Wow 12!
I'm still learning to tame my DIY effort, so not qualified to comment more than I've got quite good results with DSP X/O DAC setup and 3 amps.
It was relatively easy setting up to sound pretty good and loud.
Getting the phase as first as possible is a bigger ask.
I went too far with the PEQs a couple of times.
I will sometime this summer be trying then outside hooked up to a Behringer DCX 2496 for control and 3 PA amps.
I might be adding a 2nd 12" LF driver and even a couple more MF drivers, as higher efficiency will be needed than in my hifi room.
I will follow your story with interest.
Yes, before the current iteration, there were problems.
https://forums.prosoundweb.com/index.php?topic=101186.40
“OR....as in my case, you could just have almost any male singer sing through the P.A. and there would be plenty of immediately noticeable distortion. Not so difficult to reproduce really.”
Yeah, it would have been way way easier to find the problem if all they all had a problem. It wasn’t until Ivan was able to make one of the new boxes do it that it could be reproduced “on the bench” for troubleshooting. My boxes (older ones) wouldn’t do it...As Murphy’s law would dictate, the “last” change I made to the crossover (the revision which caused this to be an issue) was one which had a small favorable impact in the response / phase and electrical power handling was added (and I remember thinking, “this is small it won’t be an issue”) near the end of the revision process..Anyway, again I am sorry there was a problem with this, for me it serves as a reminder about making “small changes” to a previously stable system..
The bottom line is that with conventional DSP filters, one follows a similar transfer function as the passive unit with the advantages that one isn’t concerned with the load impedance curve (a major hassle in designing passive filters) and one has time delay much “EQ” available, each point of which costs 2 or 3 parts in a passive version and time delay only possible by moving the drivers..
Best,
Tom Danley"
The only advantage of a passive crossover is using a single amp channel and no external processing, there are no sonic advantages.
The potential fidelity/phase benefits of using active are many, and amplifier and processing cost has come down to the point where three-way active may be less expensive than the passive components that can't perform as well.
Art
This evening I focused on the BMS 4550 compression drivers in the SH50s.
I've been having a bit of a hard time comparing them with the Vitavox S2s (latest issue diaphragms, fully refurbished) on Le Cléac'h horns.
Things like piano and female vocal just not smooth enough..
I searched for tuning compression drivers on this place and wasn't disappointed😀
I focused on the FR peaks when looking at 1/16 or more smoothing - much higher detail than I usually care to look.
I cut the worst peaks on each BMS channel and had a listen. Much smoother but not dulled.
Could Inc the SPL a bit to taste, for more dynamics, without them grating or setting my ears on edge.
It's a much nicer listen.
Then did the same on the MF (Celestion 5"ers).
One thing I noticed in the measurements answered one of my construction questions...!
Comparing the RH MF (where I had dished the taps under the drivers), when looking in that sort of detail gave quite a bit smoother FR curve than the LH channel (just straight holes through)..
The difference is not audible to me, but it is on the plots.
I will dish them next time I have the thing apart for some reason.
So that's cleared that up for me🙂
I've been having a bit of a hard time comparing them with the Vitavox S2s (latest issue diaphragms, fully refurbished) on Le Cléac'h horns.
Things like piano and female vocal just not smooth enough..
I searched for tuning compression drivers on this place and wasn't disappointed😀
I focused on the FR peaks when looking at 1/16 or more smoothing - much higher detail than I usually care to look.
I cut the worst peaks on each BMS channel and had a listen. Much smoother but not dulled.
Could Inc the SPL a bit to taste, for more dynamics, without them grating or setting my ears on edge.
It's a much nicer listen.
Then did the same on the MF (Celestion 5"ers).
One thing I noticed in the measurements answered one of my construction questions...!
Comparing the RH MF (where I had dished the taps under the drivers), when looking in that sort of detail gave quite a bit smoother FR curve than the LH channel (just straight holes through)..
The difference is not audible to me, but it is on the plots.
I will dish them next time I have the thing apart for some reason.
So that's cleared that up for me🙂
Hi astanway,
I saw those for sale too. Frankly, I think the SH50 without the passive xover is what I'd want.
I don't think there is ANY disadvantage to not having the passive xover. It's a fine piece...but still...
....... I say ditch the passive xover and never look back
@mark100 disadvantages being needing 3 amp channels per speaker and separate DSP box (complexity and $$$). In general I can understand why there’s no point in passive for DIY. But if it already exists in the stock model, I’m not certain that there are known shortcomings that an external crossover could fix. Art’s post referenced an issue from 15 years ago that looks like it got addressed in a further iteration. It’s a tough call imo.
The frequency response can easily be improved over the passive crossover with DSP, as can the phase response, especially if FIR processing is included.
I think that this particular subject has gone far enough without first seeking another (new) thread to discuss it to the detail you apparently think is sufficient. While I do have more information to share on this subject, I don't believe that it's appropriate to do it in this thread.
Please open your own thread to ask these questions, and I'll be happy to join in.
Chris
Hi, yeah sorry, i forget not everyone shares my complete focus on achieving best sound quality possible, at the expense of other significant real world factors.
It does look like any issues with the passive xover were solved back then. And don't know of anyone whose had direct experience with both passive and active versions, to ask for comparisons. So how significant are any possible shortcomings??? Who knows....
I have seen that Tom D used a global FIR overlay on top of his SH-50s he keeps at home.
And it's pretty clear looking at the the SH-50's response graphs, & Erin's measurements, etc,..... that there is room for valid corrections beyond the passive tuning.
When Add in the known benefits of multi-amping......well, I guess i'm describing why I'd be willing to go thru the complexity and $$ on such a box.
Liking to experiment and I expect some might roast me for this..🙂
I lasted just over 2 weeks with the sound of the BMS 4550 1" drivers in the conical SH50 alikes.
Don't get me wrong, on a dance floor, or a wedding it would work just fine.
Some things sounded good.
Personally for me - long term hifi listening it just lacked that emotionally epic, draw you in performance and sound I get from my Vitavox S2s on the Le Cléac'h horn.
So here's what I'm listening to now 😂
Subs - Still the long tapped horns
LF and MF the SH50 alike Synergy horns
HF- S2s / Le Cléac'hs
HF+ Raal Lazy ribbons
I went back to my usual implementation of crossovers that are chosen for similar slopes to give good phase aligned overlaps (not trying to flat phase adjust outside of the Synergy horn).
To sum up, I like the LF bass performance from the Synergy, the MF is fine enough too (for now?).
Now I have the S2 magic back too, and if my daughters come and listen they will not miss the Raal HF+.
Also, I'm not listening in a big cinema room where even sound coverage is important.
What next? Who knows
I lasted just over 2 weeks with the sound of the BMS 4550 1" drivers in the conical SH50 alikes.
Don't get me wrong, on a dance floor, or a wedding it would work just fine.
Some things sounded good.
Personally for me - long term hifi listening it just lacked that emotionally epic, draw you in performance and sound I get from my Vitavox S2s on the Le Cléac'h horn.
So here's what I'm listening to now 😂
Subs - Still the long tapped horns
LF and MF the SH50 alike Synergy horns
HF- S2s / Le Cléac'hs
HF+ Raal Lazy ribbons
I went back to my usual implementation of crossovers that are chosen for similar slopes to give good phase aligned overlaps (not trying to flat phase adjust outside of the Synergy horn).
To sum up, I like the LF bass performance from the Synergy, the MF is fine enough too (for now?).
Now I have the S2 magic back too, and if my daughters come and listen they will not miss the Raal HF+.
Also, I'm not listening in a big cinema room where even sound coverage is important.
What next? Who knows
Something like this
https://www.diyaudio.com/community/threads/jean-michel-on-lecleach-horns.140190/post-1770539
With taps and ports 😀
Curved 5" and 12" driver mount adaptors.. noone makes a curved driver basket😂
Would still need a S2 killer - 1000Hz to 20000Hz driver.
TAD2001 or 4001?
Can't see getting a 4 or 5" MF within 1/4 WL of the throat.
I suppose a long exit compression driver with the diaphragm right at the back, like Vitavox S2 and TAD?, count as included in the throat length?
Makes things worse.
There's a reason they are 50 and 60° conicals..
Elliptical closed back, hens teeth, MF drivers😀? Could always seal some up I suppose.
Just musing.
Should hear a real SH60F first perhaps.
Can be hired from £50 a day!
I suppose a long exit compression driver with the diaphragm right at the back, like Vitavox S2 and TAD?, count as included in the throat length?
Makes things worse.
There's a reason they are 50 and 60° conicals..
Elliptical closed back, hens teeth, MF drivers😀? Could always seal some up I suppose.
Just musing.
Should hear a real SH60F first perhaps.
Can be hired from £50 a day!
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In my opinion, the tiny annular diaphragm on a BMS 4550 just doesn't sound very good (compared to a cone driver) crossed below ~1kHz on a conical horn.
Looks like you have enough mid overlap to move the mid/high acoustic crossover up to around 1200Hz, which would make them sound more similar to the Vitavox S2/Le Cléac'h horn.
Putting mid ports in close to the throat in a slow expanding horn like the Le Cléac'h would mess up it's HF response.
Art
Thanks Art. I tried various X/O points in the quest for a pleasing phase plot, but didn't listen to many of them - yet.
I've set it up so I can switch between the S2s / Le Cléac'h + Raals 5 way vs the BMS 4550 and full synergy in a matter of seconds.
I'm trying the old resistor in series trick.
Read about that on a Le Cléac'h discussion and break out thread by Patrick.
10ohm was a bit much, 6.8ohm or as low as 5ohm is nice and more subtle.
I'm trying 1200Hz X/O point for the BMS 4550 at the moment.
Together with the 5ohm resistor it's a more rounded pleasing sound.
Proof that it's the 4550 compression driver stock sound, not so much the horn..
Wonder just how much more pleasing the 4552ND (twice the price) or indeed the 5CN160 used in the SM60F, would be?
I'm enjoying fiddling around with it all.
Not a chore for me.
Sage words about the Le Cléac'h throat and HF messing up..
I've set it up so I can switch between the S2s / Le Cléac'h + Raals 5 way vs the BMS 4550 and full synergy in a matter of seconds.
I'm trying the old resistor in series trick.
Read about that on a Le Cléac'h discussion and break out thread by Patrick.
10ohm was a bit much, 6.8ohm or as low as 5ohm is nice and more subtle.
I'm trying 1200Hz X/O point for the BMS 4550 at the moment.
Together with the 5ohm resistor it's a more rounded pleasing sound.
Proof that it's the 4550 compression driver stock sound, not so much the horn..
Wonder just how much more pleasing the 4552ND (twice the price) or indeed the 5CN160 used in the SM60F, would be?
I'm enjoying fiddling around with it all.
Not a chore for me.
Sage words about the Le Cléac'h throat and HF messing up..
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I've tested and listened to them both, the BMS 4552ND has about -3dB less output below 1kHz than the BMS 4550, but has ~+2dB from 5kHz up. The 4552ND is "brighter".
This graph shows four drivers on the same 13 x13 degree two part conical horn measured on axis outdoors from two meters, with around 1 meter square baffle behind the 300mm x 300mm horn mouth. For a 250Fc horn, the mouth is undersized, so there is more horn "ripple" below 1kHz.
BMS 4550 (50on) is the White trace.
The BMS 4552ND (52on)is the Green trace.
The Eminence 2002 (02on) is the Orange trace.
The 2002 has a 1" exit, 2" titanium dome diaphragm, used in PA cabinets made by Yamaha and many other manufacturers.
The Purple trace is a 3.5" TC9FD "full range driver" using a 1 liter compression chamber and a 2" exit.
This trace was done after the other drivers were evaluated, and is 8 ohms (all others 16 ohms) so the sensitivity may not be accurate by comparison.
I found the TC9FD subjectively to sound cleaner than any compression drivers at high volumes, melted it's voice coil off the former with no sound of distress, while a 3" diaphragm driver well within it's thermal range at the same SPL sounded harsh and IM (Inter Modulation) distorted.
The Purple TC9FD clearly is the winner in output below 600Hz, but with no phase plug, response is erratic above 3kHz.
The Orange 2002 has ~8-10dB more output (~twice as loud!) than the BMS drivers at 400Hz, showing how much less output below 1kHz the BMS have compared to an "average" 1" driver.
The BMS really "shine" above 2kHz, with smooth response up to the 17.5 kHz +6dB peak, response extending past 25kHz. Below 1kHz, not much to write about- more THD and IM than any other drivers I tested.
You could listen to all the compression drivers and many others with audio files in this thread:
https://www.diyaudio.com/community/threads/high-frequency-compression-driver-evaluation.212240/
Art
Nice you folks have such agreeable partners that permit piled up boxes and drivers in the living space……I’d be living in the workshop if I tried that.
How does the Brandi Carlisle song - You and Me on the Rock, go?Nice you folks have such agreeable partners that permit piled up boxes and drivers in the living space……I’d be living in the workshop if I tried that.
"Me out in my garden and you up in your music loft"😂
I've got my own den, she's got a whole plot of land she loves🙂