That foamed adhesive tape around the wires will eventually turn into a nice tarred mess. Some of the grossest repairs I've ever done used this junk. I prefer the cloth tape any day.
Good stuff. Solid construction. Taking a look at the effects of capacitors across rectifiers would make for a cool video. You've got some nice AC sources and loads and what not, plus some EMC probes if I recall. It would be interesting to see how much of a difference it actually makes, particularly if the output is already buffered with multiple capacitor values. I haven't looked into it deeply, but I would expect the capacitors to also create a vulnerability by allowing high frequency noise on the input to pass into the unit? It would make more sense if there was at least a common mode choke before the rectifier in that case. Wouldn't capacitors across rectifiers just lowpass filter the switching transients leaving some low frequencies intact? Would RC snubbers make more sense? Is any of it worth it from a measurable/practical standpoint (audiophile fluff aside)? I'd be grateful to hear some reasoning from experienced engineers; thanks in advance.
Hmm, yes, this would be interesting. Harder to translate that into what difference it makes in audible speaker noise etc, but might be able to see something with some probing.
those caps are probably parallel to diodes to reduce switching noise (which can be in several Mhz, because of diode recovery time and capacitance) not to reduce high freqency coming from trafo or mains I hope Dave can test diode recovery noise on his fancy pancy scopes, compare regular diodes, soft-recovery diodes, fast diodes, schotky, under serious load, no load etc
I've read another explanation around these capacitors. They are creating a path of constant impedance for some stray RF currents flowing through capacitance between the power transformer windings. Without these capacitors, the impedance is modulated (bigger when AC power voltage is near to zero because all diodes are closed) and the RF finds some pn junctions in a most unexpected place to get rectified and creates hum. When the RF current is not modulated with these 100Hz impedance pulses then the effect of RF injection is less noticeable. (But probably this is more relevant for AM broadcast receivers).
Ohhh yeaaahhh... I used to build custom speakers professionally, the die cast alloy rigidity gives a considerable boost in performance to the woofer. Back in 1996 the highest dB record was a truck enclosures made of solid steel plates and concrete!! There are some fancy premium speakers made of polished concrete (must be a pain for international air shipping $$$) haha
if you want damping metal, why not cast iron? dirt cheap and has better damping qualities on its own than any other stock metal. there's a reason precision machines are still made of cast iron to this day.
Drkastenbrot, cabinet flex cancels out the driver resulting in lower efficiency and that nasty “hollow sound” resonance. Basically the sides of the enclosure become an out of phase driver working against the real driver itself...very bad passive radiators essentially. I remember guys bragging about how they could bounce quarters off their subwoofer enclosure. Once they learned that was all wasted energy and then installed reinforcements to minimize the flexing.... much higher output and sound quality. Much tighter bass.
Check Genelec 8000 series (8020A (or B) for example) focals basically copied all the design features from those but made them cheaper in China to get more money (they are approximately equal in price, but Genelec speakers are engineered and built in Finland). Everything from Aluminium cast case to heatsink design, connector placement, dip switches and the lot... ok, they use that fancy inverted dome thingy, but basically a Genelec ripoff ;D 8000-series was launched in 2005, focal came along at around 2011-ish :)
Yes Genelec are nice and have great design, but have to say I recon they copied ATC SCM20's I think thats what they were, (30Kg each!) I seem to remember installing them in late 90's but not as nice looking and really top end, superb bass exelent wide soundstage and clear but not harsh top end streets ahead of most other things we sold at the time.
@@markhaskins8212 I tried to find some models with cast aluminium cabinets but SCM20 itself doesn't really give me much results... hmmh... maybe some other model? I'm interested in seeing where these ideas come from, I thought that ATC only makes HiFi-spkears but maybe not...
I love audio electronics! A amplifier with two TDA2030 was my technician's course final project. 20 Watts sounds AWESOME in a room. I made two box with good two way car speakers and made my own monitor! obviously it's not a focal, but making the electronics and acoustic study works great!
Agreed, the foam tape turns to muck and you're half right. The adhesive on the AC plug and all of the connectors is not only to keep an air tight seal but mainly kill noise because of airflow. Small holes in the connectors will cause squeaking while the woofer is flexing.
You should have a teardown on a Bang & Olufsen 6000 speaker at some point. The amount of sound that they can produce with the drivers they use is unreal, especially when you see what's inside! :)
Hello, I recently just got into the whole electronics diy hobby and I've been watching countless hours of videos. Everyone seems to say that right angle connections on a pcb are bad practice but then when you step away from YT, most forums state it's all lies and they are fine to use. I personally don't like the look of right angles so won't be using them but I'm truly interested in whether or not they're bad practice/what the negatives - positives are for using them.
They are bad practice mostly because they are ugly. They can still be "acid traps" at fine trace width, but not a major issue these days. Also, still an issue with fast controlled impedance traces.
Nice tear down again. I just got a used pair last week and found out, once at home, that the input switch in the back in wired in reverse (i.e. -10db is actually +4db and +4 is -10). I was wondering if it is a manufacture mistake or if it could be because someone serviced them and plugged it wrong. But since both monitors are behaving the same, I reckon it is from the manufacture. Have you seen any weird things on yours?
Surprised you didn't mention the green wires on the back of the mains connector. The end of their insulation ended just where the insulation from the connector started, so you could see part of the conductor when the wire was bent over. I guess if that's the earth ground it's not a hazard, but it does make the wire more likely to break of they are moved around much (though I guess these speakers don't need to be opened very often).
How are they holding up? I would love a follow up video with another tear down as their was concern that the foam tape would become sludge over time... considering used cms65s.
I have a pair of genelec 8030a's. They have a similiar design but it's more refined i think. I love how they sound. And they are not manufactured in china but finland thats also where i live lol.
Hi there I KNOW this is an old video, but I have a question :) I've owned a pair of CMS-65 for maaaany years and one of them is humming when turned on (even though it is not connected to a sound source) - so, this is transformer hum, I'm guessing. The question: Do you think that it will be an "easy operation" to open up the speaker and fix the transformer hum? Tighten it down? I really like the speakers a lot and been working with them professionally for years, so I "know their sound" and do not wish to part with them - but the hum on one of them is driving me CRAZY these days :) Hope you can help and point me in the right direction! Thank you for the video!! All the best Kenneth from Denmark
I would think the metal case would cause echo which is why wood is normally used for speaker cases. Metal casing and weight does give the feel of quality.
It can cause strong internal reflections above the 'pressure zone' where the wavelength of sound is small enough to exist inside the enclosure. Not a lot of acoustic wadding in there either.. but not much space for more! A bit of damping on the inside panels might not go amiss.
Another big advantage of the casing is magnetic shielding. Had a pair of JBL LSR 25 and it was a similar design. Not 100% sure but I think the LSR 25 were the first near field monitors using that kind of casing. The magnetic shielding was nice when used near CRT's.
@@TheSergeiFranco I think the magnets have a separate shield (I am sure the 5inch woofer of the JBL LSR25P has a shield) and the casing acts as a faraday cage (for EMI).
The alloy die cast does nothing to shield magnetically, but the woofer has that extra magnet glued onto the back to cancel out the far magnetic field of the whole ferrite assembly. Probably done so the toroid is not saturating and also so the mains hum does not become audible on the speaker, though that is also helped by the steel cup with the open end away from the magnet assembly. Hardly anybody uses a CRT any more, so the only reason the extra magnet is there still is that it is needed for hum reduction.
@@SeanBZA Not for static or slow changing magnetic fields but it still is a faraday cage. The LSR25P I had was a design from 1999 if I am not mistaken and it was mainly CRT at that time. I had the first pair here in Belgium (worked for JBL Benelux distributor at that time) and they have been sitting next to a CRT for years.
I’d fully expect those to be streets ahead of the KRKs in terms of sound quality. The KRKs might have a little more low end but it’s not exactly the tightest low end. Focal speakers can be a little on the bright side but I think those have a little bit of adjustment.
EEVblog I haven’t heard the particular model you have there but Ive heard other Focal monitors and seven KRK models. The KRKs have always sounded woolly/boomy and opaque by comparison. Adam make some lovely monitors if you change/upgrade again but those Focals should serve you well. They’re physically smaller which is a win for me when they’re sharing desk space.
Would be sweet to see a teardown of ADAM A5X:s; they happen to be my favorite mid-tier nearfields of all time. But it's not like I'm going to open up my own pair, I'd probably ruin them :)
so, not finding too much on the hate for these caps, as some posters said, could be that these caps are just right for the specific use. there isnt too much on the forum about hate for these caps, ut i do hear it from you often. just wondering why.
Hi i have a question, You mentioned they have a slight humm? I have logitech Z10 speakers but they don't humm at all. So i was wondering: why studio monitors humm?
@Jamie Fletcher i tested your theory, and almost lost my ear pressing it against the twitter but still no hiss or humm(while playing music at its lowest)
@@sysierius If you have CD-quality 16bit audio, you can have maximum theoretical dynamic range (the difference between the lowest and loudest signal) of ~96dB, Genelec 8020A (old model already... we're at D-revision already) produces at around >=95dB SPL @ 1m... a pair produces at around 104dB SPL @ 1m. And for all intents and purposes the hiss should always be below the minimum SPL you're able to reproduce, meaning that If you turn them all the way up, you can produce a sound pressures from ~4-5dB SPL all the way up to 104ish dB SPL... which is like a front row in a rock concert, that's why there's hiss, because there would be no reason to have noise figure that's lower than lowest SPL you can produce at maximum volume. And since that hiss is above the treshold of hearing (above 0dB) you're able to hear it... I doubt you would ever hear that under any reasonable program material The masking effect is very real and i raise a hat if you can make out a 2dB SLP signal under ~65dB SPL music playing :) Of course newer models have increased that range quite a bit from both ends... but regardless.
I have a buddy who designs DACs. Says that sometimes he'll use what seem like budget, cheesy caps or resistors or whatever because they have an extremely specific profile they use during tuning and voicing. While it PROBABLY was a cost-cutting maneuver, Focal could be using those Yihcon caps because the speakers sounded better with them.
As long as the capacitors are not in series/parallel with the signal path and power supply is well designed and regulated, those main filter caps should have zero effect on the sound. They should be as good quality as possible with long life and low ESR...
I've got a pair of KRK G3 RP6's. I saw focals offerings when I purchased mine. People have bashed me for not buying the Yamahas. I think my KRK's are very good and have both LF and HF adjusters. They are very low interference volume as well as loud enough for my studio useage. Got mine for £120 each. I also purchased a 8s2 KRK subwoofer for £250 and this completed my studio setup. I produce EDM, Dance and trance music. I also produce rock, metal, ballads and other piano works and these are excellent for all these genres. I've got focals in my car for my 7.1 setup which is excellent.
Surprised to see decades old analog technology in the amp, it could be 1998, TL op amps and TDA power amp, not digital, not class D, is this still state of the art in audio?
About "isolation mats": they are useless. Ethan Winer did measurements on those and the effect is: exactly like moving the speaker up by the isolation pad thickness. If height is compensated: whomp whomp whomp, diddlysquat nothing. The amount of vibration that speakers, even with more modest chassis design, is miniscules. Couple of napkins is enough to decouple them. The amount of sound vibration coming from the woofer is several magnitudes of order more energetic. Test it: put your hand on a speaker cabinet. Does it vibrate? Check the woofer cone, does that vibrate? And what would be the difference between the two? If we use best case scenario, you can estimate that solid-> solid can transfer energy 1000 times better than air-> solid. Are we even close if we did magnify our vibrations and assume all of it is transferred without losses... Yup, nowhere near the same caliber.. The amount of air that is hitting EVERY INCH of the room are way, way more than vibrations that could come even poorly decoupled speakers.. 5mm, 10mm mats or rubberpads are all that are needed.
People get crazy about acoustic isolation, but for the people who were just going to put their monitors sitting on their ikea cardboard desk, mats are probably a good idea! I really like what genelec and audyssey do with their built-in mounts to get some clearance above the surface and angle them up a bit - just take them off if you have proper stands.
That's complete lie. I've had enough problems in my and my friends studios with non isolated studio speakers starting to vibrate the table or any structure they're on. Even heaviest tables often have some weird and wonderful resonant modes and those drive you crazy when you're not hearing what comes out of the speaker but your table resonating. Isolation is a very good thing indeed to minimize that. And yeah, my current studio table has a mass of ~90kg, it's very rigid and even that resonates on certain frequencies if I don't use the thick rubber isolation stands that come with my Genelec 8020A's. And I don't even have to floor them all the way. The whole table doesn't but the table surface does. Though heavy and rigid, it has some weird harmonic mode at around 80hz. Vibrations in the air don't have enough energy (or the energy doesn't couple as easily) to make it resonate audibly though. And those speakers are as rigid as they come and weigh a ton considering their size. and they still can be felt vibrating when bass hits even on modest volumes... until you use the isolation rubber pads and those vibrations vanish.
I have a pair of Boston Acoustics HD5 speakers connected to a Yuanjing T-amp with its own linear power supply. They lack a little in the low end but the sealed construction and the special HD soft-dome tweeter give them exceptional transparency. I've had them on my shelf for five years now and they still continue to surprise me at times.
Hello, could you do a teardown of Finnish Genelec studio speakers? They are cast alloy and more interesting insides. perhaps some reader can loan you a pair OSLT
I've a pair of Focal bookshelf speakers that will operate for about 90 minutes and then go silent. The power indicator still lights up as normal, but sound just goes away totally. What could be the problem?
Hi, very detailed review. Last year i had the oportunity of testing a pair of ADAM A7X, I must confess I'm in love with them...Do you know them???? Best regards from Argentina
Maybe a stupid question, but you do mention it a lot. Earthing the bolt that goes through the torridal transformer creates a shorter secondary turn, which I understand. But I'm assuming people put it there for safety, IE, transformer shorts you want to pop the fuses. If they don't earth the bolt, is it earthed via the case instead, that's connected to the transformer?
The solution is simple: just make sure the bolt doesn't have a path to ground on the top side. There will still be potential across the bolt of course, but at least it is floating under normal operation. Or use a plastic bolt :)
Any idea why my cms 65 version has suddenly blown? (sounds all distorted) It's never been played loud :'( And Focal have discontinued it. Pleaase Helpppp
What! No switching power supply with a class "n" or "t"? Amp on a chip? How old are these? Seems like they could have doubled the power with less heat and loss while keeping quality good.
Yes but smp's are noisy and harder to filter then a linear psu. That an in audio equipment they use linear psu cause it dose not make qlot of high frequency noise on it's outputs and it takes less parts to build a desint linear psu then a desint smp. Fewer parts to fail and easear to filter the outputs
@@EEVblog XLR is THE standard in professional audio. The only time I used TRS was for music instruments, guitar amps and headphones. TRS isn't that great because contacts are completely exposed on the male plug and it does nasty things when inserting (contacts get shorted during insert).
@@EEVblog, Sorry for a small book... I'll try to be as terse as possible. I don't meant to put you in place or anything, I just want to tell you why I like XLR... maybe you'll find some of it interesting as well :) TRS hasn't caught on in professional use mainly because it's mechanically not robust enough for the road and isn't directional in it's mechanical or electrical design. It doesn't have a locking mechanism by default and is a bit of an arse to solder compared to XLR when you ultimately need to fix that broken cable when on a tour. I've done that plenty of times. Directionality in mechanical design makes sure there's no risk of wiring inputs to inputs or outputs to outputs. With XLR you can't do that unless you use some weird sex change adapters or build yourself a non standard cable, both which are nothing a professional would use or even need to use with proper gear. It also makes sure the correct grounding scheme is done since the shield ground and signal ground are separate in a sense that the shield ground is only connected to chassis ground at the output end of the XLR-connection between devices. Thus any interference picked up by the shield is taken to the signal source, through the device chassis to earth ground and doesn't cause problems to the signal ground potential since they're kept separate (well... star grounding scheme at the power input connector). And obviously, using XLR, ground is always connected first, and separated last when plugging it in/out, on TRS, you plug it live with your own peril... especially if you're running phantom power since during connection there's a moment where ground is disconnected and hot/cold are shorted to ground etc. :D There's also an advantage in RF-immunity since the cable shield connects to the XLR connector metal case that almost completely wraps around the whole connection interface, thus making sure there's as good of a coverage as economically viable all the way through the cable run and through the connector hole in metal case. There are also XLR-connector designs that have feed through EMI-filter designs for absolute RF-immunity. (see www.neutrik.com/en/neutrik/products/xlr-connectors/xlr-cable-connectors/emc-series ) Anyway... that's my small list of reasons to use XLR in professional environment. Though I do agree, that for most people it's a bit of an overkill, but: "I've never regretted using XLR instead of TRS" :D
@ppdan TRS isn't for guitar amps or music instruments (if you refer to guitars/basses). TRS is balanced, and all these musical instruments uses TS 1/4" plug unbalanced connections. Only some synths or other generators and/or processors use TRS I/O. Anyway, these speakers have RCA connections, I don't see why they can't have also a TRS connector parallel to the XLR one.
12:00 Looks similar to what's inside the Anker soundcore. Look up Anker soundcore teardown..it has a horn shaped thing in the middle which anker claims is for "increasing bass"
There are two ways to get extended bass in a speaker, larger box or a port(s). Ported enclosures (aka bass reflex) add an acoustic resonance somewhat below the natural resonance of woofer+box, which extends the frequency response down in frequency (or, if you get it wrong, produces a boomy resonance at a single frequency). Alas there is no real substitute for a large speaker enclosure, although adding a port can increase power handling by loading the woofer's resonance down.
whats the actual difference between, say, a Panasonic cap and one of those Yihcon ones? surely it cant be that hard to make an electrolytic cap. is the distaste for off-brand caps based on actual recent test results and/or failure rate stats, or is it just a hang-over from years ago, the early days of Chinese electronics, the capacitor plague etc? is there any reason why some Chinese company cant make perfectly good electrolytics at half the price of Panasonic?
that's certainly possible! the problem is that manufacturers are always changing/improving their products, so by the time you have enough historical data to really gauge the reliability of a component, it's probably already obsoleted. companies like nichicon and panasonic have built a reputation for making quality capacitors, so that's why they are preferred over lesser known brands.
Yes of course they can make good caps, but the issue is they haven't built up a reputation of design and manufacturing reliability over many decades like the other manufacturers have.
Fantastic but the op amp and electrolytic sud not be that quality. esp op am, there TI 16x4 that is only slightly more expensive compared to the 50 cents 70s op amps
While I know it's convenient I just don't want my amplifier combined with my speaker/cabinet. I want to be able to mix and match the electronics and the electromechanical portions.
It's not just convenience, it allows the crossover electronics to come before the power amps and gain much lower distortion in the process. Yes there are some active speakers with external crossovers but most people are put off having to buy at least twice the number of amps to power the thing.
@@robbedoeslegrand236 Yeah no, you just need to do proper testing (Which is hard in mass production i guess?) Remember, Japanese capacitors were once also ranked as one of the worst... (It's just upto QC)
Now, it's either a split case or you at least know how to open it quickly. Get a couple standalone amps, hook them up in place of the internal ones and listen for the hiss. It would be very interesting if the hiss remained
Audiophiles are basically a variation of new age woo practitioners. But if you're into that sort of thing I can sell you some directional speaker cables and Rhodium connectors for around 10k
@@HashanGayasri would you like to buy my granit plate wit natural rubber feet specialy design to avoid vibration? Our granit is cut in the heart of the hardest granitic stones from bretagne in france, then analyzed in hour laboraties to ensure perfect crystals alignement! The rubber feet are made inthe purest fair trade natural rubber and conic shaped. This to not comunicate your house vibration to your speakers! ONLY 15k each only for the first 10 buyers!
i didn't see any wrong with MIC. I am not sure if you could buy anything better than made in china at the same price. not for this topic, just a grneal thought.
If something is being done to save cost you can rest assured that the very highest levels in the company would be well aware and be singing praises, like every other business they exist to make as much money as possible. It’s fairly well made, but still we are talking probably $25US for that Chinese build... so they are still very cheap... and a $4 difference in capacitors would be noticed on the BOM as a roughly 15% increase in total cost...
someone outthere I don’t know that I would call it religion as it is a product of a great many “off-brand” electrolytic capacitors, particularly out of mainland Asia, having a very poor reliability and performance record over a number of decades. A large percentage of the electronics discarded each year are discarded as a result of these cheap electrolytic capacitors having failed prematurely (some after less than a year of service) - in fact the majority of flat panel failures can be attributed to to just two causes: electrolytic filter capacitor failure and failure of the flat flex panel to board connections. That is true of a great many other modern electronics we throw out each year as well. Compare that against the typical 20, 30, even 40 year service life from the better quality electrolytic capacitors brands and you have a very practical reason for the concern when cheap off-brand capacitors are found in what is supposed to be premium gear.
4:22 First quote is actually from Mary Poppins when she pulls out the ficus plant from the bag ;-D ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-AivZSC9J3Rs.html
These are still just blatant copies of Genelec 8000-series monitors... check out Genelec 8020A (released 2005, 6 years before Focal equivalent.) Genelec doesn't skimp on build quality :)
Imagine all the design, technology and thinking that was just given to the Chinese for free just to save a few bucks whilst the Focal CEO whistled all the way to the bank and/or his mistresses boudoir!
Acoustic design equations have been open to the public for many many decades, I’m sure even Chinese high schoolers could design something comparable from scratch, speaker design isn’t all that complex since the Ph.Ds of the 1940s figured it all out...