementary transistor stage is enough, and it sounds discolored, dirty, gray, broken, slowed down, small... - compared to analog concepts that do not amplify the entire signal separately. With AB, the greatest loudspeaker effort no longer helps to eliminate this relative error)-;
Sure. Just remarking that the traditional class AB amplifier made of at least 3 stages is a class A voltage amplifier (first and second stage) until the signal reaches the third stage (here class AB), where there is no longer voltage amplification, but just current amplification (emitter follower in bipolar or source follower in mosfets).
There is a misunderstanding, since I had already expressed here my opinions on this more than once and I thought I could have shortened it. 😊
However, given that I'm not a manufacturer or a seller or a dealer and then I cannot know that sector of the market from their points of view and furthermore I cannot even know if, how and possibly why DBLT are useful for them, I believe that DBLTs are useless for the purposes of those who want to buy a new device to insert in their sisyems since in my view they will first have to insert that device into their systems and then listen to it in order to judge it with their own ears.
Only then, in my opinion, they will know if they likes it or not, regardless of the results of the DBLTs.
So I can confirm that I completely agree with both of you about the above quoted comments of yours, but not with cumbb's statement that I quoted before about small speakers. 🙂
Hi thank you for the very kind and valuable advice
I have now a direction to follow
I have always been fascinated by electronics more than speakers I can't explain why
But it's clearly better to invest time and resources where they can provide a better sound
I have now the tool for performing basic measurements on drivers and speakers
I also like to mix and match drivers and cabinets
I bought some speakers with damaged box and vice versa
First thing now to recover from bronchitis
@ginetto61
Cool! I also started with electronics by 1988 totally focussed on class AB amplifiers.
Along the journey, I found out that what really matters is the loudspeaker as long as you use a minimum good amplifier.
If you have an analog calibrated microphone, pré-amp and a sound card you are good to go in order to build a very pleasant loudspeaker and not spending much. I'm using the following softwares/procedures:
1. WinISD for simulating the box itself such as volume, tuning etc for the response below 200Hz more or less.
2. EDGE for baffle simulation - it helps to position the speakers on the front panel (baffle) in order to minimize difraction
3. REW for getting the impedance/phase and frequency response / phase of each speaker already installed in the box - Make sure to take timed measurements, which I learnt here. You make some arrangements with your sound card in order to allow REW to measure the distance of each speaker. You have to keep the box and mic exactly on the same position to get all the individual measurements of each speaker. So, all the measurements will have a time aligment for further phase sync in XSim.
4. XSim for crossover simulation. You upload the impedance and frequency response files got from REW. So you will design your crossover based on ACTUAL measurements - It works like a dream!
You can achieve incredible results with this procedure. I've built / redesing some 3-way speakers and the results were fantastic.
Thanks to the members of DIYAudio which helped me some months ago. You can see my post, if you want.
Cool! I also started with electronics by 1988 totally focussed on class AB amplifiers.
Along the journey, I found out that what really matters is the loudspeaker as long as you use a minimum good amplifier.
If you have an analog calibrated microphone, pré-amp and a sound card you are good to go in order to build a very pleasant loudspeaker and not spending much. I'm using the following softwares/procedures:
1. WinISD for simulating the box itself such as volume, tuning etc for the response below 200Hz more or less.
2. EDGE for baffle simulation - it helps to position the speakers on the front panel (baffle) in order to minimize difraction
3. REW for getting the impedance/phase and frequency response / phase of each speaker already installed in the box - Make sure to take timed measurements, which I learnt here. You make some arrangements with your sound card in order to allow REW to measure the distance of each speaker. You have to keep the box and mic exactly on the same position to get all the individual measurements of each speaker. So, all the measurements will have a time aligment for further phase sync in XSim.
4. XSim for crossover simulation. You upload the impedance and frequency response files got from REW. So you will design your crossover based on ACTUAL measurements - It works like a dream!
You can achieve incredible results with this procedure. I've built / redesing some 3-way speakers and the results were fantastic.
Thanks to the members of DIYAudio which helped me some months ago. You can see my post, if you want.
Thank you very much again I had issues with REW using my soundcard And because i hate challenges i decided to buy something more ready to go
I have now the usb and the Android Dayton calibrated mics and the Dayton dats v3
i can measure TS parameters and i have already discovered some interesting things
Sad things actually like the fact that drivers can age and change their properties Usually for the worst
there are a lot of vintage parts around but i have to buy before being able to test them
My dream speaker is very basic A 3 way with mid and tweeter on top of a bass box Maybe even arranged on a open baffle like in the dq10
these speakers will be always a reference for me If only i could understand their exotic crossover
i have never seen one more complicated
I have now the usb and the Android Dayton calibrated mics and the Dayton dats v3
i can measure TS parameters and i have already discovered some interesting things
Sad things actually like the fact that drivers can age and change their properties Usually for the worst
there are a lot of vintage parts around but i have to buy before being able to test them
My dream speaker is very basic A 3 way with mid and tweeter on top of a bass box Maybe even arranged on a open baffle like in the dq10
these speakers will be always a reference for me If only i could understand their exotic crossover
i have never seen one more complicated