Troels has two 861 2.5way designs on his website with kits or just crossovers available from Jantzen.
These are much lower priced compared to Troels's regular builds, particularly the SBA kit.
In the UK, I can get parts for the Discovery 861 ( with standard XO) for £650 + some shipping
The SBA -861-PFCR with Superior XO can be put together for £430 + some shipping.
These prices exclude wood, stuffing, etc.
http://www.troelsgravesen.dk/Discovery-861.htm
http://www.troelsgravesen.dk/SBA-861-PFCR.htm
I would appreciate some thoughts on these designs, and whether the Discovery kit is worth the extra.
These are much lower priced compared to Troels's regular builds, particularly the SBA kit.
In the UK, I can get parts for the Discovery 861 ( with standard XO) for £650 + some shipping
The SBA -861-PFCR with Superior XO can be put together for £430 + some shipping.
These prices exclude wood, stuffing, etc.
http://www.troelsgravesen.dk/Discovery-861.htm
http://www.troelsgravesen.dk/SBA-861-PFCR.htm
I would appreciate some thoughts on these designs, and whether the Discovery kit is worth the extra.
I for one do not care for the HDS tweeter, but I would prefer the Discovery midbasses as they are woven fiber. The SB29RDAC is a good tweeter, but I feel it needs Fs comp to not sound buzzy.
I think the Discovery is likely the better sounding buy, and the SBA is higher bang/buck.
I think the Discovery is likely the better sounding buy, and the SBA is higher bang/buck.
I’ve tested these SBA 6.5” cone, and confirm they do not have shorting rings.
For price constrained OEM mass production and sales I think they are a good choice, but for DIY where you time and sweat and labour is significant; why not save up and get something with a better magnet system.
SS Disco has alu shorting ring and Made in Denmark- an incredible deal IMHO.
For price constrained OEM mass production and sales I think they are a good choice, but for DIY where you time and sweat and labour is significant; why not save up and get something with a better magnet system.
SS Disco has alu shorting ring and Made in Denmark- an incredible deal IMHO.
Is the price the only thing that appeals you on those designs, or there are other reasons?
IMHO those are two versions of a flawed concept, with some critical points.
I really don't see the point in a 2.5 way with two completely different woofers, where one is somewhat bass limited by being in a closed box. This means that in the upper bass the two drivers will sum, but lower not and so the bass overall is maybe a little thin. On the converse, the upper mid-bass driver do play some bass and this - as always - is a source of potential distortion on midrange notes. All in all a true 3-way design could solve completely those problems and offer a better midrange - with the same drivers. The only pro of this 2.5 way is the enhanced sensivity with two drivers in parallel.
Another problem is the integration between a tweeter and a 6.5" mid. The crossover point for the Discovery kit is at 2.8KHz, way too high for a good integration between two completely different dispersion characteristics. And using the relatively expensive 9130 tweeter so high doesn't make much sense. On the SBA kit the crossover point between mid and tweeter is not stated, so can't comment for sure.
Another problem is the stepped baffle, just to create a good amount of diffraction, a distortion that seems to be fairly offensive. The stepped baffle is only needed in order to use a LR2 crossover. IMHO a far better approach would have been with a lower point LR4 crossover with drivers close together, or with a tweeter in a waveguide. All diffraction, dispersion and source point problems would disappear. And if 3-way also with a smaller mid.
If I had to choose a closed kit like those, I'd like to see more measurements, in particular off-axis, so I can judge the power response. Here we have nothing, no crossover points and slopes, no off axis behaviour. I see all potential problems, and the fact that those important measurements are missing is at least supicious.
In general I don't like to have to buy boutique crossover components, and the only sensible kit in this vision is the standard version SBA one. If it was a 3-way it could have been a good candidate. But at the price point of the SS Discovery kits, even the lower one, I think there are better behaved 3-way speakers around.
Ralf
I think you are mixing up "wrong" or "problematic" with that you would have chosen another compromise.
Here the goal was to design a potent, yet affordable speaker, with great components and xover parts. A 3-way would have been more expensive, needing more xover parts and also minimized the efficiency and output - as you mention. This is good for tubes. And more area means less distortion,
I am not sure why it is too high, how can we know without playing around with it and listening...
Wilson Audio makes 100,000 USD 2.5-way speakers.... and a lot of other speakers manufacturers such as Dynaudio, Sonus Faber, etc also makes 2.5-way speakers. Obviously, there seem to be people who think it can be a fantastic speaker.
Here the goal was to design a potent, yet affordable speaker, with great components and xover parts. A 3-way would have been more expensive, needing more xover parts and also minimized the efficiency and output - as you mention. This is good for tubes. And more area means less distortion,
Troels write that the 6.5 is super smooth on the baffle... obvisouls the dispersion is different from a small tweeter and a 6.5 inch speaker.
I am not sure why it is too high, how can we know without playing around with it and listening...
I would argue that is not a problem - why is a stepped baffle a problem? It is needed to timealign the drivers with the tweeter. It is there to create a simple crossover that don't interfere more than needed.
Well, the cool thing is that you can just change the speaker and crossover if you don't like it...
maybe you could list them
Well, at least Troels often display his designs at large Audio events as an ambassador for Scanspeak, so they must think he is a pretty good speaker designer...
Here is another who don't like much HDS tweeter. (Other project i have vifa DQ25 and i like that one more)
@wolf_teeth, Any opinions of good sounding soft dome tweeter?
just to be sure, we are talking about this one, right...
https://www.scan-speak.dk/product/d2608-913000/
https://www.scan-speak.dk/product/d2608-913000/
Dublin78 when you listen to a loudspeaker what things grab you., it would be interesting to hear what you are searching for, what do you currently use. How big is the intended room ?
Are you critical of recording technique's and production, do some albums sound really bad, whilst others are fantastic.
Have you built a kit before and done any tweaking, I ask as it is DIY you can tune to your hearts desire without compromising the guarantee.
I haven't heard either of the designs in question and I don't know your musical tastes, so I cannot give you a recommendation. I guess they both can produce a fair amount of bass so i don't think you will be able to get them to close to a corner position which is the case with many larger speakers.
I think they will perform to a good level, you cannot design that many speakers without accruing some knowledge and skill and a large part of the information is their for all to see, he often quotes some resistor values to tune tweeter levels which I imagine is useful for first time builders.
As others have said sometimes you get what you pay for, Wolf Teeth's summing up seems fair. However, buying without an audition is a difficult concept.
Are you critical of recording technique's and production, do some albums sound really bad, whilst others are fantastic.
Have you built a kit before and done any tweaking, I ask as it is DIY you can tune to your hearts desire without compromising the guarantee.
I haven't heard either of the designs in question and I don't know your musical tastes, so I cannot give you a recommendation. I guess they both can produce a fair amount of bass so i don't think you will be able to get them to close to a corner position which is the case with many larger speakers.
I think they will perform to a good level, you cannot design that many speakers without accruing some knowledge and skill and a large part of the information is their for all to see, he often quotes some resistor values to tune tweeter levels which I imagine is useful for first time builders.
As others have said sometimes you get what you pay for, Wolf Teeth's summing up seems fair. However, buying without an audition is a difficult concept.
Well, I absolutely loathe the DQ25. It's awful.
As I look around, I really dig the Seas Titan 27TAC/GB, but it's an alloy metal dome.
If you don't mind the off axis being poorer than conventional, the XT25 and derivatives all sound fantastic.
The SS silk tweeters have it for me. 9900, 9700, and 6630 for the great stuff. Morel makes a good dome mid and tweeter too.
I also like a lot of the Tymphany offerings, but they are slowly disappearing. SS Discovery similar models will still be around though.
The SB26 sounds great, as do a few of the Dayton models.
Thanks of your reply. I have to look seas 27TAC. I have thinked use this tweeter earlier, looks nice. Measures well.
Yes, DQ25 have issues. My 9130 have nicely "air", but lacks of 3d image. And somehow it is more sibilant than my DQ25. Maybe i have crossed 9130 too low. (2.2 khz)
Chalk me up as another who doesn't like the HDS tweeter, crossed around the same as above. Measurements are good, but something is just annoying/sterile about its top end.
re:'I really don't see the point in a 2.5 way with two completely different woofers, where one is somewhat bass limited by being in a closed box' - this gives control over the mid-bass, which is where the magic lies in a speaker.
For the OP, if you don't have the option of forming a preference by hearing the mid-bass drivers, perhaps looking at the Distortion profiles might help, if someone like HI-FI Compass or Audio Heuristics have made measurements of these drivers
For the OP, if you don't have the option of forming a preference by hearing the mid-bass drivers, perhaps looking at the Distortion profiles might help, if someone like HI-FI Compass or Audio Heuristics have made measurements of these drivers
SS D2608-9130 has a ton of upper octave breakup that doesn't show up on a smoothed FR. The fact is most 1" soft domes operate in breakup mode above roughly 10k, but some are better than others at it. I've never been satisfied with the 9130's stale yet vague top end, imaging and lifeless presentation. It falls apart when asked to play its higher end spectrum share of a trumpet at convincing levels. Almost every name brand $40 - $60 one inch soft dome can deal with this.
Hmm... I like the HDS tweet just fine although I do prefer less sparkle, my fave soft dome is the satori dimple dome, so smooth and laid back.
That satori ring rad is a nice tweeter. Doesn't look good on paper in some ways but has a very interesting upper octave signature like some other ring rad soft domes. My issue with these however is the increased midrange HD compared to most common soft domes. The cheap Peerless XT ring rad has very good upper octave performance, but awful lower cutoff distortion, yet many designers push it too hard down low. It just doesn't sound good at all run lower than 2.5k. Its happiest above 3.0k in a small WG, like the visaton one. In this configuration you can have some of the best treble available under 500 bucks and that says alot being a cheap tweeter.
My satori's are crossed at 2k 4th order. The last xt25's I had were in the zaph zd5 and were crossed at 2.5k 2nd order and were very nice as well.
The comments are interesting - from the people who have listened to these two speakers, they all say the Discovery is warmer, while the Satory is more detailed and analytical. I guess each driver works different in different speakers....
Maybe because it is not drivers from the Satori line and this particular RDC tweeter is a little laid back.
I have not heard the Discovery woofers but the littlier FR 10/8424GO with the same material, it is not warm at all, quite neutral and open with some ligth, detailled without being fatiguing.
The tweeter is making a lot on how you hear the harmonics too and what they describe is surely what wolfteeth said above : they experienced the sounding signature of the ScanSpeak tweeter above.
Based on tweeter only I would pick-up the papers with the RDC or the Discos but with a different tweeter according the cut-off. if >2500 somethin from the SB26C line for instance and why not the SB29rdc as well. Alas you quite the option of buying him a Janzen kit if so.
I have not heard the Discovery woofers but the littlier FR 10/8424GO with the same material, it is not warm at all, quite neutral and open with some ligth, detailled without being fatiguing.
The tweeter is making a lot on how you hear the harmonics too and what they describe is surely what wolfteeth said above : they experienced the sounding signature of the ScanSpeak tweeter above.
Based on tweeter only I would pick-up the papers with the RDC or the Discos but with a different tweeter according the cut-off. if >2500 somethin from the SB26C line for instance and why not the SB29rdc as well. Alas you quite the option of buying him a Janzen kit if so.