0x0023 - SB-S407 Speaker ReCap
ฝัง
- เผยแพร่เมื่อ 12 มี.ค. 2018
- My speakers have been sounding a bit distorted, time for a recap!
Since the concept here was very simple I thought I would make it a bit more interesting by taking a look at how the distortion is effecting the signal on a scope.
I was caught off guard by the shift the signal did on the mid. But the capacitors were fully dead so weird results make sense.
It's hard to convey the sound of speakers over a video and that is only compounded by it being re-encoded for streaming. The initial problem isn't even that noticeable in the beginning. So you can just take my word that it sounds better. - วิทยาศาสตร์และเทคโนโลยี
did the old capacitor short out on a certain frequency range or something?
Yeah, I forgot to explain how this works in the video. The point of the crossover(the PCB) is to create a cutoff frequency range for each driver(speaker). This is done with inductors and capacitors ( www.apicsllc.com/apics/Misc/filter2.html ). When the capacitor failed the capacitors failed the speakers were left with just the inductance causing a phase shift (See "Sinusoidal Waveforms for AC Inductance" www.electronics-tutorials.ws/accircuits/ac-inductance.html ).
You son of a biiiiiiiiii...
hahahaha
Oh my god... I just randomly click this video... and more or less see MY Speakers!! I have Technics SBL 71s from 1983... look identical.. excellent speakers, have had them for about 12 years
Every "Order" of crossover (6db, 12db, 24 db, etc etc) will experience a 90 degree phase shift. It's a well known, documented phenomenon within the audiophile community. (One that actually makes sense, unlike paying $2000 for speaker wire, that is)
my ears are dead
This video drove my cat crazy
My cat freaked out while you swept the higher frequencies. =) Good fun!
The inversion was just the cap doing a crowd wave!
you should probably re-cap both speakers at once so they stay matched!
Nice choice in music selection. Love They Might Be Giants.
Apollo 18 might just be the best TMBG album, it's tied with Flood.
I'd put John Henry in front of Flood and Apollo 18.
They've made so much great music. I couldn't think of one album as the best because I will look at another one and see a whole bunch of iconic songs on there. Even the kids albums are just good music.
@@beanboy89 sacrilege. John Henry was protested against by fans!
Awesome video
Nice vid!
Are your smartphone capable of outputing all the frequecies in the audible range (or the one in the app you use). I heard that many phones cant do that, never tested myself in mine.
Just stumbled on this.. very interesting !! So, did you split the phone output to scope and speaker in parallel ?? and then you said the other probe to crossover. I'd like to re-create this on my workbench to test an old set of B&W crossovers. Really cool ! thanks in advance.
Wish my goodwill sold audio stuff, I could use some
I just picked these up at goodwill for 20$ each exactly why I'm looking into them
Ha! Just like my turntable and phone cartridge setup! Audio Technic AT120LP USB and Shure M97xe. I'm thinking of getting Pioneer PLX1000 turntable though. The Audio Technica is a decent turntable but it has some "quirks" than I am not fond of.
William Jones
Obviously make sure ya hold onto the Shure M97xE cart, as I’m sure you’re aware they’re not made anymore. I use either a Stanton 681EEE w/ VividLine stylus or a Goldring 1042 on my main rig, but I love the mellow sound of a Shure M97xE or M91ED cart in my “vintage rig”.
@@NickP333 Thanks. I did not know that.
Where did you buy the replacement capacitors and what specs are needed for the replacements. Posting a link to the source for the exact replacements would save me lots of trouble/research. Thanks in advance.
Cool stuff. Could you do a video on what tools and knowledge someone would need to re-cap an amplifier or other old electronics? Thanks!
Yanni mouzakis Well... You would need basic eletronic and soldering knowledge.
Basically if you will recap every cap in a old eletronic is not that hard, even without knowing if they are ok or not, just buy a bunch of good caps in the same specs as the ones you will replace. Desolder the old ones off the old board (some have a better solder so a heatgun or more powerfull soldering iron would be neat, and some just a regular 30-40w soldering iron would do the trick). Watch for the capacitor polarity as it doesnt work in the wrong way. So it needs new caps, soldering iron or heat gun.
If you wanna recap only the bad ones it needs a bit more knowledge and tools. You would need to dessolder the old ones and use some kind of tool to measure its capacitance (there are tools for that, and some multimeter do that, and there is a way to measure with standard multimeters/voltimeters), then buy some caps with the same specs as the old ones and replace.
Basically or you replace all of them, or you will have to remove all of them and test them, put back the good ones and replace the bad ones.I wouldnt reccomend to test the capacitors in the board itself, as the measurement may be wrong if they are on their circuit (from what i read about, and saw in some repairing videos).
Thanks for the reply! I don't know much about electronic repair, but I'm curious to learn more. Do you have any recommendations for videos or other resources I can learn from?
3:05 -- This signal brought to you by Whataburger...
@0:05 immediately jealous... I love TMBG, especially that album. Should try and hunt TMBG down on Vinyl.
I have a old stereo technics speakers too with small crossovers and polarized caps. I wondering if I change the caps for non polarized it will work better.
my speaker sound a little bit of distortion. Is because the capacitor or my speaker is semi-blown
I have a pair of these speakers. One sounds fine but the other I can barely hear at all. How can I test the caps to make sure they are the culprits and if so, which ones should I buy? Also, what is the copper coil and could it be bad? I’ve tested all three speakers and they read close to the 8 ohm spec. Any help is appreciated.
Thanks for this informative video. I took a chance and recapped both of my speakers and now they perform like they were intended!
Filters cause a frequency-depend phase shift. I'm not sure why that would be new to you.
Would you recommend this product ( Technics SB-407) ?
What model is that Technics amplifier?
It is an SA-GX303
Hey just bought a pair for $20 what are the specs for the new caps?
Because it needs a reference signal or synce!!
I have the same exact speakers and I know nothing about them. Could anyone tell me what I’m supposed to get to power these things?
If you haven't gotten an answer in 5 months, you could use basically any stereo amplifier to power them. Old (or new) AV receivers work, too.
Is anyone else seeing odd flickering artifacts in his hand at 8:40 or is my graphics card dying ...?
R.I.P. graphics card.
PenorPie actually I viewed the video on my phone and also noticed it so it was definitely not my graphics card (It's only visible on the 1080p60 stream)
I don’t see it.
Eric Smith He said in a recent video that he was experiencing it too and his camera might be dying
I have no clue what you are doing you dont explain how to hook it up or what the waves should or shouldnt be doing of I am a total amateur
All that work for vintage mid-fi speakers.... they were never resolving and transparent new.... kind of thump and sizzle really. That mass-fi rolled off and spitty treble that "beams". about 11khz. But hey, if you dig that sound...
Incidentally, electrolytic caps induce their own distortion and degrade in as little as 3-5 years. Would have been a better idea to use 5% metallized poly caps which measure the same over decades and have no electrolyte to dry up. That, and they are vastly more accurate and neutral than those cheap beer cans.,
Bro your voice coil might be twisted or bent