Tweeter replacement advice please

[scrambledegs]

Hi there

I'm new to the forum. Thanks in advance for checking my post and (hopefully) helping me out

I have a pair of NAD 804 loudspeakers and i've buggered the tweeter in one of them with some buggy audio production software sending a burst of digital noise through them which burnt out one of the coils . I can't find any info on those speakers or components at all, but the tweeters seem to match these tymphany/peerless tweeters in both part number and look: www . tymphany . com / 811815. I've copied the specs below to make it easier for you as i cant post a link.

Is anyone able to recommend a readily available similarly specced tweeter to replace the one in each unit, will I run into crossover compatibility problems if i do this, or am i better off taking the tweeter for repair (wherever that might be...)?

I'm not terribly au fait with the electronics in a loudspeaker (particularly crossovers) so be nice, however i'm a quick learner and keen to make this work! If you are just able to recommend some decent brands and a good online store i'm quite happy to look for the right product myself. If you need any more info from me i'll do my best, and I'm in the UK if this makes a difference for ordering parts.

Thanks very much,
Ferg

Specs
Electrical Data
Nominal Impedance Zn 8 ohm
Minimum Impedance Zmin 5.9 ohm
Maximum Impedance Zo 30.5 ohm
DC Resistance Re 5.5 ohm
Voice Coil Inductance Le 0.1 mH
TS Parameters
Resonance Frequency fs 860 Hz
Mechanical Q factor QMS 4.31
Electrical Q factor QES 0.94
Total Q factor Qts 0.77
Force Factor Bl 3.5 Tm
Mechanical Resistance Rms 0.48 Kg/s
Moving Mass Mms 0.038 g
Suspension Compliance Cms 0.09 mm/N
Effective cone diameter D 2.8 cm
Effective Piston Area sd 6.2 cm^2
Sensitivity 2.83V/1m 92 dB

Power Handling
Long-term Max Power IEC 18.3 100 W
Voice Coil and Magnet Parameters
Voice Coil Diameter 26 mm
Voice Coil Height 1.8 mm
Voice Coil Layers 2
Height of the Gap 2.5 mm
Flux density of gap 1.5 mWb
Total Useful Flux 0.3 mWb
Diameter of Magnet 72 mm
Height of Magnet 15 mm
Weight of Magnet 0.24 Kg
Frequency

 

[Swerd]

I have a pair of NAD 804 loudspeakers and i've buggered the tweeter in one of them with some buggy audio production software sending a burst of digital noise through them which burnt out one of the coils . I can't find any info on those speakers or components at all, but the tweeters seem to match these tymphany/peerless tweeters in both part number and look: www . tymphany . com / 811815. I've copied the specs below to make it easier for you as i cant post a link.

Is anyone able to recommend a readily available similarly specced tweeter to replace the one in each unit, will I run into crossover compatibility problems if i do this, or am i better off taking the tweeter for repair (wherever that might be...)?

You didn't say it directly, but the Peerless 811815 is no longer available. I assume that is your problem.

Contact Madisound or Parts Express, and explain your problem to them. Both companies have tech people available online or by phone who may know of a suitable replacement tweeter. It probably will not be a simple drop-in replacement, you might have to modify the crossover. If you are lucky, it may be as simple as adding or changing a resistor or two for the new tweeter. If this is the case, replace both tweeters.

If it requires changes to the crossover frequency or the slope of the crossover curve, you might be better off trying to repair the tweeter. Again ask Madisound & Parts Express if they can name a repair service that can replace or wind a new voice coil.

Good luck.

 

[TLS Guy]

Hi there

I'm new to the forum. Thanks in advance for checking my post and (hopefully) helping me out

I have a pair of NAD 804 loudspeakers and i've buggered the tweeter in one of them with some buggy audio production software sending a burst of digital noise through them which burnt out one of the coils . I can't find any info on those speakers or components at all, but the tweeters seem to match these tymphany/peerless tweeters in both part number and look: www . tymphany . com / 811815. I've copied the specs below to make it easier for you as i cant post a link.

Is anyone able to recommend a readily available similarly specced tweeter to replace the one in each unit, will I run into crossover compatibility problems if i do this, or am i better off taking the tweeter for repair (wherever that might be...)?

I'm not terribly au fait with the electronics in a loudspeaker (particularly crossovers) so be nice, however i'm a quick learner and keen to make this work! If you are just able to recommend some decent brands and a good online store i'm quite happy to look for the right product myself. If you need any more info from me i'll do my best, and I'm in the UK if this makes a difference for ordering parts.

Thanks very much,
Ferg

Specs
Electrical Data
Nominal Impedance Zn 8 ohm
Minimum Impedance Zmin 5.9 ohm
Maximum Impedance Zo 30.5 ohm
DC Resistance Re 5.5 ohm
Voice Coil Inductance Le 0.1 mH
TS Parameters
Resonance Frequency fs 860 Hz
Mechanical Q factor QMS 4.31
Electrical Q factor QES 0.94
Total Q factor Qts 0.77
Force Factor Bl 3.5 Tm
Mechanical Resistance Rms 0.48 Kg/s
Moving Mass Mms 0.038 g
Suspension Compliance Cms 0.09 mm/N
Effective cone diameter D 2.8 cm
Effective Piston Area sd 6.2 cm^2
Sensitivity 2.83V/1m 92 dB

Power Handling
Long-term Max Power IEC 18.3 100 W
Voice Coil and Magnet Parameters
Voice Coil Diameter 26 mm
Voice Coil Height 1.8 mm
Voice Coil Layers 2
Height of the Gap 2.5 mm
Flux density of gap 1.5 mWb
Total Useful Flux 0.3 mWb
Diameter of Magnet 72 mm
Height of Magnet 15 mm
Weight of Magnet 0.24 Kg
Frequency

It might be your lucky day.

Your best bet is to try and get your tweeter repaired. Contact Orange county speakers. They have a huge store of parts.

If not this is the closest you will get.

The impedance curve is a little different. The free air resonance lower, but that does not matter, it can not be higher. The good news is that the acoustic data is similar for both.

I have been through a lot of tweeters, and that is the only one I see close enough for a drop in replacement. You might well have to modify the cabinet. You will need two tweeters.

The best solution though is to get your tweeter repaired. The speakers will sound a little different with different drivers.

 

[highfigh]

That tweeter has a user-replaceable diaphragm, if it's really the part in the original post. Madisound is a likely source, or contact Tymphany directly.

 

[TLS Guy]

That tweeter has a user-replaceable diaphragm, if it's really the part in the original post. Madisound is a likely source, or contact Tymphany directly.

I know, but I can't find a source for the diaphragm anywhere. They used to be readily available. That whole Tymphani set up has been a disaster, typical of modern corporate nonsense. A bunch of Wallys have come in who know nothing and have destroyed two good firms and are on their way to destroying a third.

 

[TLS Guy]

It might be your lucky day.

Your best bet is to try and get your tweeter repaired. Contact Orange county speakers. They have a huge store of parts.

If not this is the closest you will get.

The impedance curve is a little different. The free air resonance lower, but that does not matter, it can not be higher. The good news is that the acoustic data is similar for both.

I have been through a lot of tweeters, and that is the only one I see close enough for a drop in replacement. You might well have to modify the cabinet. You will need two tweeters.

The best solution though is to get your tweeter repaired. The speakers will sound a little different with different drivers.

Sorry, I missed the fact you are in the UK. Wilmslow Audio are about the only decent source of quality drivers in the UK.

They have the tweeter I selected, and they no longer carry the replacement parts for your tweeter. NAD speakers have never been available in the US, and those speakers are not even in the NAD archive. If they are old, they are probably not worth fixing. You would be better off putting the costs to new and better speakers.

If you can find what the woofer is and can copy the circuit of the crossover then I would have more options for you, but it will mean redesigning and rebuilding the crossovers.

If you live in Kent or close, you probably know what I mean by a bunch of Wallys. Do you know how old that epithet is and how it got started?

If you are any where near the Medway towns I might be able to help you. I'm going to be in the Medway towns, in a month. I arrive four weeks from today. I have pretty good facilities where I will be workshop wise. My software comes with me in my laptop. My father usually wants something, even though he is nearly 90! However I'm going to the Isle of Man on Sept 14, I already have booked passage on the Ben me Cree from the port of Heysham. I'm leaving the Isle of Man on Sept 17, but will likely drop by to see my sister in law and her husband in the Malvens (Kingsland Herefordshire) on the way back. I will be at Medway (Frindsbury) by Friday evening.



I'm off to see my best friend from school. He was best man at our wedding. This is how he describes his appointment in the Isle of Man, a post he retired from last October, when he says he finally hung up his wig. He held the post for seven years.

"Like a medieval bishop, I held several offices in plurality: Clerk of Tynwald, Secretary of the House of Keys, Counsel to the Speaker and Registrar of Members' Interests! The job is a curious combination of law, administration, research and agony uncle, in this tiny but ancient parliament."

As I sure you know the Tynwald is a very ancient institution. The House of Keys is the worlds longest Parliament, having sat without interruption for 1000 years.

I seem to have a couple of people in the political arena now. My brother Paul Carter, rules Kent with an iron hand!