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Troels Gravesen SBA-761 Project Build


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I have SB Acoustic drivers (SB17MFC35-4 , SB29RDNC-C000-4) in my car and they sound fantastic , this was my first time with SB Acoustics and i was very impressed.

 

The SB17MFC have amazing tight clean bass and can be cranked very hard , (150w rms amps) with no change in sound , blows me away every time i really crank it.

 

So i wanted to use them for home and began looking for diy speakers using SB acoustics drivers.

 

When i found the SBA-761 on Troels site (http://www.troelsgravesen.dk/SBA-761.htm) , it matched what i was looking for and had the crossover values so decided to build them.

 

I have done most of one cabinet and will begin the next one shortly.

 

He uses 20mm Birch Ply , i have used 25mm MDF and have made the cabinet deeper to compensate for the differences.

 

The baffle for the MW16 and MW19 is 20mm (16mm + 4mm MDF) so as to keep the correct tweeter offset.

 

I also knocked up a quick PCB for the crossover (i'm an electronics tech and it's part of my job designing PCB's), after building it i wanted some way of testing it so i used DATS V2 impedance sweep.

 

Interesting thing i found when comparing the 2 crossovers was i had a small difference in the dc resistance from one to the other.

 

After some more investigating and resoldering one of the coil wires it was due to a small amount of enamel coating still left which didn't allow the solder to fully flow around the wire.

 

Visually it looked good , so i am glad i tested them as now they measure identically. 

 

I have everything except the 2 x MW19P-8 drivers , i will be purchasing them in the next month or so through WES Components , i have an account through work.

 

I couldn't make up my mind as how to finish them but i have ended up buying some of this https://crockerspaint.com/eshop/Natural-Stone-and-Tile-Self-Adhesive-Lining-Papers.html

 

I liked the marble black , something different , i guess we'll see in a month or so.

 

If it doesn't turn out ok i can peel it back off and go a different way.

 

I am a bit annoyed at myself though as the tweeter face cut out is 1.5 mm to big , i have a Jasper router jig and because of where the router bolts to it the pin hole i needed was hidden so i was lowering it down onto the pin and was 1 hole out , doh , normally i do it the other way , insert the pin into the jig first.

 

Now i am trying to figure out how to make up the gap , i do have a 3d printer and could print a ring that would fit perfectly.

 

I will update as i progress through the build.

 

Cheers

 

David

 

Crossovers:

Solen Inductors 14awg

Dayton Audio Caps ( i can't justify the expensive caps)

Low inductance resistors.

No ground plane on the PCB.

 

 

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Marble Black DC 200 2713 (Small).jpg

Edited by DavidH71
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One down ,One to go.   I'm pretty happy with how it turned out , look like high end speakers.   Of course i couldn't help myself and i'm listening to it now and although only one a

I have SB Acoustic drivers (SB17MFC35-4 , SB29RDNC-C000-4) in my car and they sound fantastic , this was my first time with SB Acoustics and i was very impressed.   The SB17MFC have amazing

I will get some finished photos.   The subwoofer is one i stumbled across on the net about 20 years ago , Pro PA driver JBL2226 , sand filled walls , weighs about 160KG , some build photo's

Argh , i have to make the front baffle's again as i miscalculated , there is supposed to be 115mm from the top of the cabinet to the baffle that has the MW16 and MW19 mounted to it , i currently have 120mm.

 

Oh well at least i discovered this before i glued it on to the cabinet and only have to remake the front baffle's , i just picked up some 4mm ply and have plenty of 16mm MDf to make up the 20mm thickness.

 

The first cabinet now has the crossover mounted , wiring routed and the 8mm felt glued to the panels , next step was to glue on the baffle.

 

I have started the second cabinet.

 

I now have the MW19 drivers , obviously it will be a bit longer before i have them finished , i hope to get a lot done over easter.

 

David

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I have managed to fix the tweeter face cut out being to big by carefully routing a 1.5mm ring from 6mm MDF .

 

I made the ring slightly larger than i needed then cut little pieces out of it until it fit perfectly in the circle cut out then glued it in place.

 

I ended up with about 1mm left protruding upwards and just sanded it flush.

 

Tweeter is nice and snug now with no gap , i'm happy.

 

Cheers

 

David

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One down ,One to go.

 

I'm pretty happy with how it turned out , look like high end speakers.

 

Of course i couldn't help myself and i'm listening to it now and although only one and not loosened up yet ,it sounds pretty damn impressive , very solid in the bottom end and vocals sound like there in the room with you , very clear.

 

Can't wait to get the other one finished and get the full stereo sound.

 

I'll give another report once i have both speakers done.

 

Cheers

 

David

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Nice work- bet you can't wait to get the second one done now! Don't rush it- any complacency or rushing to do #2 might see a few mistakes done. That's probably what I would do, anyway...

Let us know how they sound please.

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Thanks mikk,

 

It actually looks better in person , the photos don't do it justice.

 

I thought i better mention the sticky back plastic i used was very easy to apply. I used their recommended tool( a piece of hard plastic with felt on on one edge).

I only had 1 bubble and that was very easily rectified (lifted back up and re-apply) , probably took me about 30 minutes to cover the one speaker.

I wasn't sure what i was in for as had never used it before but it was ridiculously easy to apply.

 

I'm about halfway through the other cabinet , i won't be rushing , the glueing process slows things down quite a bit , i like to allow at least 6 hours (preferably 24hrs) before i unclamp and move on , in saying that i might have it finished this weekend or early next week.

 

Oh and one other thing i only discovered after mounting the drivers was that i need to blacken the MDF behind the drivers as on certain angles you can just see the yellowish MDF , which on a dark cabinet stands out.

 

Cheers

 

David

 

 

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Now i have spent a bit more time with the one speaker i am very disappointed.

 

My previous comments were only after about 15 minutes of first playing music through them and i think i was a bit biased as i just built them .

 

The strong bass is actually one note bass (70hz , confirmed with REW measurements).

 

I have since blocked the bottom cabinet port and it has improved it a little bit , but still far from what i was expecting.

 

The sound just doesn't excite me and i find it very hollow , the vocals just don't have any meat to them , kinda echoe.

 

No sparkle , but i can bring the tweeter level up a bit by changing a resistor in the crossover and that should help a little.

 

It's weird the longer i listen the less i want to.

 

I know i'm judging by just one speaker and i hope things improve a lot when i have 2 running.

 

Not what i was expecting at all especially after reading numerous positive reviews of the Satori drivers and my own experience with SB drivers

 

My car setup sounds way better although that's an active setup.

 

Also i think they are a bit tall , i have had to angle them down a bit for my seating position.

 

I am still hoping they need to loosen up more (have been playing music every night since i set it up and also about 4 hours of 10 - 15hz near xmax)

 

I have gone over all my calculations for box volumes and i'm about 0.3 litre bigger than his spec and the bottom port is not as wide which means it is tuned about 1hz less , and my cabinet is 15mm longer at the bottom ,  i don't believe this is it.

 

I have used different crossover components , the 1.2mH and the 0.33mH inductors have slightly less DCR than his and i have the dayton caps not his expensive AlumenZ caps

 

The REW measurement doesn't show anything bad (except the 70hz hump) , from 500hz up it is a very smooth line ,  very closely matching his frequency response graph , below 500hz my room modes takes over and it's a bit lumpy.

 

My Dats impedance sweep matches his as well.

 

I have excactly the same cabinet damping as his but i will experiment with removing some.

 

So i am a bit lost on where to go from here to fix/improve it. 

 

At this point i'm a bit bummed and in no hurry to finish the other one (i will).

 

David

 

 

Edited by DavidH71
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Excellent post - I feel your pain!

 

Too tired and hungry to go into detail, but suffice to say, I've been in this position many times (constantly?) in the 8 years or so that I've been posting here on my speaker builds.

 

In short, EVERYTHING has to be right before you get your satisfaction.

 

You DO need the other speaker going, before judging any further. Stereo is stereo. One time I posted about my "improvements" to a centre speaker crossover. A question came in "how does it sound?". I could find nothing to say, as the problem exists: how do you evaluate a centre speaker?. There's no commonly available mono music, it needs to be heard in context, blah blah, so I'm still in the dark there. So your expectation of one channel bliss is even more unlikely.

 

The bass/treble balance etc is highly dependent on room, and listening position, so REW is not probably not relevant at the moment.

 

Some aspects of your build are very stimulating. I hope you can get the other speaker up and running (don't burn the 1st one in too fast!), and all should fall into place soon.

 

 

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Thanks BioBrian

 

Last night i changed the tweeter resistor to bring the level up a bit and that has had quite a dramatic improvement.

 

Also i think it is slowly improving or i'm getting more used to the sound.

 

Your right about stereo , i came to the same conclusion last night after thinking about it more , i need both going before judging them.

 

Up until last night i was just listening to it alone , i turned the subs on and actually the balance is very good.

 

When i first built the ultimate subwoofer 15 years ago i was a bit disappointed but soon realised it was because i had only heard distorted bass before then and it took a little while to fully appreciate its performance , i think a bit of that is going on here too.

 

So before i give any more info on sound quality i'll wait until it's all been together for a week or so.

 

Anyway , i'm much happier now.

 

Cheers

 

David

 

 

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Good to hear!

 

I can't know your experience, but I always find that new drivers and crossovers sound terrible for a few days, so what you described comes as no surprise.

 

Also, and it sounds like you're pretty switched on in the electrical department, but you wouldn't be the first to inadvertently get one of the driver polarities the wrong way around. Eg, it's so easy to change red and black wires at the crossover, and do it again at (in this case) the tweeter. That makes them sound weird.

 

I was surprised to see there are only 2 caps in the crossover - must be Troels' cheapest ever! You've left yourself a neat upgrade path (if there's room on your PCB) if you ever think the $4.29    8.2uF could be improved upon...   Just had a brief look: $800 for copper foil, $150 for Alumen, $70 for Superior-Z, and any number of other choices. One must stick to one's principles though, so don't let me put any devilish thoughts in your head. I haven't tried the copper foil, but the Alumens are as close as I've come to "no cap". I'd replace both yours with Sup-Z, myself. After all, the biggest cost in a quality build is your time and TLC, which is nice to see balanced by good driver (done) and component choices.

 

The cap in the bass section (0.1uF is tiny) looks to be affecting quite high frequencies - I suspect the blip around 5kHz may be due to this biggest driver's breakup area - so it doesn't surprise me that Troels chose a Silver-Z cap there. Could well be important in the sound you are hearing.

 

Looking forward to further progress with your build.

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I am confident the wiring is correct , REW would have shown a dip around the crossover frequency if the tweeter was reversed and i double checked.

 

I struggle to justify the expensive caps for the supposed small improvement  , i'm in the electronics industry and those caps just seem ridiculously expensive to me , thanks for the suggestions anyway.

 

Yes the small cap and resistor is to attenuate the 5-10Khz region of the MW19 as Troels said he didn't like it without it.

 

I had a busy weekend and have finished the second one except i ran out of the covering and only have covered the front and back so i could install the drivers , port and speaker terminals , it was late last night so haven't had a chance to listening to them , but i will when i get home from work today.

 

Cheers

 

 

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Sorry, it looks like I barged into your thread with too much of my own agenda. Can't help getting a bit excited about Troels builds.

 

With the caps thing, one point I was trying to convey is that with this design, it would be relatively cheap to do a definitive test - only 4 caps. To do the same test on some of Troels' later builds would cost many thousands, and you couldn't just do a quick A-B with a couple of switches and 6 wires out the vent hole, like you could some day, if tempted. (I'm sure it wouldn't be just me interested in the results).

 

I agree that the cost of present-day supercaps can look pretty sick, and my take is that it needs to be all in proportion. With the rest of life too - when you consider what certain people spend on underwear, or wine, the caps seem quite cheap for their lifespan, but only if you do appreciate an improvement.

 

Nice that you can add the rest of your covering without having to remove all the drivers etc, as with the sanding-painting drama.

 

I don't mean to be anything but supportive - keep up the good work.

 

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No worries Brian,

 

I know you are only trying to be helpful.

 

All tips/suggestions are welcome.

 

Hopefully i will be able to give my opinion on the sound in a week or too , i'm not going to rush to judgment this time.

 

Thanks 

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I spent a couple of hours last night listening to the them and i couldn't help myself and say something.

 

In one word "WOW".

 

The bass is awesome , you could quite happily go without a subwoofer , it produces every note except the very very bottom registers , i am totally blown away , sat there with a big stupid grin on my face probably for those 2 hours.

 

It is exactly what i wanted as i need strong bass to keep up with my subwoofers , always felt my old speakers struggled in this regard , i haven't tried it with the subs yet as i was enjoying the sound i was hearing too much , but i am confident it will be awesome.

 

I kinda see what Troel's means when he mentioned they sound different , they do but in a good way.

 

The midrange is very strong but not harsh or overpowering  , it puts vocals right in front of you and sound very crisp , clean and smooth.

 

Top end is also very clean and i have the sparkle i wanted with no harshness.

 

But for me the most impressive thing is the bass quantity and quality , i am a bass head.

 

I mostly listen to electronic/Drum & Bass.

 

So i am over the moon with the end result and they will only get better with time.

 

Happy Dave   ???

 

 

 

 

 

 

 

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I spent the weekend setting up my two subwoofers with MSO software ( Multi Subwoofer Optimizer ) and what a difference.

 

I now have clean tight non resonant bass where as before there were definitely quite noticeable resonate peaks which muddied the sound.

 

Dual subs and MSO are definitely worth it. 

 

They blend very well with the SBA-761 speakers crossed at 60HZ

 

Cheers

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  • 1 month later...

Hi

Good job on the speaker build, perhaps you could post some finished pictures, or maybe you have a thread in the my system pages.
 

You mention the subs and the MSO, but don't seem to give details, what subs do you have and what is the software

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I will get some finished photos.

 

The subwoofer is one i stumbled across on the net about 20 years ago , Pro PA driver JBL2226 , sand filled walls , weighs about 160KG , some build photo's attached.

 

I built one back then and have only just recently built another one.

 

Link for my sub.

http://mainkas.tripod.com/page/audio/allmighty/tangen_sub2r.htm

 

MSO is Multi Subwoofer Optimiser , it is for use when you have more than one subwoofer and more than one seating position to optimise for.

 

You take measurements with REW at the different listening positions of each sub then the main speakers.

 

Then import these measurements into MSO and set some parameters.

 

It will try to give the flattest output for the subs taking room modes into account and blend your subs with your main speakers. 

 

The end result for me was i no longer had the strong resonant frequencies in the bass from the room modes , nice even bass.

 

I have been used to the sound with the strong modes so initially it felt like it removed a lot of bass but it is actually more accurate now and all bass frequencies are the same level.

 

MSO link.

https://www.andyc.diy-audio-engineering.org/mso/html/index.html

 

Cheers

 

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  • 5 months later...

Just thought i would put this here in case it's helpful to someone , a download link for a google sketchup i did for the SBA-761 in 25mm MDF and 20mm baffle (16mm + 4mm MDF)

 

Edit: I have also now included in this link my crossover PCB Gerber files if anyone want's to get them made.

 

https://drive.google.com/drive/folders/18pD_XOC1PUSxTBHpDr4CGAZh2SWfwh_O?usp=sharing

 

Enjoy

 

David

Edited by DavidH71
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  • 2 weeks later...

David,  Thanks for the great thread.  I am thinking about building the SBA761 and did not find alot of user experience on the web like your build thread. 

You went from disappointment to delight in this thread.  Was that a result of listening to just one speaker and going to two?  Or was it some other crossover mod you made?

 

Thanks in advance for the help.

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Hi,

 

Yes one thing i learned is don't judge them until both are built

The resistor i changed in the crossover to bring the tweeter level up a bit also improved the top end to me and i preferred this.

I am very happy with how they turned out and enjoy listening to them.

 

Cheers

 

David

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  • 1 month later...

A bit of an update.

 

I just upgraded my AV surround amp from a Sony DN-1080 to a Denon AVC-3700H , one of the main reasons was that I wanted the pre outs to run a dedicated amp for the main front speakers for music.

 

My old system was a Playmaster pro series 3 amp , Playmaster preamp , and quality cd player before I purchased my first surround amp years ago and retired it all.

 

Since building the SBA-761 I have never quite been fully satisfied with the sound , they sound good but something was missing.

 

So now I am running the Playmaster pro series 3 amp from the pre outs on the Denon.

 

" HOLY CRAP " what a difference , in the years I had been using AV amps I hadn't quite realized how much music sound quality I had lost.

 

The difference is huge , the sound has really opened up now , the sound is now what I was expecting from the SBA-761.

 

Now it gives me chills down my spine , it sounds that good , I hadn't felt that for years. 

 

I hear sounds now that I have not heard before on very very well known tracks , and the voicing is on another level , voices of all types sound superb , never have I heard such a forward midrange that just sounds so natural and real with exceptional clarity.

 

It has made that much of a difference that I am thinking about changing the tweeter resistor back to the original that was specified as it's almost too bright now on certain music.

 

As an experiment I have ordered 2 of these Holton HPA-NXL200 R4.5 - Advanced Amplifier Modules to replace the Pro series 3 amp modules and two SMPS300RE power supplies from Connex electronics ( Connex SMPS2000RxE currently powering my sub amp with a stereo IRS2092 amp module ) to see if I can improve it even more as from what I can gather the Holton modules are well regarded and have great sound.

 

So if you value music and are using an AV amp for amplification then forget it , you need a quality dedicated amp.

 

Now I am going down this rabbit hole again I have also ordered two SB acoustics SATORI TW29TXN-B-8 / TeXtreme tweeters to try in my SBA-761 speakers.

 

They supposedly have sound quality very very close to the Beryllium version , can't wait until I get to try all this new stuff out. 

 

I will report back with my results.

 

Cheers 

Edited by DavidH71
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I can remember the setting, but in the menu of the denon you can switch off the main speaker power out and only use the pre-outs - this improves the performance of the pre-outs further.

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I'm still learning to use the Denon but I thought you could only have all the amps on or all off , no in-between , in which case I still need 5 more external amps , could be wrong though , I will check when I get home , thanks.

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  • 2 weeks later...

Wow , I am really surprised and impressed.

 

The Denon has Audyssey XT32 calibration and after performing the calibration and limiting the frequency range to 500hz it has done a much better job than MSO did with my dual subwoofers.

 

With MSO I still had one particular strong resonance which I could never quite get rid off with multiple tuning attempts , which was very annoying on certain tracks that used a lot of that frequency as it was noticeably louder than the rest.  

 

Now after calibrating with the Denon and the included mic , it has removed the resonant frequency and the bass sounds really really good , very even in bass level through all sub frequencies.

 

I have never heard my bass sound this good , awesome.

 

I am still awaiting the Connex SMPS supplies from China , I have the Holton amp modules and I also knocked up my own surface mount version PCB's for Rod Elliotts Project 23 Power Amplifier Clipping Indicator as my Playmaster amps had clipping indicators and I would lose that feature when I fit the the new modules , I should have the clipping indicators built and tested by the end of this week , I have also uploaded the Gerbers and Schematics for the clipping indicator on my google drive if anyone is interested , all resistors are 0402 size except the 2 large ones they are 2512 size.

 

The SB Acoustics Textreme tweeters will be another couple of weeks as they are so new WES didn't have any in stock yet.

 

Cheers.

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  • 3 weeks later...
Posted (edited)

I had to make another version of the clipping indicator PCB's (clipping_ind_V2) , I changed the resistors that will dissipate heat to standard size through hole resistors except for R9 which I made a 5W through hole resistor , R4 and R5 can't be 0402 surface mount size as I discovered because of heat , I have tested it and it works well now.

 

I now have the SMPS from Connex so I have everything to rebuild my amp , should be in the next week or so .

 

I am still awaiting the Textreme tweeters to try.

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I feel like such a dick.

 

When I rebuilt my subwoofer amp from mono to stereo for dual subs I used a Connex IRS2092 class d stereo amp module , you need to wire it so 1 channel is out of phase with the other channel to avoid bus pumping (class d thing).

I had done this but when I was fitting my clipping indicator I discovered I had misread the labelling on the outputs of the amp module and didn't have the inverted channel output swapped around so I actually had one subwoofer out of phase with the other.

I had not picked this up as I also fitted the second sub at the same time as doing the amp mods and the outcome sounded different but I had expected it too because of the second sub.

 

I fixed the amp speaker terminal wiring and holy crap it all made sense now as I was a bit underwhelmed with the addition of the second sub and expected more but now I am finally getting what I expected from my 2 subs , huge difference , I almost have too much bass (is that possible?)

 

My house doesn't like it much , bloody walls/windows rattle like crazy , not sure what I can do about that.

 

The sub I have also had a bit of EQ boosted down low using an active filter setup that I made a PCB for and fitted to the amp years ago but because I upgraded the internals of the amp recently I decided to change that function to a 2 x 4 Minidsp HD which I had laying around.

 

What I hadn't realized by just making the exact same filters in the minidsp as my PCB version was that I also had a low pass on the sub which is not necessary because the AVR should be controlling the crossover frequencies from sub to mains , with it like this I was missing upper bass as the subs low pass and the AVR low pass were adding and giving me double the slope so instead of 24db slope it would have been more like 48db which means the sub wasn't blending correctly with the mains and missing upper bass. 

I removed this low pass filter at the same time as discovering the wiring out of phase on my sub amp so these 2 changes happened at the same time.

 

The result is my bass is on another level and I am currently going back through listening to my old bass heavy favorite tracks again as it just sounds so damn good now.

 

I am so disappointed in myself for having it this way since I built the second sub months ago and because of my mistakes not getting the full potential out of them.

 

I am slowly assembling my stereo amp with the Holton amp modules.

 

Because I have already pulled apart my Playmaster Pro series 3 amp I had to wire the SBA-761 speakers to my Denon X3700 AVR

and could tell instantly the drop in sound quality , AVR amps are no good for quality music amplification as I have now clearly proven to myself.

 

Still waiting on the Textreme tweets.

 

Cheers

 

David

Edited by DavidH71
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Don't knock yourself out over a dumb mistake.

If I started a thread titled "I'm a DIYer and I've never stuffed up" it would be a very, very short thread ?

Who hasn't blown up their share of semiconductors?  Or wired output transformers out of phase?  Guilty on both counts here!

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@DavidH71 It’s not even just DIY. When I was working at a hifi shop 15 years ago, we had a visit from the head engineer of an Italian manufacturer to demonstrate some of their new high-end kit. He set it up himself and spent the better part of an hour trying to tune it in, getting increasingly irate, swearing in Italian and blaming the terrible room and filthy power and whatever else came to mind, for the lacklustre sound. 

 

Turns out, he had one speaker wired out of phase the whole time ¯\_(ツ)_/¯ 

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I spent yesterday listening to the Holton amp modules.

 

I think I am going to fit the Playmaster pro series 3 modules back as they sounded better to me.

 

I'll give it another week before I decide for sure.

 

The things I liked when I first set up the Playmaster were gone with the Holton modules , the clarity wasn't there compared to the Playmaster , there was no sparkle or excitement to the sound , very boring , maybe good for really bright speakers , oh well only way to find out was to try.

 

Still waiting for the Textreme Tweeters.

 

Cheers

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Posted (edited)

Well I have fitted the Playmaster Pro series 3 modules back with the Connex SMPS power supplies and it works very well , no noise and very quiet and weighs quite a bit less.

 

While I was at it I also changed the amp modules input transistors Q3 Q4 (BC556) to KSA992 (different pin out so you need to bend the legs to match) and matched their Beta and Vf , I also cable tied them together with some thermal paste so their thermal properties stay the same.

 

I am now back to the sound I am very happy with , the Holton modules never did it for me and were just very boring to listen too.

 

I think I will be keeping the Playmaster Pro series 3 amp for a while , I really like it.

 

I guess audio is a personal thing with personal preferences as everyone doesn't hear the same. 

 

I queried my tweeters with WES and was just told there are production issues with them and they have been delayed until the end of April , bummer.

 

Cheers

Edited by DavidH71
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I'm waiting on a tweeter surround ring for mine (cracked the surround ring screwing it down on install) from WES, is taking ages..

Are your tweeters SBA?

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Yes , SB Acoustics TW29TXN-B-8 Textreme tweeters are what I am waiting for from WES components.

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Ok, sounds like i'm in for a bit of a wait too.  I ordered 20th January and was told around 6 weeks.

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  • 2 weeks later...

I also wanted to try some SOT-23 surface mount PNP transistors in my Playmaster amp (Q3,Q4) , as the Playmaster PCB is configured for TO-92 through hole , I needed some adapters so I knocked up a PCB , the gerber files for the PCB are on my google drive. 

 

Out of curiosity I am also building the Silicon Chip SC200 low distortion amp modules and will give them a try too.

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Oh and one other thing i only discovered after mounting the drivers was that i need to blacken the MDF behind the drivers as on certain angles you can just see the yellowish MDF , which on a dark cabinet stands out.

 

Cheers

 

David

 

 

Snap, happened to me as well on a pair of speakers I made a few years back. Not terribly noticeable but I knew about it, a source of irritation every-time I had the grills off.

Edited by kiwilistener
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  • 3 weeks later...

Yeah , finally my Sb Acoustic Textreme tweeters will be delivered today from Wes , hopefully I will get a chance to fit them this weekend also I should have the SC200 amp ready to test as well , I will report back in a week or two on the outcome.

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I fitted the Textreme tweeters on the weekend , I also changed the tweeter level resistor from the 4.7 ohm I previously fitted to a 6.9 ohm as the sensitivity of the new tweeter was higher.

 

Wow , these are impressive tweeters , the airiness has improved a lot as well as percussive higher frequencies and also the stereo imaging has also gone up another level which I didn't expect.

 

I think my main problem with the original tweeter response I was getting was that I came from listening to the Vifa D25AG metal dome tweeter for the last 20 years and was very much used to the metal dome tweeter sound so when I built these I was a bit underwhelmed by the tweeters and was after more edginess.

 

The Textreme tweeters seem to give me that sound but without harshness which the D25AG could suffer from on certain material.

 

Overall I am very very happy with the outcome and can highly recommend these tweeters.

 

I am still slowly assembling the SC200 amp to test as well , hopefully sooner than later.

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