I am going to log my project here and hopefully garner some advice and knowledge along the way!
Having been on here for a couple years and asked many questions about various possible projects...i have taken the plunge and built some speakers. I suppose like many of us new to this, we don't go about things methodically. So I acquired various drivers along the way that were good value. The Peerless DA25BG08-06 caught my eye as being a very good price from CPC here in the UK. I believe they were about £15 each. The high power handling and low Fs appealed to me as a beginner thinking they would be fairly safe given a possible sub optimal filter. They look nice and 'hi end' and obviously share similarities with some of the Seas and Scan Speak tweeters.
The SB17NBAC35-4 were a bit of an impulse bid on ebay. A guy was selling them via auction and I won them for £65 for the pair. A good price again I thought.
So onto the Leaks. Well these 150s have been in the family for over 40 years. My father bought them new in the 70s and he tells me he bought a Rotel amp and MacDonald turntable at the same time. They are in very good cosmetic condition. The grilles weren't to my liking and so I have recovered them. I gave them a go as Leak intended and it soon became apparent they had issues. The cone tweeters were falling apart and so I purchased some cheap Monacor HT22 to try. It then turned out thay the noise that one speaker was making wasnt from the tweeters after all and one of the woofers was making a clacking noise at higher levels. Maybe I was just over driving them!
Anyway....i decided to really go to work on the enclosures and use the drivers I had acquired...the Peerless and SB. The Leaks are about 15litre and modelled well in winisd. I decided I wanted 'clean fast bass so I didn't port them. I cut the orignial baffle out of the box, added some 'rails' that allowed me to glue and screw a new plywood baffle inplace. I added some bracing and bitumen sheets.
Onto the XO....well earlier in the year my brother bought for me for my birthday a pair of nice old Castle Acoustics crossovers with film caps and air core inductors.....£15 new off ebay. I figured the individual components and the bi wire speaker posts were worth having to build my own XO....obviously having no idea if the values were anything like what I may need!
So here we have a completely random speaker build with a far from sub optimal XO.....what do they sound like...
Amazing! These are the nicest speakers I have had in my system. I love the bass, the treble is well balanced and doesn't seem to have any vices. The only thing I think needs looking at is the upper mid. They tend to get a little bright at higher levels on lesser quality recordings.
I am going to try to draw out the schematic of the XO it is running. I figured that both of the drivers I chose have fairly benign fr curves....admittedly on the manufactures IEC baffles....that the XO I am using will atleast 'work' safety enougj without damaging anything. They sound very clean so I am happy I am not pushing anything too much out of their comfort zone.
Being impetuous I haven't recessed anything yet and I realise the aluminium angle edge is bad for diffraction, but I am happy to forego that to retain the original looks. I have made a sub baffle from foam core and a covered that in wool felt to mitigate that issue. Maybe I wasted my time with that but they look a bit better for it when you remove the grilles!
My next step is to measure them and I am employing the help of chris661 from on here to do that. From there we can tune the XOs to something more suitable. It will be interesting to see how they measure now !
I shall post those results when I have them
Thanks for reading
Having been on here for a couple years and asked many questions about various possible projects...i have taken the plunge and built some speakers. I suppose like many of us new to this, we don't go about things methodically. So I acquired various drivers along the way that were good value. The Peerless DA25BG08-06 caught my eye as being a very good price from CPC here in the UK. I believe they were about £15 each. The high power handling and low Fs appealed to me as a beginner thinking they would be fairly safe given a possible sub optimal filter. They look nice and 'hi end' and obviously share similarities with some of the Seas and Scan Speak tweeters.
The SB17NBAC35-4 were a bit of an impulse bid on ebay. A guy was selling them via auction and I won them for £65 for the pair. A good price again I thought.
So onto the Leaks. Well these 150s have been in the family for over 40 years. My father bought them new in the 70s and he tells me he bought a Rotel amp and MacDonald turntable at the same time. They are in very good cosmetic condition. The grilles weren't to my liking and so I have recovered them. I gave them a go as Leak intended and it soon became apparent they had issues. The cone tweeters were falling apart and so I purchased some cheap Monacor HT22 to try. It then turned out thay the noise that one speaker was making wasnt from the tweeters after all and one of the woofers was making a clacking noise at higher levels. Maybe I was just over driving them!
Anyway....i decided to really go to work on the enclosures and use the drivers I had acquired...the Peerless and SB. The Leaks are about 15litre and modelled well in winisd. I decided I wanted 'clean fast bass so I didn't port them. I cut the orignial baffle out of the box, added some 'rails' that allowed me to glue and screw a new plywood baffle inplace. I added some bracing and bitumen sheets.
Onto the XO....well earlier in the year my brother bought for me for my birthday a pair of nice old Castle Acoustics crossovers with film caps and air core inductors.....£15 new off ebay. I figured the individual components and the bi wire speaker posts were worth having to build my own XO....obviously having no idea if the values were anything like what I may need!
So here we have a completely random speaker build with a far from sub optimal XO.....what do they sound like...
Amazing! These are the nicest speakers I have had in my system. I love the bass, the treble is well balanced and doesn't seem to have any vices. The only thing I think needs looking at is the upper mid. They tend to get a little bright at higher levels on lesser quality recordings.
I am going to try to draw out the schematic of the XO it is running. I figured that both of the drivers I chose have fairly benign fr curves....admittedly on the manufactures IEC baffles....that the XO I am using will atleast 'work' safety enougj without damaging anything. They sound very clean so I am happy I am not pushing anything too much out of their comfort zone.
Being impetuous I haven't recessed anything yet and I realise the aluminium angle edge is bad for diffraction, but I am happy to forego that to retain the original looks. I have made a sub baffle from foam core and a covered that in wool felt to mitigate that issue. Maybe I wasted my time with that but they look a bit better for it when you remove the grilles!
My next step is to measure them and I am employing the help of chris661 from on here to do that. From there we can tune the XOs to something more suitable. It will be interesting to see how they measure now !
I shall post those results when I have them
Thanks for reading
Attachments
Some pics in the correct orientation hopefully...and listening to my Ian Canada/Salas streamer...DCG3 pre and 3255 power amp
Attachments
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Its a nice project and it is good you have re used the original Leak cabinets for their unique styling.
I am sure the Sb will sound good in a sealed enclosure and if near the wall you will get useful room gain anyway. The tweeter has ferrofluid cooling and can work down to 2Khz or so, this robustness and the fact that the castle crossover was designed (I am guessing) for a 2.5-3.0 Khz crossover means it will be safe.
The harshness or excess you hear could be removed by the correct attenuation and crossover frequency for the tweeter or it could be an artefact of the bass mid metal cone resonance in the high Khz range. Troelsgravsen uses the driver in his SB Acoustics article here: SBAcoustics-61-NAC
If you haven't seen the article it may prove useful reading, unfortunately crossover values are not given but you could look up the SB Acoustics Bromo kit pages for component clues for a 4th order bass driver crossover should you need to tweak in the future.
I am sure the Sb will sound good in a sealed enclosure and if near the wall you will get useful room gain anyway. The tweeter has ferrofluid cooling and can work down to 2Khz or so, this robustness and the fact that the castle crossover was designed (I am guessing) for a 2.5-3.0 Khz crossover means it will be safe.
The harshness or excess you hear could be removed by the correct attenuation and crossover frequency for the tweeter or it could be an artefact of the bass mid metal cone resonance in the high Khz range. Troelsgravsen uses the driver in his SB Acoustics article here: SBAcoustics-61-NAC
If you haven't seen the article it may prove useful reading, unfortunately crossover values are not given but you could look up the SB Acoustics Bromo kit pages for component clues for a 4th order bass driver crossover should you need to tweak in the future.
My input is that tweeter normally measure better regarding edge diffraction, if tweeter is positioned close to the top of the baffle. Depending if you Dont care for uniform polar on both side, offsetting the tweeter is the way to go.
You can try to simulate in the free tool Edge.
You can try to simulate in the free tool Edge.
Thanks for the input.
I have both tweeters offset differently for L and R but I take on board the comments about better nearer the top. I probably won't be moving them now as also would mean moving the SB17 up to keep CTC close.
I do actually have the XO schematic for the Troels design. I don't know how I ended up with it. It is on one of the images in my 'download' folder of many images of schematics I have.! Safe to say I will not share it.
I see the SB Bromo crosses at 3k. I was hoping to do it a bit lower. We will see how they measure and where the distrotion is. Should have some graphs at the weekend.
I have both tweeters offset differently for L and R but I take on board the comments about better nearer the top. I probably won't be moving them now as also would mean moving the SB17 up to keep CTC close.
I do actually have the XO schematic for the Troels design. I don't know how I ended up with it. It is on one of the images in my 'download' folder of many images of schematics I have.! Safe to say I will not share it.
I see the SB Bromo crosses at 3k. I was hoping to do it a bit lower. We will see how they measure and where the distrotion is. Should have some graphs at the weekend.
An interesting day yesterday with the morning spent with member chris661...socially distanced of course...for him to use his expertise and equipment to measure my speakers.
Chris is a very knowledgeable guy, being a sound engineer by profession. If you are anywhere in the vicinity of South Yorkshire/ Derbyshire you could do much worse than employ his services if you so require!
Anyway..we did all the measurements needed to see what the speakers were doing and to either fine tune the XO or start over with a new one. I think Chris was reasonably impressed with the raw drivers FRs, giving hopefully an easy ride to the XO design. We had a 5db rise around 5k which seemed to be from the SB17 and a peak in the inpedance at 9.5k which I think was from the box resonance.
Chris was using some clever digital amps with software control so he could EQ the 5k flatter so I could listen to them and hear the difference. The flatter response was not subtle. Initially I thought I preferred it as was before, but this was a short demonstration. I could see how the 5k peaky response could get tiring to listen to.
Chris drew up a quick XO scheme for me to play with but it looks good to me. I am trying to attach the frd and zma files incase anyone wanted to have a look at it for me also. No worries if not.
Some interesting points; when we did the impedance sweep I had forgotten to put the stuffing back in and we saw some small peaks. Reshuffled and the peaks were gone apart from the 9k one but the SB17 should be pretty well out of the picture by then.
The tweeter had the impedance peak at 720Hz which is bang on the 722hz that the DS shows. And the SB17 betrayed its very low Le with a nice and flat imoedance sweep up from resonance which I tjink was 60Hz or so in the sealed box.
An enlightening experience and now to have a play with Xsim !
Chris is a very knowledgeable guy, being a sound engineer by profession. If you are anywhere in the vicinity of South Yorkshire/ Derbyshire you could do much worse than employ his services if you so require!
Anyway..we did all the measurements needed to see what the speakers were doing and to either fine tune the XO or start over with a new one. I think Chris was reasonably impressed with the raw drivers FRs, giving hopefully an easy ride to the XO design. We had a 5db rise around 5k which seemed to be from the SB17 and a peak in the inpedance at 9.5k which I think was from the box resonance.
Chris was using some clever digital amps with software control so he could EQ the 5k flatter so I could listen to them and hear the difference. The flatter response was not subtle. Initially I thought I preferred it as was before, but this was a short demonstration. I could see how the 5k peaky response could get tiring to listen to.
Chris drew up a quick XO scheme for me to play with but it looks good to me. I am trying to attach the frd and zma files incase anyone wanted to have a look at it for me also. No worries if not.
Some interesting points; when we did the impedance sweep I had forgotten to put the stuffing back in and we saw some small peaks. Reshuffled and the peaks were gone apart from the 9k one but the SB17 should be pretty well out of the picture by then.
The tweeter had the impedance peak at 720Hz which is bang on the 722hz that the DS shows. And the SB17 betrayed its very low Le with a nice and flat imoedance sweep up from resonance which I tjink was 60Hz or so in the sealed box.
An enlightening experience and now to have a play with Xsim !
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They sound great to my ears. I suppose the LF room gain helps mask the 5k rise when actually listening to them in my room. I shall have a tinker with the XO and see what I prefer.
I love the bass these sealed boxes produce. No they maybe don't reach as low as they could ported but I do like sealed bass sound.
I love the bass these sealed boxes produce. No they maybe don't reach as low as they could ported but I do like sealed bass sound.
I would like to repeat the project of floorstanding speakers with two SB17NBAC35-8 and an SB or Peerless aluminum tweeter.
Here is an interesting project, but in it a fabric tweeter SB29SDAC-C000-4.
SB29SDAC-C000-4 + 2xSB 17NBAC35-8 - fox 2.5 - projekt by YB audio & valiant
I also saw that the SB29SDAC-C000-4 datasheet is very similar to the beryllium SB29BAC-C000-4 - how are they interchangeable? I am looking for FRD and ZMA files for these two tweeters to compare in a simulator.
Sorry for my English.
Here is an interesting project, but in it a fabric tweeter SB29SDAC-C000-4.
SB29SDAC-C000-4 + 2xSB 17NBAC35-8 - fox 2.5 - projekt by YB audio & valiant
I also saw that the SB29SDAC-C000-4 datasheet is very similar to the beryllium SB29BAC-C000-4 - how are they interchangeable? I am looking for FRD and ZMA files for these two tweeters to compare in a simulator.
Sorry for my English.
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Sorry for not replying Dreew and there is no need to apologise for your English. It is massively better than my Moldovian!
I would think the designs you are looking at would perform very well.
On my project I now have nearly all the components to make the crossovers. A bit of a mish mash of capacitors but they are all good value in my book. A mix of Russian and Ducati motor run. Just waiting on correct values of resisitors.
Been trying to sort the layout. !
I would think the designs you are looking at would perform very well.
On my project I now have nearly all the components to make the crossovers. A bit of a mish mash of capacitors but they are all good value in my book. A mix of Russian and Ducati motor run. Just waiting on correct values of resisitors.
Been trying to sort the layout. !
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I have made a couple of 2 way speakers with these same tweeters. They are excellent sounding and a great value. I used them with a Peerless NE180W in one case and Eminence CX-8 (sans coax CD).
I sure wish I'd bought more when CPC here in the UK had them for £15 each! They seem easy to work with.
So I made a crossover! 'Big deal' I hear you cry! Well I learned that I am not so good at making physical layouts from schematics....took me hours to decide where things should go. They aren't finalised hence the clips. Rain forecast tomorrow so hopefully will build the second one.!
Bit of a mish mash of caps but the prices of the Russian and motor run caps got my attention for this my first proper build.
I bought some custom wound air coils which are nice...but a pity I ended up with the thicker diameter wired one on the Hf circuit.!
Bit of a mish mash of caps but the prices of the Russian and motor run caps got my attention for this my first proper build.
I bought some custom wound air coils which are nice...but a pity I ended up with the thicker diameter wired one on the Hf circuit.!
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if you still hear «brightness», it may be that the drivers need burn in , or the crossover components are not of best quality/match up for the rest of the system. capacitors are the most impactful, but resistors also have their «own sound». Also, maybe they are so revealing that they amplify the weaknesses of the source chain...?
good to hear the SB woofer sounds good, they are my next drivers to try on my list, to compare to dayton rs225, in the rs225+10f8424 speakers
good to hear the SB woofer sounds good, they are my next drivers to try on my list, to compare to dayton rs225, in the rs225+10f8424 speakers
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Jimk04,
Congratulations on your first XO! Wago clips are the way-2-go! Here’s my latest developmental XO. Once I like the sound I either solder it P2P, or use my basic XO board from the 10F/RS225. Seems to work for most 2way XO’s I have developed.
My crossovers tend to look like this:
They say, “when your only tool is a hammer, everything looks like a nail”!
Congratulations on your first XO! Wago clips are the way-2-go! Here’s my latest developmental XO. Once I like the sound I either solder it P2P, or use my basic XO board from the 10F/RS225. Seems to work for most 2way XO’s I have developed.
My crossovers tend to look like this:
They say, “when your only tool is a hammer, everything looks like a nail”!
@pidesd. Thanks for the input. They have had a fair time running now so I think the drivers will have atleast had their initial run in phase. They are used everyday as they are the main system and also for the TV.
The main 'hifi' source however is an Ian Canada streamer with various salas psus and a Salas DCG3 pre amp.
Cheers XRK! The wagos are indeed handy until i finally implement. I read recently of one diyer and his proto XOs he built using temporary crocodile clips and they injected distortion into the system.? Measurable maybe but hear able?!
One thing I shall comment hear...my XO scheme doesn't have any BSC. My baffles are 250mm wide so not a particularly narrow cabinet. The bass with room gain seems good most of the time but maybe I shall have a trial with bsc.
When I sim'd a BSC network I actually got the LF to decrease not increase. Where do I put the BSC...on the amp outputs so the whole system sees it?
Thanks
The main 'hifi' source however is an Ian Canada streamer with various salas psus and a Salas DCG3 pre amp.
Cheers XRK! The wagos are indeed handy until i finally implement. I read recently of one diyer and his proto XOs he built using temporary crocodile clips and they injected distortion into the system.? Measurable maybe but hear able?!
One thing I shall comment hear...my XO scheme doesn't have any BSC. My baffles are 250mm wide so not a particularly narrow cabinet. The bass with room gain seems good most of the time but maybe I shall have a trial with bsc.
When I sim'd a BSC network I actually got the LF to decrease not increase. Where do I put the BSC...on the amp outputs so the whole system sees it?
Thanks
The BSC for me is usually implemented as part of the crossover but generally resides on the woofer filter. It is the first main coil that performs the low pass function. Strap a resistor in parallel with it to shelve the higher frequency response. This one is extreme but I was attempting to copy the response of an LS3/5A which has a downward tilt to the right.
Sorry my comment wasn't clear there....by 'on the amp outputs ' I was referring to the sim in Xsim...I see now that the bsc network you refer to is in the LF circuit which I think I tried and got the lowering of the LF response. I expected it to go up! Or atleast the HF to come down?
I'll try again tonight.
Cheers!
I'll try again tonight.
Cheers!