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Latest edition of Hi-Fi Choice
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Have a review of floor standers and the winner was the Cambridge Audio based on BMR with woofer - I assume it uses a passive crossover - they said it sounded good
I haven't read that test yet, but normally the Hi-fi Choice group tests are conducted with an un-sighted panel. The opinions are thus entirely subjective, but also likely to be unbiased.
I'm not a press apologist, but having had dealings with many of the UK magazines and the reviewers, I feel many of the bias accusations to seldom be justified. There is one magazine I would not have offered products to, for precisely the reasons you state - My then editor attended their awards evening, the gist of the main presentation being that cash = prizes, so it is out there, but I'll let you guess who. Or What.
When I search Ebay with "BMR 20 speaker" the only nice thing that I see is this:
Chevrolet : Chevelle chevelle | eBay
Does anyone have the ebay link? I cant find it.
On topic:
I think that the Cambride isnt a real High End speaker... Probably still very nice but I guess Dereks' CIA is from a higher level. (It should be an improvement even over a multi-thousands$ Manger system, and those sound nice!).
thing that I see is this:Chevrolet : Chevelle chevelle | eBay
Does anyone have the ebay link? I cant find it.
On topic:
I think that the Cambride isnt a real High End speaker... Probably still very nice but I guess Dereks' CIA is from a higher level. (It should be an improvement even over a multi-thousands$ Manger system, and those sound nice!).
I have probably joined too late on this thread. However, looking at the last few comments, they seem to suggest that Cambridge Audio do not use any passive components for the well respected BMR designs. They do have a 6db order series capacitor (Electrolytic, Treble could be improved with a 1uf bypass polyprop cap) to increase the power ratings. Also, there is an LCR (Ferrite inductor, maybe air core could further improve midband clarity) filter to equalise the upper mid/treble response.
As to whether DSP sounds better than the few passive components is another thing. I guess with DSP you can achieve a more flat response?
As to whether DSP sounds better than the few passive components is another thing. I guess with DSP you can achieve a more flat response?
You can get pretty much the same results with either but it is far more easy with DSP. Building a good passive crossover Is hard. Even more hard if the driver isn't naturally flat like the bmr.
Like for like comparison - active Vs passive
Hi all,
Just reading the recent posts here and thinking about the active Vs passive options. I have done a lot of comparisons with BMR's / conventional drivers / Manger drivers / passive crossovers and active crossovers.....Here are my thoughts:
The advantages of active over passive with conventional speakers are well documented and many companies ( ATC, PMC, Linn, Naim etc) who manufacture high end monitors offer the option of upgrading from passive to active.
All these advantages apply to the BMR as well.
The extra significance and advantage of using a DSP based active crossover is that, if implemented correctly, it preserves the time domain / phase purity of the BMR. All passive crossovers smear the phase / time domain to some degree....The more components the worse the effect.
Capacitors and inductors are "frequency dependent energy storage devices"
and the bigger they are, the more you use, the worse the tolerance differences become and the worse the phase / time smearing becomes.
This effect is more obvious on BMR's than conventional push pull drivers because the push pull drivers exhibit far more time domain distortion that the crossover.
Replace the conventional driver with a BMR and then the remaining passive crossover flaws become very obvious...
Like a huge spot on the face of a woman with otherwise perfect skin.....You wouldn't notice it if she had severe acne....but if her skin is otherwise perfect the one huge spot is a bummer!
Lastly, cost....Good DIY power amps are very low cost.
Also DAC's and DSP are such great value now....DIYINHK, Mini DSP, plus some great DIY projects on this site allow you build a very good system at low cost.
Hope this helps and all the best
Derek.
Hi all,
Just reading the recent posts here and thinking about the active Vs passive options. I have done a lot of comparisons with BMR's / conventional drivers / Manger drivers / passive crossovers and active crossovers.....Here are my thoughts:
The advantages of active over passive with conventional speakers are well documented and many companies ( ATC, PMC, Linn, Naim etc) who manufacture high end monitors offer the option of upgrading from passive to active.
All these advantages apply to the BMR as well.
The extra significance and advantage of using a DSP based active crossover is that, if implemented correctly, it preserves the time domain / phase purity of the BMR. All passive crossovers smear the phase / time domain to some degree....The more components the worse the effect.
Capacitors and inductors are "frequency dependent energy storage devices"
and the bigger they are, the more you use, the worse the tolerance differences become and the worse the phase / time smearing becomes.
This effect is more obvious on BMR's than conventional push pull drivers because the push pull drivers exhibit far more time domain distortion that the crossover.
Replace the conventional driver with a BMR and then the remaining passive crossover flaws become very obvious...
Like a huge spot on the face of a woman with otherwise perfect skin.....You wouldn't notice it if she had severe acne....but if her skin is otherwise perfect the one huge spot is a bummer!
Lastly, cost....Good DIY power amps are very low cost.
Also DAC's and DSP are such great value now....DIYINHK, Mini DSP, plus some great DIY projects on this site allow you build a very good system at low cost.
Hope this helps and all the best
Derek.
Interesting words, the same words that applied to the original Yamaha's NS10s found in nearly all major recording studios. They didn't have an exceptionally flat frequency response, but the Time domain was where it won over the rest of the studio monitors. However, the qualities were associated with the construction materials of the Mid/Bass cone rather than the crossover.
Most good quality studio monitors nowadays are active to achieve these good results.
Makes me wonder why the BMRs never made it to the recording studios as near field monitors?
Most good quality studio monitors nowadays are active to achieve these good results.
Makes me wonder why the BMRs never made it to the recording studios as near field monitors?
Hi Delphiplasma,
Well said, the the Yamaha's strenghs in the time domain outweighed its bright side frequency response errors.
We have been testing out a range of BMR studio monitors with great success and will be launching a couple of models in the Spring.
Are you involved in studio production?
Cheers
Derek.
Just a quick modification for the Cambridge audio minx mini10, remove the 3.8 microfarad capacitor. This gets rid of the bright upper treble and provides a perfectly flat response within 3db between 250hz to 10khz. Use the capacitor to bypass the series electrolytic capacitor. The sound quality is very well balanced.
Hi Derek,
I still don't understand the problem of passive crossover with BMR.
Time domain distortion ...??
Passive components have a storage effect, which causes delays...etc. Having a direct connection to an amplifier is the best connection. DSP is an active device with no large storage components and therefore better qualities within the time domain making for better musicality. The speaker cabinets can also affect this property.
I have added dampening to the mini 10 and the frequency response is flat within 2db between 250Hz - 15KHz. The undamped mini10 cabinets exhibit resonance which feedback into the driver. Dampening the walls help with the benefits of thin walled cabinets; less energy storage.
I have added dampening to the mini 10 and the frequency response is flat within 2db between 250Hz - 15KHz. The undamped mini10 cabinets exhibit resonance which feedback into the driver. Dampening the walls help with the benefits of thin walled cabinets; less energy storage.