dubplate007,
If you want to try out an internet derived crossover ( with all its failings ) here's one ( I traced the available product info and then threw it all into XSim );
This will only be a starting point because you have one woofer pointing up+ away from the listener ( this crossover is much more applicable to a straight-forward MTM setup > though without any BSC applied ).
All this means you'll need to turn down the level of the tweeter by increasing the value of R3 ( likely doubling it at the very least ).
This network closely follows the topology ( fwiw ) of the one seen in the pic that I posted ( albiet adjusted for the lower impedance drivers ).
The most significant change is the addition of a notch filter on the twin woofers ( though it might not be needed if the real "tested" response ends up being flatter than the product sheet indicates ).
- L2+C2+R2 form the PEQ notch centered around @ 1400hz .
- R2 will adjust ( the notch depth ) by varying the 5R value upwards to as high as 10 ohms ( iow; 10 ohms gives less cut ).
Some overall resistance needs to be added somewhere to bring the minimum impedance up to at least 4 ohms ( maybe small gauge wiring for the woofers could be used ).
- Currently this network is a bit of an amp killer dipping to 3 ohms ( so beware ).
If you want to try out an internet derived crossover ( with all its failings ) here's one ( I traced the available product info and then threw it all into XSim );
This will only be a starting point because you have one woofer pointing up+ away from the listener ( this crossover is much more applicable to a straight-forward MTM setup > though without any BSC applied ).
All this means you'll need to turn down the level of the tweeter by increasing the value of R3 ( likely doubling it at the very least ).
This network closely follows the topology ( fwiw ) of the one seen in the pic that I posted ( albiet adjusted for the lower impedance drivers ).
The most significant change is the addition of a notch filter on the twin woofers ( though it might not be needed if the real "tested" response ends up being flatter than the product sheet indicates ).
- L2+C2+R2 form the PEQ notch centered around @ 1400hz .
- R2 will adjust ( the notch depth ) by varying the 5R value upwards to as high as 10 ohms ( iow; 10 ohms gives less cut ).
Some overall resistance needs to be added somewhere to bring the minimum impedance up to at least 4 ohms ( maybe small gauge wiring for the woofers could be used ).
- Currently this network is a bit of an amp killer dipping to 3 ohms ( so beware ).
Attachments
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Hi Karl
I managed to trace the original harlech crossovers ,on the bass section it is a 1.50 mh inductor and a 10 uf cap used as a flattening zobel on the 2nd pole which flattens the impedance of the bass units the 1 ohm resistor in parallel with the 10 uf cap apparently modulates the impedance to make the units when run in parallel look more like 5 ohms than 4 ohms .......i was wondering if you could run that circuit with the monacor units in your xsim program and see what adjustments can be made to suit the monacor units?
many thanks in advance
I managed to trace the original harlech crossovers ,on the bass section it is a 1.50 mh inductor and a 10 uf cap used as a flattening zobel on the 2nd pole which flattens the impedance of the bass units the 1 ohm resistor in parallel with the 10 uf cap apparently modulates the impedance to make the units when run in parallel look more like 5 ohms than 4 ohms .......i was wondering if you could run that circuit with the monacor units in your xsim program and see what adjustments can be made to suit the monacor units?
many thanks in advance
dubplate007,
If you want to see why the original crossover won't work well with your new drivers then you'll need to download Xsim download_"free passive crossover simulator" and then take play with the following attached (zipped) file .
Just "right-click" on any passive element, chose "Tune" and change the values to what matches your existing crossover.
"Right-Clicking" also includes some other choices such a "short" & "open" which when chosen will allow you to bypass or take a string of elements completely out of circuit.
Have fun!
If you want to see why the original crossover won't work well with your new drivers then you'll need to download Xsim download_"free passive crossover simulator" and then take play with the following attached (zipped) file .
Just "right-click" on any passive element, chose "Tune" and change the values to what matches your existing crossover.
"Right-Clicking" also includes some other choices such a "short" & "open" which when chosen will allow you to bypass or take a string of elements completely out of circuit.
Have fun!
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Hi all ,just to clarify ,a friend and i managed to work out exactly what the original harlech crossovers do ,to anyone with doubts and looking to replace the original drive units with the Monacor sph 135 c or kevlar equivalent ,these will work fine with the original crossover ,although not designed for those woofers ,i can report minimal change in impedance and or characteristics apart from the monacors are a bit more punchy in the bass,and if honest a smidgen darker than the original woofers ,but that is down to the drive units not the crossover
After all the agonising, the fix to the broken woofer was easy enough...
Best use the replacement Carbon Fibre 5" Monacor SPH135C in the top firing position:
Bit of a typical bump at around 1.4kHz there, and some typical Kevlar or Carbon Fibre breakup at 6kHz. Sort of breakup thing polycones are better at.
The crossover is basic enough, whatever the exact details. Around 2.5kHz XO. You would need quite a bit of work to get it to monitor flatness, but most people can live with these imperfections. Actually a speaker that works with the room to get a reasonable power response IMO. I suppose it might be a bit thin on vocals in Castle's layout.
The red resistors are adjustable, though the 1R does next to nothing anyway. The 2.2R will adjust tweeter brightness.
Best use the replacement Carbon Fibre 5" Monacor SPH135C in the top firing position:
Bit of a typical bump at around 1.4kHz there, and some typical Kevlar or Carbon Fibre breakup at 6kHz. Sort of breakup thing polycones are better at.
The crossover is basic enough, whatever the exact details. Around 2.5kHz XO. You would need quite a bit of work to get it to monitor flatness, but most people can live with these imperfections. Actually a speaker that works with the room to get a reasonable power response IMO. I suppose it might be a bit thin on vocals in Castle's layout.
The red resistors are adjustable, though the 1R does next to nothing anyway. The 2.2R will adjust tweeter brightness.
Attachments
Afternoon All,
Firstly i wanted to put a shout out of gratitude to the community of support and advice on this forum. Specifically on this thread; I've embarked on the path of owning a pair of Castle Harlech S1. Here's what i've learned thus far;
The original S1 woofer drivers seem to be UV damage prone, it is common for the translucent white polyprop cones to crack and shatter.
I have two good ones and two that have broken cones.
DC resistance (Re) is ~11.5 ohms, they're wired in parallel to the crossover. I assume these are a 16ohm nominal driver.
The woofers test as follows:
fs (hz) 44.65
Qts 0.34
Vas (litres) 15.84
SPL (1W/1m) 87.85
Re (ohms) 11.05
Qms 5.91
Qes 0.36
Le (mH) 1.69
Mms (grams) 10.55
Cms (mm/N) 1.20
BL 9.57
Zmax (ohms) 193.70
I'm at a loss with the array of candidate replacements, any recommendations? I am comfortable with doing some cabinet work. I'm tempted to replace all 4 woofers, unless replacing two won't adversely affect the xover or how the TL enclosure works.
Which T/S paramaters should i be matching as a priority?
Any learned advice gratefully received.
Rob
Firstly i wanted to put a shout out of gratitude to the community of support and advice on this forum. Specifically on this thread; I've embarked on the path of owning a pair of Castle Harlech S1. Here's what i've learned thus far;
The original S1 woofer drivers seem to be UV damage prone, it is common for the translucent white polyprop cones to crack and shatter.
I have two good ones and two that have broken cones.
DC resistance (Re) is ~11.5 ohms, they're wired in parallel to the crossover. I assume these are a 16ohm nominal driver.
The woofers test as follows:
fs (hz) 44.65
Qts 0.34
Vas (litres) 15.84
SPL (1W/1m) 87.85
Re (ohms) 11.05
Qms 5.91
Qes 0.36
Le (mH) 1.69
Mms (grams) 10.55
Cms (mm/N) 1.20
BL 9.57
Zmax (ohms) 193.70
I'm at a loss with the array of candidate replacements, any recommendations? I am comfortable with doing some cabinet work. I'm tempted to replace all 4 woofers, unless replacing two won't adversely affect the xover or how the TL enclosure works.
Which T/S paramaters should i be matching as a priority?
Any learned advice gratefully received.
Rob
Hi Dubplate, would you be able to share a diagram or schematic of the original crossovers, and what you did to them to adapt for the Monaco’s 135carbon drivers if anything? I see that you’ve had a couple of suggestions on here using Xsim.
My electronics knowledge is patchy and I can’t quite figure out how replacing my original ~12ohm drivers with 8ohm nominal (5-6ohm DC) drivers won’t have an effect on SPL or efficiency… or ’balance’ of levels with the tweeter.
Keen to learn from your experience.
Rob