So who won the great bake off?

[shadders]

The most basic custom driver is obtained by paying the driver manufacturer extra not to put their label on an off-the-shelf driver. The next level is to pay a bit more to put a different label on instead.

Hi,

Thanks for the information - was quite interesting and informative. The costs of the bespoke design does seem rather cheap to the end user.

If it was me, i would peel off the manufacturers label and hand write the my design name on the back of the magnet to keep the costs down. *biggrin*

Regards,

Shadders.

 

[shadders]

Hi,

OK - what does a custom driver mean, indicate or prove ?.

Near standard OEM driver, does sound like a modified driver.

Designed from scratch - they look similar in design - magnet, cone, probably has a voice coil etc. So in essence, specific parameters will have been specified - but what does all this mean ?

Regards,

Shadders.

Sorry?

I've read your post a couple of times and I'm not sure what specific question you're trying to ask here.

Hi,

OK - it seems that you were confirming a statement of another poster.

My text was referring to the designed from scratch statement. The general design of a speaker used is the same, all that can be modified are the parameters of the system, be it voicecoil length, impedance, cone doping to change resonances, magnet design to change sensitivity (if that is what you need to change to improve sensitivity - i am not sure). etc. So, designed from scratch is really specifying specific parameters ?.

I am not sure - hence the question - what does it al mean.

Regards,

Shadders.

A conventional 6.5 inch driver is made up of many components, all of which can be specified separately.

The 'basket' (frame) magnet size, coil diameter, gap size, coil type, cone, etc, etc, can all be specified separately, so it is perfectly possible to build a unique, 'custom' driver out of what are, effectively, stock parts.

If the driver specified in this way is only supplied to one customer, then it is, in effect a custom unit.

For example, if a magnet assembly normally used on a bigger basket is modified to fit a smaller basket then maybe only the fitting bolts need to be relocated, this is then a 'custom' driver. I have no specific knowledge of the AVI driver, but I do know how quality drive units are built and the variations that can be made.

Hi,

Thanks. In essence a custom driver is a variation on existing components.

I had transformers made and they were custom - still roughly the same cost as an off the shelf unit.

Regards,

Shadders.

Within the limits of the tooling available to the manufacturer, that is pretty much what happens.

There are so many possible variations, even using standard components. Alloy magnets tend to be more expensive and more compact, in some setups that might be important, but ferrite is cheaper and more stable over time, there is little, if any advantage by using alloy magnets on cone drivers.

Back in the day, ATC would wind coils by hand for their early dome midrange drivers, numbers were at that time, quite small. We also specified a special version of their 12 in driver as a mid bass driver, others a special 'Long Coil' bass driver, none of these 're-invented the wheel' but produced 'custom designs' for specific applications.

Hi,

Thanks. It seems that custom drivers, or slight variations do not cost much more than the COTS products. I examined cases for a DAC i had designed, and the initial costs were quite high, but once you have even small numbers, the costs were realisticly cheap.

Regards,

Shadders.

 

[hg]

If it was me, i would peel off the manufacturers label and hand write the my design name on the back of the magnet to keep the costs down. *biggrin*

A while ago a German importer was not bothering to peel off the labels of imported Asian drivers and was simply sticking their label over the manufacturers one. There is an obvious risk in doing this if you go big on the markup.

 

[davedotco]

The most basic custom driver is obtained by paying the driver manufacturer extra not to put their label on an off-the-shelf driver. The next level is to pay a bit more to put a different label on instead.

Hi,

Thanks for the information - was quite interesting and informative. The costs of the bespoke design does seem rather cheap to the end user.

If it was me, i would peel off the manufacturers label and hand write the my design name on the back of the magnet to keep the costs down. *biggrin*

Regards,

Shadders.

But not unfair in many cases.

Reminds me of a tale told to me at JBL in the early 70s.

A few years earlier they had a request from Fender for a 15 inch unit for their new guitar cabinet, they said that they had heard good things about our (JBL) D130 driver.

So samples were sent, including a comprehensive spec sheet and application notes. Word came back that although they really liked the unit, they felt the 50 watt power rating was not sufficient for their requirements.

So another batch of samples were send, this time with a new lable proclaimong the unit as the Fender D130F Musical instrument loudspeaker, with a 100watt rating. Fender loved it and bought zillions, well many thousands over a decade or more.

It ws of course the same D130 as was sent in the first place, but the spec sheet and the rest of the paperwork was changed to suit.

Cheating? Not at all, being a proper engineering company their written specs were always precise and accurate. It went like this,

The D130, for hi-fi use as an extended range speaker was rated at 25 watts, full range at 0.5% distortion.

The Pro D130, for use as a general purpose voice and background music system was 50 watts full range at 2% distortion.

The D130F Musical instrument speaker was rated at 100 watts, limited bandwith (to suit the electric guitar of the day), at 10% distortion.

Same product, different spec but all totally correct.

 

[oivavoi10]

Reminds me of a tale told to me at JBL in the early 70s.

A few years earlier they had a request from Fender for a 15 inch unit for their new guitar cabinet, they said that they had heard good things about our (JBL) D130 driver.

So samples were sent, including a comprehensive spec sheet and application notes. Word came back that although they really liked the unit, they felt the 50 watt power rating was not sufficient for their requirements.

So another batch of samples were send, this time with a new lable proclaimong the unit as the Fender D130F Musical instrument loudspeaker, with a 100watt rating. Fender loved it and bought zillions, well many thousands over a decade or more.

It ws of course the same D130 as was sent in the first place, but the spec sheet and the rest of the paperwork was changed to suit.

Cheating? Not at all, being a proper engineering company their written specs were always precise and accurate. It went like this,

The D130, for hi-fi use as an extended range speaker was rated at 25 watts, full range at 0.5% distortion.

The Pro D130, for use as a general purpose voice and background music system was 50 watts full range at 2% distortion.

The D130F Musical instrument speaker was rated at 100 watts, limited bandwith (to suit the electric guitar of the day), at 10% distortion.

Same product, different spec but all totally correct.

Interesting and funny story. Came to think of something my cousin told me. He works in a company that develops technologies and machines for cancer treatment at hospitals. According to him, when selling to Germans, he needed to explain how things actually worked. When selling to Americans, he needed to sound convincing and make lots of promises about the results they could expect (so he had to find things to say which sounded good, but wouldn't backfire on him). When he sold to the Chinese, he needed to make an extremely long list of specifications and functions. They would rather have a machine that could do 15 things than a machine that could do 10 things.

End of off-topic rambling on national stereotypes

 

[shadders]

If it was me, i would peel off the manufacturers label and hand write the my design name on the back of the magnet to keep the costs down. *biggrin*

A while ago a German importer was not bothering to peel off the labels of imported Asian drivers and was simply sticking their label over the manufacturers one. There is an obvious risk in doing this if you go big on the markup.

Hi,

Yes, some people, organisations do amaze me sometimes what they do.

Regards,

Shadders.

 

[shadders]

The most basic custom driver is obtained by paying the driver manufacturer extra not to put their label on an off-the-shelf driver. The next level is to pay a bit more to put a different label on instead.

Hi,

Thanks for the information - was quite interesting and informative. The costs of the bespoke design does seem rather cheap to the end user.

If it was me, i would peel off the manufacturers label and hand write the my design name on the back of the magnet to keep the costs down. *biggrin*

Regards,

Shadders.

But not unfair in many cases.

Reminds me of a tale told to me at JBL in the early 70s.

A few years earlier they had a request from Fender for a 15 inch unit for their new guitar cabinet, they said that they had heard good things about our (JBL) D130 driver.

So samples were sent, including a comprehensive spec sheet and application notes. Word came back that although they really liked the unit, they felt the 50 watt power rating was not sufficient for their requirements.

So another batch of samples were send, this time with a new lable proclaimong the unit as the Fender D130F Musical instrument loudspeaker, with a 100watt rating. Fender loved it and bought zillions, well many thousands over a decade or more.

It ws of course the same D130 as was sent in the first place, but the spec sheet and the rest of the paperwork was changed to suit.

Cheating? Not at all, being a proper engineering company their written specs were always precise and accurate. It went like this,

The D130, for hi-fi use as an extended range speaker was rated at 25 watts, full range at 0.5% distortion.

The Pro D130, for use as a general purpose voice and background music system was 50 watts full range at 2% distortion.

The D130F Musical instrument speaker was rated at 100 watts, limited bandwith (to suit the electric guitar of the day), at 10% distortion.

Same product, different spec but all totally correct.

Hi,

My approach would be to examine the specifications - and the discrepancy would arise - higher power and higher THD.

So, although the same driver - they have provided the correlating data - power and THD.

One could infer, same specification, but the data provided is different, but still correlates.

Regards,

Shadders.

 

[davedotco]

The most basic custom driver is obtained by paying the driver manufacturer extra not to put their label on an off-the-shelf driver. The next level is to pay a bit more to put a different label on instead.

Hi,

Thanks for the information - was quite interesting and informative. The costs of the bespoke design does seem rather cheap to the end user.

If it was me, i would peel off the manufacturers label and hand write the my design name on the back of the magnet to keep the costs down. *biggrin*

Regards,

Shadders.

But not unfair in many cases.

Reminds me of a tale told to me at JBL in the early 70s.

A few years earlier they had a request from Fender for a 15 inch unit for their new guitar cabinet, they said that they had heard good things about our (JBL) D130 driver.

So samples were sent, including a comprehensive spec sheet and application notes. Word came back that although they really liked the unit, they felt the 50 watt power rating was not sufficient for their requirements.

So another batch of samples were send, this time with a new lable proclaimong the unit as the Fender D130F Musical instrument loudspeaker, with a 100watt rating. Fender loved it and bought zillions, well many thousands over a decade or more.

It ws of course the same D130 as was sent in the first place, but the spec sheet and the rest of the paperwork was changed to suit.

Cheating? Not at all, being a proper engineering company their written specs were always precise and accurate. It went like this,

The D130, for hi-fi use as an extended range speaker was rated at 25 watts, full range at 0.5% distortion.

The Pro D130, for use as a general purpose voice and background music system was 50 watts full range at 2% distortion.

The D130F Musical instrument speaker was rated at 100 watts, limited bandwith (to suit the electric guitar of the day), at 10% distortion.

Same product, different spec but all totally correct.

Hi,

My approach would be to examine the specifications - and the discrepancy would arise - higher power and higher THD.

So, although the same driver - they have provided the correlating data - power and THD.

One could infer, same specification, but the data provided is different, but still correlates.

Regards,

Shadders.

The tale illustrates a number of points.

JBL were a serious engineering company in those days and their products sold mostly as components with accurate specifications and application notes carefully detailing under what conditions these specs would be met. JBL puplished other material too, mostly quite technical with some practical help for pro users gleaned from projects and measurements carried out at Northridge.

By contrast with Fender, JBL also supplied drive units for EMI's custom monitor in the late 60s/early 70s, product was shipped to EMI's engineering division in Hayes, next to the vinyl pressing plant. Every single component was checked and measured, the crossover modified to produce EMI's unique monitor, used at, among other places, Abbey Rd around the end of the Beatles era.

It is also rather instructive as to how different specifications can be made to look, in this case the specs were quite accurate, imagine what they might have said if they were written to the same standards as a lot of modern hi-fi equipment?

 

[shadders]

The most basic custom driver is obtained by paying the driver manufacturer extra not to put their label on an off-the-shelf driver. The next level is to pay a bit more to put a different label on instead.

Hi,

Thanks for the information - was quite interesting and informative. The costs of the bespoke design does seem rather cheap to the end user.

If it was me, i would peel off the manufacturers label and hand write the my design name on the back of the magnet to keep the costs down. *biggrin*

Regards,

Shadders.

But not unfair in many cases.

Reminds me of a tale told to me at JBL in the early 70s.

A few years earlier they had a request from Fender for a 15 inch unit for their new guitar cabinet, they said that they had heard good things about our (JBL) D130 driver.

So samples were sent, including a comprehensive spec sheet and application notes. Word came back that although they really liked the unit, they felt the 50 watt power rating was not sufficient for their requirements.

So another batch of samples were send, this time with a new lable proclaimong the unit as the Fender D130F Musical instrument loudspeaker, with a 100watt rating. Fender loved it and bought zillions, well many thousands over a decade or more.

It ws of course the same D130 as was sent in the first place, but the spec sheet and the rest of the paperwork was changed to suit.

Cheating? Not at all, being a proper engineering company their written specs were always precise and accurate. It went like this,

The D130, for hi-fi use as an extended range speaker was rated at 25 watts, full range at 0.5% distortion.

The Pro D130, for use as a general purpose voice and background music system was 50 watts full range at 2% distortion.

The D130F Musical instrument speaker was rated at 100 watts, limited bandwith (to suit the electric guitar of the day), at 10% distortion.

Same product, different spec but all totally correct.

Hi,

My approach would be to examine the specifications - and the discrepancy would arise - higher power and higher THD.

So, although the same driver - they have provided the correlating data - power and THD.

One could infer, same specification, but the data provided is different, but still correlates.

Regards,

Shadders.

The tale illustrates a number of points.

JBL were a serious engineering company in those days and their products sold mostly as components with accurate specifications and application notes carefully detailing under what conditions these specs would be met. JBL puplished other material too, mostly quite technical with some practical help for pro users gleaned from projects and measurements carried out at Northridge.

By contrast with Fender, JBL also supplied drive units for EMI's custom monitor in the late 60s/early 70s, product was shipped to EMI's engineering division in Hayes, next to the vinyl pressing plant. Every single component was checked and measured, the crossover modified to produce EMI's unique monitor, used at, among other places, Abbey Rd around the end of the Beatles era.

It is also rather instructive as to how different specifications can be made to look, in this case the specs were quite accurate, imagine what they might have said if they were written to the same standards as a lot of modern hi-fi equipment?

Hi,

Yes - what is never provided is the THD for a speaker - as far as i know.

Hifi News provide THD measurements for speakers - but how this correlates to driver and crossover distortion is unknown. I would expect crossover distortion to be a much smaller proportion for the THD measurement against the driver and cabinet contributions.

Unless manufacturers provide measurements, we can only guess. Unless other forum posters can provide this information ?

Thanks and regards,

Shadders.

 

[Blacksabbath25]

Dali .... OPTICON 8 Frequency Range (+/-3 dB) [Hz] 38 - 32,000 Sensitivity (2,83 V/1 m) [dB] 88.0 Nominal Impedance [ohms] 4 Maximum SPL [dB] 112 Recommended Amplifier Power [W] 40 - 300 Crossover Frequency [Hz] 390 / 2,300 / 14,000 Crossover Principle 3 + ½-way Hybrid tweeter module, Super high freq. driver, Quantity 1 x 17 x 45 mm Hybrid tweeter module, Super high freq. driver, Diaphragm type Ribbon Hybrid tweeter module, High frequency driver, Quantity 1 x 28 mm Hybrid tweeter module, High frequency driver Diaphragm type Soft Textile Dome Midrange driver, Quantity 1 x 6 1/2" Midrange driver, Diaphragm type Wood Fibre Cone Low frequency driver, Quantity 2 x 8" Low frequency driver, Diaphragm type Wood Fibre Cone Enclosure type Bass Reflex Bass Reflex Tuning Frequency [Hz] 29.5 Connection Input Bi-Wiring Magnetic Shielding No Recommended Placement Floor Recommended Distance From Wall [cm] 30 - 150 Dimensions With Base (HxWxD) [mm] 1140 x 241 x 450 Weight [kg] 34.8

dali do if you go on there website this is the spec on my speakers but Dali also make active speakers too

 

[shadders]

Dali .... OPTICON 8 Frequency Range (+/-3 dB) [Hz] 38 - 32,000 Sensitivity (2,83 V/1 m) [dB] 88.0 Nominal Impedance [ohms] 4 Maximum SPL [dB] 112 Recommended Amplifier Power [W] 40 - 300 Crossover Frequency [Hz] 390 / 2,300 / 14,000 Crossover Principle 3 + ½-way Hybrid tweeter module, Super high freq. driver, Quantity 1 x 17 x 45 mm Hybrid tweeter module, Super high freq. driver, Diaphragm type Ribbon Hybrid tweeter module, High frequency driver, Quantity 1 x 28 mm Hybrid tweeter module, High frequency driver Diaphragm type Soft Textile Dome Midrange driver, Quantity 1 x 6 1/2" Midrange driver, Diaphragm type Wood Fibre Cone Low frequency driver, Quantity 2 x 8" Low frequency driver, Diaphragm type Wood Fibre Cone Enclosure type Bass Reflex Bass Reflex Tuning Frequency [Hz] 29.5 Connection Input Bi-Wiring Magnetic Shielding No Recommended Placement Floor Recommended Distance From Wall [cm] 30 - 150 Dimensions With Base (HxWxD) [mm] 1140 x 241 x 450 Weight [kg] 34.8

dali do if you go on there website this is the spec on my speakers but Dali also make active speakers too

Hi,

Thanks. I checked the website - no statement of the THD of the speakers. If they provide active as well as passive speakers, then this could be used as a comparison.

Regards,

Shadders.

 

[davedotco]

Dali .... OPTICON 8 Frequency Range (+/-3 dB) [Hz] 38 - 32,000 Sensitivity (2,83 V/1 m) [dB] 88.0 Nominal Impedance [ohms] 4 Maximum SPL [dB] 112 Recommended Amplifier Power [W] 40 - 300 Crossover Frequency [Hz] 390 / 2,300 / 14,000 Crossover Principle 3 + ½-way Hybrid tweeter module, Super high freq. driver, Quantity 1 x 17 x 45 mm Hybrid tweeter module, Super high freq. driver, Diaphragm type Ribbon Hybrid tweeter module, High frequency driver, Quantity 1 x 28 mm Hybrid tweeter module, High frequency driver Diaphragm type Soft Textile Dome Midrange driver, Quantity 1 x 6 1/2" Midrange driver, Diaphragm type Wood Fibre Cone Low frequency driver, Quantity 2 x 8" Low frequency driver, Diaphragm type Wood Fibre Cone Enclosure type Bass Reflex Bass Reflex Tuning Frequency [Hz] 29.5 Connection Input Bi-Wiring Magnetic Shielding No Recommended Placement Floor Recommended Distance From Wall [cm] 30 - 150 Dimensions With Base (HxWxD) [mm] 1140 x 241 x 450 Weight [kg] 34.8

dali do if you go on there website this is the spec on my speakers but Dali also make active speakers too

Hi,

Thanks. I checked the website - no statement of the THD of the speakers. If they provide active as well as passive speakers, then this could be used as a comparison.

Regards,

Shadders.

Also 2.83 volts is 1 watt into 8 ohms, so rather more than 1 watt into 4 ohms (nominal impedance) so the sinsitivity figures are hyped, neither distortion nor power levels are quoted with regard to frequency response and half a dozen other things.

As it happens I have a lot of time for Dali, I think they make some very decent, honest products, the Zensor 1 is still my preferred sub £200 speaker. However even these specs give little idea of how the speaker will perform in general terms.

Dali do make an active speaker, but there is no passive equivilent.