Hello all!
I'm new to the forum. I've been snooping around for a while and there is some wicked geekery to be had! I'm looking forward to getting stuck in.
I am looking for a pair of replacement super-tweeters for my beautiful LEAK 3090s. I am told the original Isodynamic tweeters cant be fixed (although I couldn't even get anyone to look at them, so there is possibly hope in the future). I am a music producer and I use them as main monitors for referencing mixes so a flat response is pretty important (the LEAKs do +-3db 35hz-26khz), although I'm not looking for super harsh/revealing "monitor" speakers, as I have another pair for that. I also use them for general listening. I'm powering them with an old Soundmaster VF200 dual mono power amp, I can find any info on it but to my ears it sounds wicked and it has plenty of power.
Photo:
Specs:
I originally replaced them with Monacor RBT-95 SQs, which are ok (especially for the price!) and incidentally fit perfectly when wedged under the faceplate. However, it seems they were a little underpowered for a speaker of this size and recently the right hand side has had an intermittent distortion problem, with some volume discrepancies. I haven't swapped them to check it is the driver so I could be wrong, but to me it sounds like a toasted tweeter.
So I'm looking for a ribbon or similar, with enough power to keep up with the LEAKs and I would love to get some recommendations. My budget is around £40-80 each (I'm a student!) but please tell me if that is stupidly low.
Many thanks,
Louis
I'm new to the forum. I've been snooping around for a while and there is some wicked geekery to be had! I'm looking forward to getting stuck in.
I am looking for a pair of replacement super-tweeters for my beautiful LEAK 3090s. I am told the original Isodynamic tweeters cant be fixed (although I couldn't even get anyone to look at them, so there is possibly hope in the future). I am a music producer and I use them as main monitors for referencing mixes so a flat response is pretty important (the LEAKs do +-3db 35hz-26khz), although I'm not looking for super harsh/revealing "monitor" speakers, as I have another pair for that. I also use them for general listening. I'm powering them with an old Soundmaster VF200 dual mono power amp, I can find any info on it but to my ears it sounds wicked and it has plenty of power.
Photo:
An externally hosted image should be here but it was not working when we last tested it.
Specs:
I originally replaced them with Monacor RBT-95 SQs, which are ok (especially for the price!) and incidentally fit perfectly when wedged under the faceplate. However, it seems they were a little underpowered for a speaker of this size and recently the right hand side has had an intermittent distortion problem, with some volume discrepancies. I haven't swapped them to check it is the driver so I could be wrong, but to me it sounds like a toasted tweeter.
So I'm looking for a ribbon or similar, with enough power to keep up with the LEAKs and I would love to get some recommendations. My budget is around £40-80 each (I'm a student!) but please tell me if that is stupidly low.
Many thanks,
Louis
Maybe others experience may help you.
http://www.diyaudio.com/forums/multi-way/133211-isodynamic-whats.html
Maybe more consistent/quality
FT7RP - Fostex ribbon tweeter
http://www.fostexinternational.com/docs/speaker_components/pdf/ft7rprev.pdf
http://www.diyaudio.com/forums/multi-way/133211-isodynamic-whats.html
Maybe more consistent/quality
FT7RP - Fostex ribbon tweeter
http://www.fostexinternational.com/docs/speaker_components/pdf/ft7rprev.pdf
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Thanks for the reply Inductor. Some interesting info on the technology behind these, although due to the complicated nature it doesn't look hopeful for repair. There's something about ribbon tweeters (especially the old LEAK ones) that are just really nice to listen to. You get ZERO listening fatigue but at the same time a beautiful airy sound.
The Fostex look perfect, although I'm having trouble finding somewhere that will sell them in the UK at a reasonable price. I'll have a hunt on ebay.
I thought of something that could have contributed to the problem. This amplifier makes a HORRIFIC sound when you turn it off. It does one big pop, and then lots of smaller pops tapering off into a final distorted squelch. I never really thought about it (stupidly) but that cant be good for my speakers! Could it be that this was what fried my tweeter? The noise does seem exaggerated on that side.
The Fostex look perfect, although I'm having trouble finding somewhere that will sell them in the UK at a reasonable price. I'll have a hunt on ebay.
I thought of something that could have contributed to the problem. This amplifier makes a HORRIFIC sound when you turn it off. It does one big pop, and then lots of smaller pops tapering off into a final distorted squelch. I never really thought about it (stupidly) but that cant be good for my speakers! Could it be that this was what fried my tweeter? The noise does seem exaggerated on that side.
Wicked site. Do you know what kind of power rating I should be looking at? I don't have the original spec for tweeter power. The whole speakers are rated at 100watts RMS.
Leak 3090 Tweeters
I also have a pair of Leak 3090s; fortunately my tweeters are OK at present. The Leak Isodynamic tweeters are not ribbon tweeters as such; they are moving coil drivers. The flat voice coil is etched onto a 25 micron diaphragm. These were patented by Leak; the idea was later taken up by a few other manufacturers ie EMIT for some NEAT models, but these were circular. It has seen a bit of a revival recently.
The Leak design gives a very smooth response (as resonances are well below the operating range) together with good dispersion due to it’s vertical slit . These superseded a mylar dome tweeter used in the previous 2075 models. Even some modern domes can sound ‘peaky’ & beam noticeably in comparison.
These speakers have a high efficiency, but they just don’t work with amplifiers with small power supplies; the 4 way crossover is complex & the inductor feeding the 15” bass driver looks bigger than some transformers...I am using a 300+300W Bryston 4BSST power amp which not only grips these spkrs but also can play them very, very quietly. Tweeters can easily be blown by clipping a low power amp whereby square waves feed full power high frequency distortion into the tweeters.
Wilmslow Audio sell a Fostex ribbon tweeter (93dB, 80W) which is £105 each. Integrating ribbon tweeters with moving coil drivers is notoriously difficult & I would go for a dome/inverted dome, that fits physically but also has an extended response up to ~ 40kHz. This would help with the smoothness as well as bringing rewards with newer SACD/DVDA, hi res streaming formats.
These speakers were originally expensive as were the drive units (I believe that replacement Leak tweeters were ~ £70 more than 20 years ago), so I can understand your disappointment with the Monacor ribbons. Unfortunately this means that replacements need to be very carefully considered & I believe that it is well worth fitting high quality tweeters to these unique spkrs.
Dougal
I also have a pair of Leak 3090s; fortunately my tweeters are OK at present. The Leak Isodynamic tweeters are not ribbon tweeters as such; they are moving coil drivers. The flat voice coil is etched onto a 25 micron diaphragm. These were patented by Leak; the idea was later taken up by a few other manufacturers ie EMIT for some NEAT models, but these were circular. It has seen a bit of a revival recently.
The Leak design gives a very smooth response (as resonances are well below the operating range) together with good dispersion due to it’s vertical slit . These superseded a mylar dome tweeter used in the previous 2075 models. Even some modern domes can sound ‘peaky’ & beam noticeably in comparison.
These speakers have a high efficiency, but they just don’t work with amplifiers with small power supplies; the 4 way crossover is complex & the inductor feeding the 15” bass driver looks bigger than some transformers...I am using a 300+300W Bryston 4BSST power amp which not only grips these spkrs but also can play them very, very quietly. Tweeters can easily be blown by clipping a low power amp whereby square waves feed full power high frequency distortion into the tweeters.
Wilmslow Audio sell a Fostex ribbon tweeter (93dB, 80W) which is £105 each. Integrating ribbon tweeters with moving coil drivers is notoriously difficult & I would go for a dome/inverted dome, that fits physically but also has an extended response up to ~ 40kHz. This would help with the smoothness as well as bringing rewards with newer SACD/DVDA, hi res streaming formats.
These speakers were originally expensive as were the drive units (I believe that replacement Leak tweeters were ~ £70 more than 20 years ago), so I can understand your disappointment with the Monacor ribbons. Unfortunately this means that replacements need to be very carefully considered & I believe that it is well worth fitting high quality tweeters to these unique spkrs.
Dougal
Question
Hi, I have checked the details of your replacement Monacor tweeter & this has a claimed efficiency of 98dB this is very high; if you are not getting much output then there could be another problem:
1. I had a problem with the attenuator pots being intermittent; spraying De-oxit anti-oxidant in them cured the problem resulting in more output (WD40 would probably be as good). DO NOT spray anything containing corrosives/solvents anywhere near the polystyrene drivers as they will MELT ! Exercising (turning the knobs) the pots regularly makes a big difference.
2. Capacitors age & may fail; I have considered replacing all of mine but it is quite a big job as there are several. I would like to replace them all with non-polarised types but the correct values are not all available. Capacitors deteriorate faster in hot environments, can be damaged by high voltage spikes & ultimately may leak DC or go open cct. But they can sometimes recover from spike damage.
3. The most likely cause of your failure is indeed as you suspect the noises your amp makes on switch on/off. I have witnessed a hi-fi dealer destroy a customer's tweeters by connecting/disconnecting cables with everything powered up - there was a loud fizzing pop & the result was burnt out tweeters (in a pair of £4.5K floor standers).
Sounds like a daft question but have you checked your original tweeter for being open cct with a meter ?
Cheers, Dougal
Hi, I have checked the details of your replacement Monacor tweeter & this has a claimed efficiency of 98dB this is very high; if you are not getting much output then there could be another problem:
1. I had a problem with the attenuator pots being intermittent; spraying De-oxit anti-oxidant in them cured the problem resulting in more output (WD40 would probably be as good). DO NOT spray anything containing corrosives/solvents anywhere near the polystyrene drivers as they will MELT ! Exercising (turning the knobs) the pots regularly makes a big difference.
2. Capacitors age & may fail; I have considered replacing all of mine but it is quite a big job as there are several. I would like to replace them all with non-polarised types but the correct values are not all available. Capacitors deteriorate faster in hot environments, can be damaged by high voltage spikes & ultimately may leak DC or go open cct. But they can sometimes recover from spike damage.
3. The most likely cause of your failure is indeed as you suspect the noises your amp makes on switch on/off. I have witnessed a hi-fi dealer destroy a customer's tweeters by connecting/disconnecting cables with everything powered up - there was a loud fizzing pop & the result was burnt out tweeters (in a pair of £4.5K floor standers).
Sounds like a daft question but have you checked your original tweeter for being open cct with a meter ?
Cheers, Dougal
Hello all!
I completely forgot about this post. I was searching around for a more suitable amp for my speakers now that I have a bit of cash and thought I'd look on here!
Just to update you on my tweeter issues, I think much of the problem was due to the tweeters being only a few days old. I gave them a good running in and after a while the distortion disappeared and they became much smoother and less harsh. I couldn't be happier! I'm sure they could be improved with a higher frequency response but in searching for a new amp I've found most amps are only 20-20 anyway.
Dougallh, I'm very jealous of your working tweeters (and killer amp, I bet yours sound amazing!). It's good to know someone else is rocking the LEAKS. I wonder if you might be able to suggest a power amp that might be more within my price range? (£200-300) When I'm rich and famous I'll spend some money restoring the crossovers and parts but for now I just cant afford it and I wouldn't trust someone to do it on the cheap!
All the best,
L
I completely forgot about this post. I was searching around for a more suitable amp for my speakers now that I have a bit of cash and thought I'd look on here!
Just to update you on my tweeter issues, I think much of the problem was due to the tweeters being only a few days old. I gave them a good running in and after a while the distortion disappeared and they became much smoother and less harsh. I couldn't be happier! I'm sure they could be improved with a higher frequency response but in searching for a new amp I've found most amps are only 20-20 anyway.
Dougallh, I'm very jealous of your working tweeters (and killer amp, I bet yours sound amazing!). It's good to know someone else is rocking the LEAKS. I wonder if you might be able to suggest a power amp that might be more within my price range? (£200-300) When I'm rich and famous I'll spend some money restoring the crossovers and parts but for now I just cant afford it and I wouldn't trust someone to do it on the cheap!
All the best,
L
Incredible Leak 3090's
I used a quad 405 with my first pair before they got stolen, and now I am on my second pair I use another Quad 405!
Seems to be a marriage made in heaven.
I know it's an old post, but you might still be wondering what works well with these monsters.
I'm looking for a spare pair, or parts to keep mine going as long as I last, and if I find a source of the right tweeters I will let you know. There is a guy on ebay who keeps listing a pair but he wants silly money for them..
Cheers, Steve C.
I used a quad 405 with my first pair before they got stolen, and now I am on my second pair I use another Quad 405!
Seems to be a marriage made in heaven.
I know it's an old post, but you might still be wondering what works well with these monsters.
I'm looking for a spare pair, or parts to keep mine going as long as I last, and if I find a source of the right tweeters I will let you know. There is a guy on ebay who keeps listing a pair but he wants silly money for them..
Cheers, Steve C.
Leak 3090 capacitors
Replacing the non-polarized electrolytics in the Leak 3090 crossover with film capacitors makes a major improvement in the sound. I also found when I changed the capacitors in my 3090s that some of them were well outside of the labeled values and tolerance. If I recall correctly some of the capacitors which appeared to be labeled as 5% tolerance were more than 10% off of nominal value. This was when my 3090s were a few years old. If you have 3090s that have never had the capacitors upgraded, you should strongly consider it even if you can't afford film capacitors.
Replacing the non-polarized electrolytics in the Leak 3090 crossover with film capacitors makes a major improvement in the sound. I also found when I changed the capacitors in my 3090s that some of them were well outside of the labeled values and tolerance. If I recall correctly some of the capacitors which appeared to be labeled as 5% tolerance were more than 10% off of nominal value. This was when my 3090s were a few years old. If you have 3090s that have never had the capacitors upgraded, you should strongly consider it even if you can't afford film capacitors.
Hey guys!
Just an update (and a bit of a thread revival - I'm not on the internet much these days!). I managed to find a mint pair of original ribbon tweeters for my LEAKs for £50. They sound SO much better than the Monocor pair I was using before. They even have the black foam still attached, although it crumbles to the touch (I'm mildly worried that this might work it's way into the tweeter - any thoughts?). I've also just bought a Quad 520f (I actually bought a pair of them for £250). I haven't picked them up but I'm hoping they're in good condition as described, apparently they've been used in a HMV store for most of their life so it doesn't sound like they've been abused much.
I have to ask, how is it possible to steal a pair of speakers this large?!?!?!
Just an update (and a bit of a thread revival - I'm not on the internet much these days!). I managed to find a mint pair of original ribbon tweeters for my LEAKs for £50. They sound SO much better than the Monocor pair I was using before. They even have the black foam still attached, although it crumbles to the touch (I'm mildly worried that this might work it's way into the tweeter - any thoughts?). I've also just bought a Quad 520f (I actually bought a pair of them for £250). I haven't picked them up but I'm hoping they're in good condition as described, apparently they've been used in a HMV store for most of their life so it doesn't sound like they've been abused much.
I have to ask, how is it possible to steal a pair of speakers this large?!?!?!
LEAK 3090 Crossover Caps
Hi Retate,
I've been desperate to do this for a while but I got completely lost what with the lack of information available on the speakers. It looks like a fairly simple soldering job as the circuit board is fairly chunky. It would be truly amazing if you could provide me with a list of capacitor values needed and a recommendation on what to buy! (bearing in mind my electronics experience only consists of a couple of maplins DIY kits and soldering countless XLR cables)
I have a feeling the caps on my crossovers have degraded somewhat, I've noticed that the left speaker takes a lot more power to balance the other, I originally thought this was the amp but since I've tried other amps the problem persists. Could old caps cause this problem?
Thanks,
L
Hi Retate,
I've been desperate to do this for a while but I got completely lost what with the lack of information available on the speakers. It looks like a fairly simple soldering job as the circuit board is fairly chunky. It would be truly amazing if you could provide me with a list of capacitor values needed and a recommendation on what to buy! (bearing in mind my electronics experience only consists of a couple of maplins DIY kits and soldering countless XLR cables)
I have a feeling the caps on my crossovers have degraded somewhat, I've noticed that the left speaker takes a lot more power to balance the other, I originally thought this was the amp but since I've tried other amps the problem persists. Could old caps cause this problem?
Thanks,
L
Hi,
I see you bought QUAD 520s so I thought I bud in here if I may since I've got one of those.
Basically it is a really nice amp and IMO probably the best current-dumper made by QUAD. In essence it is a 606 with one pair of output transistors missing. In return the 520f was blessed with a huge power supply, much bigger than the one used in the 606.
It sounds nice but not as controlled and transparent as the MC2 Audio amps I use now.
The main drawback is the complete lack of any protection circuitry so it will pop a bit when switching on or off. When you switch it off it will remain operational until the PSU caps drain, finishing off with a very quiet click.
I used it as a treble amp for active Tannoys for some time and the pop was not a problem but I wouldn't use it on active ribbons but with a passive crossover you should have a fair bit of protection anyway.
PS: £250 for a pair is a pretty good deal these days!
I see you bought QUAD 520s so I thought I bud in here if I may since I've got one of those.
Basically it is a really nice amp and IMO probably the best current-dumper made by QUAD. In essence it is a 606 with one pair of output transistors missing. In return the 520f was blessed with a huge power supply, much bigger than the one used in the 606.
It sounds nice but not as controlled and transparent as the MC2 Audio amps I use now.
The main drawback is the complete lack of any protection circuitry so it will pop a bit when switching on or off. When you switch it off it will remain operational until the PSU caps drain, finishing off with a very quiet click.
I used it as a treble amp for active Tannoys for some time and the pop was not a problem but I wouldn't use it on active ribbons but with a passive crossover you should have a fair bit of protection anyway.
PS: £250 for a pair is a pretty good deal these days!
Ah! Thanks for the warning! I'm still using the Studiomaster Mosfet 1000 until my Quad is delivered, which doesn't pop but does like to do a horrific sine sweep when you turn it off (I dread to think what this is doing to my speakers)
So just to clarify, does the passive crossover have it's form of protection circuit? Also, might it be safe to turn the amp on before connecting the Speakon outputs? I've heard they're fairly safe to hotplug but I don't know how the amp would react to running without any load.
So just to clarify, does the passive crossover have it's form of protection circuit? Also, might it be safe to turn the amp on before connecting the Speakon outputs? I've heard they're fairly safe to hotplug but I don't know how the amp would react to running without any load.
From what I can tell your Leak speakers are 4way passives so all lower frequency components of the pop will be blocked from getting to the tweeter by the crossover.
You could also turn down the level control on them.
Better still just turn down the 520s level controls before switching on and off.
The annoying thing is that they have no markings or detents and since the amp is quite sensitive (0.5V input will drive to full power) you'll likely to need some attenuation there.
I don't think you'll have problem, at worst a little inconvenience.
From your description of the other amp (forgot what it was) the QUAD is nowhere near as bad, it doesn't howl after switching off either. If you switch it of with music playing it just fades down to a barely audible click. And that is on the compression driver of my Tannoys.
You could also turn down the level control on them.
Better still just turn down the 520s level controls before switching on and off.
The annoying thing is that they have no markings or detents and since the amp is quite sensitive (0.5V input will drive to full power) you'll likely to need some attenuation there.
I don't think you'll have problem, at worst a little inconvenience.
From your description of the other amp (forgot what it was) the QUAD is nowhere near as bad, it doesn't howl after switching off either. If you switch it of with music playing it just fades down to a barely audible click. And that is on the compression driver of my Tannoys.
Ah, that makes sense. They've done pretty well in terms of reliability anyway, I use them for mixing (they're not ideal for this, but they're pretty flat) and there's always the odd accidental feedback/random crazy noises involved, not to mention uncompressed audio isn't very kind to speakers. I'm hoping to buy some proper monitors in the future so these can retire to being hi-fi speakers and occasional mix reference.
Yes, I've been making do with the output control on my soundcard (Focusrite Saffire Pro 40) but it means I have to run vinyl via USB so a new pre-amp is on my shopping list. I started a thread here about it.
I can provide you a PDF file that includes the notes and a crossover schematic documenting the mods that I made to my Leak 3090s, however it exceeds the size of file I can upload. The notes are handwritten because they were generated in 1982 and 1983 before I had my first home computer system. I would expect most of the capacitors in your crossovers are out of tolerance and some are degraded or worse. In addition to the capacitors I had planned at one time to upgrade the inductors and power resistors, but my 3090s became secondary speakers so I never completed those changes. If you can PM me a direct email address, and information on what size of attachments you can receive I will forward you additional Leak 3090 information.
Hi, I am now @ the stage when I would like to upgrade my 3090 speakers. Do you still have the Xover info please ?
For anyone elses info:
I managed to acquire a spare set of isodynamic tweeters (they were also used in the last Rank Wharfedale Teesdale SP & Dovedale SP. Note that the upper midrange perforated driver in those models is not the same - looks it, but the 3090 one has a larger magnet.
Cheers
For anyone elses info:
I managed to acquire a spare set of isodynamic tweeters (they were also used in the last Rank Wharfedale Teesdale SP & Dovedale SP. Note that the upper midrange perforated driver in those models is not the same - looks it, but the 3090 one has a larger magnet.
Cheers