For you horn guys: What kind of compression driver are you using for high frequencies? Why that choice (if you know...)

the sound of Tao

Well-Known Member
Jul 18, 2014
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#41
Thanks Mark, I was actually wondering about having to do something about the short leads on the Duelunds... nice pick up.

I am really surprised at the level of improvement by just a few components in the crossover. If I’d done something quite significant like upgraded the 805s to Acmes in the LM and got this level of improvement I’d have been very happy.

Could end up going with the Duelunds in both the horn cap and coupling caps in the LM SET the way it’s going... maybe ultimately go through and do both.

Many thanks for the advice.
Cheers
Tao
 

Sablon Audio

Industry Expert, VIP Donor
May 22, 2015
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#42
Tao, given the choice I would put full Dueland caps into the LM but best to check dimensions and space available. Iirc they use 0.47uf. They really are fantastic caps, my faves, and once sampled it is hard to accept lesser specimens. Are you familiar with the humble hifi cap test blog? Is a great reference.
 

morricab

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Apr 25, 2014
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#43
Pap horn crossover upgrade part 2 cont’d.

After just over a month (probably 3 weeks with the Pap horns in and the other fortnight with the big red Harbeths in rotation) the first cap upgrade in the crossovers has shaped up beautifully. The last few days the benefits went even past the essential sonic improvements and got into a new level of natural nuance and an added even more unmissable musicality in mids and up top. Really started to turn into something I’ve not really experienced before, a quicksilver and more clear liquidity that has stepped even further beyond senses of confinements from electro mechanical process... even more than I thought was possible.

Given how long caps can traditionally take to settle in and form up I think there’s possibly more improvement left in part 1 of the horn crossover upgrade.

So I figure nows the time for upgrade part 2 (or perhaps path 2) and have just put in the two lovely copper shielded pathaudio resistors into the R2 position in the pap crossover.

Just playing the first album now and at the risk of sounding like I’m over the moon well, I’m well fairly well and truly beyond that moon. The first notes were accompanied by some wide eyed expressions and a muttering of some joyous obscenities of genuine surprise.

Just sounding smooooth and effortless, the bass just got a nice extra bit of much useful added tautness AND fullness. Much appreciated especially for the pap horn after always having the bass happy harbys as it’s system sound comparison. Bass is more dynamic already. Drums are just sounding more incisive and with an even more realistic punch and timbre. It’s like they’ve just learnt some bass tricks from the Harbys and just stepped a little closer in that area. That is a great outcome for the OB horns.

There’s also just a bit of lowered noise floor that I really wasn’t expecting. The midbass got just a bit of tuneful extra shove in it as well but certainly not forced, just a might more attack or confidence maybe... but smooooth. Balance is a bit more bottom up now (perfecto) but this is just after the resistor install and some 20 minutes play time so think there’ll very reasonably be further improvement ahead.

The R2 resistor had the very cheapest and lowest spec’d part in the entire crossover in it, a plain Jane stock base mundorf resistor so its now got one of the best resistors available in for the job. Think the Pathaudios were about $30 USD a piece from memory so very much a real no brainer improvement already.

Still have the Duelund cast silver bypass caps to go in but I might wait till the Mundorf Evo supremes are well and truly settled. Exciting times ahead :)

Thinking some Elrogs and Acmes are next in line as a lift for the LM SET now that I’ve sorted through the speaker upgrades for the Pap trio horn.
Thanks for the update. I have been contemplating a crossover upgrade on my Odeons as they have an outboard xover, but I was always just enjoying the sound so much I didn’t go there...strange as I am no stranger to DIY (I have designed and built three different speakers, modded other speakers and built several amp kits). Now, you are inspiring me to open the boxes and go to work :D!
 

the sound of Tao

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Jul 18, 2014
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#44
Yes, the humble hifi cap blog is a marvel Mark. Will definitely have a look into going into the LM with the Duelunds...maybe I should try some Duelund cast silver tin caps

It does feel great when you do a smallish upgrade and get something quite surprising and special out of it. The last month has been quite a transformation for the pap horns. It’s all sounding bigger scaled, richer, more focussed, bolder and more confidently alive.

Makes you feel like getting in and playing even more. Have even been thinking about exploring another horn setup as this is going so well. I do really love the shape of the Autotech Iwata horns :)
 
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the sound of Tao

Well-Known Member
Jul 18, 2014
1,768
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#45
Thanks for the update. I have been contemplating a crossover upgrade on my Odeons as they have an outboard xover, but I was always just enjoying the sound so much I didn’t go there...strange as I am no stranger to DIY (I have designed and built three different speakers, modded other speakers and built several amp kits). Now, you are inspiring me to open the boxes and go to work :D!
You definitely should Brad, that humble hifi cap blog that Mark mentioned is great.
 

morricab

Well-Known Member
Apr 25, 2014
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#47
Yes, the humble hifi cap blog is a marvel Mark. Will definitely have a look into going into the LM with the Duelunds...maybe I should try some Duelund cast silver tin caps

It does feel great when you do a smallish upgrade and get something quite surprising and special out of it. The last month has been quite a transformation for the pap horns. It’s all sounding bigger scaled, richer, more focussed, bolder and more confidently alive.

Makes you feel like getting in and playing even more. Have even been thinking about exploring another horn setup as this is going so well. I do really love the shape of the Autotech Iwata horns :)
I have also been looking at Iwata horns coupled to a TQWT bass design. I would maybe use a Supravox 8 inch driver for the lower mids coupled to the horn at around 800hz and dual 12 inchers in the bass TQWT.
 

the sound of Tao

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Jul 18, 2014
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#48
I did have some thoughts a while back about doing something with some of the Supravox field coils. Look forward to you going down that road. Could be a great path to take.

I was thinking of a couple of options with the Iwatas somewhere down the track. But I’ve currently got a few more speakers than setups so I’d have to make some choices about what to hold on to. The pap horns are certainly not leaving any time that I can imagine.
 

Dookie182

New Member
Dec 9, 2019
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#49
May I Ask what is the compression driver model uses in your PapHorn1 loudspeakers? And did you ever consider trying something else?
Beat regards
 

the sound of Tao

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Jul 18, 2014
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#50
May I Ask what is the compression driver model uses in your PapHorn1 loudspeakers? And did you ever consider trying something else?
Beat regards
It’s apparently one developed specifically for pureaudioproject (not sure by who) but it does look very similar in design approach and build to the BMS CDs though can’t say absolutely for sure.

It’s a 1.4inch compression driver and I’m thinking about getting in the 1.4 inch BMS HE coaxial CD and seeing how that goes in it’s place though I do love really the overall coherence and tonal balance of what I have at the moment. Am thinking if I can extend down below a bit with adding a pair of OB subwoofers also then I can then shift to the BMS coaxial CD which reaches further up top so in the end maintain that right tonal balance. Given I will be able to control the level of the sub as well I should hopefully be able to tune it to a good balanced outcome.

It will be a new year project though as I’m so happy with the Paps as they are modified now that I’m thinking that I may well not need anything more really. May just work some more with what I have first and looking forwards to some nice valve upgrades before building anything new.
 
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morricab

Well-Known Member
Apr 25, 2014
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#51
It’s apparently one developed specifically for pureaudioproject (not sure by who) but it does look very similar in design approach and build to the BMS CDs though can’t say absolutely for sure.

It’s a 1.4inch compression driver and I’m thinking about getting in the 1.4 inch BMS HE coaxial CD and seeing how that goes in it’s place though I do love really the overall coherence and tonal balance of what I have at the moment. Am thinking if I can extend down below a bit with adding a pair of OB subwoofers also then I can then shift to the BMS coaxial CD which reaches further up top so in the end maintain that right tonal balance. Given I will be able to control the level of the sub as well I should hopefully be able to tune it to a good balanced outcome.

It will be a new year project though as I’m so happy with the Paps as they are modified now that I’m thinking that I may well not need anything more really. May just work some more with what I have first and looking forwards to some nice valve upgrades before building anything new.
Maybe I suggested this to you already but give the Beyma CP755Ti a try. Not super expensive but really good with low distortion and basically no breakup despite being a metal diaphragm. The Radian Pb745 would be another interesting one but pricey in Be form (Al one not so bad). What is the Xover freq?
 

the sound of Tao

Well-Known Member
Jul 18, 2014
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#52
Maybe I suggested this to you already but give the Beyma CP755Ti a try. Not super expensive but really good with low distortion and basically no breakup despite being a metal diaphragm. The Radian Pb745 would be another interesting one but pricey in Be form (Al one not so bad). What is the Xover freq?
Brad I read that it (from memory) crosses up to the horn around 450hz so the 15 inch woofers are working up quite high. Was thinking maybe adding either 2 additional 15 inch woofers as a 2.5 way and then crossing the additional new ones much lower OR just building an independent pair of OB subs tho still using the same 15 inch neodymium woofers but paired and maybe even as isobaric in a magnet to magnet arrangement. As you can tell I’m still in explore mode. But if I design it in a modular way and get some laminated bamboo baffles made up I can try both ways. I had all my kitchen benchtops made up by a joiner in giant slabs of laminated bamboo and they do a furniture grade finish so am looking forward to trying it for the OBs.
 

morricab

Well-Known Member
Apr 25, 2014
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#53
Brad I read that it (from memory) crosses up to the horn around 450hz so the 15 inch woofers are working up quite high. Was thinking maybe adding either 2 additional 15 inch woofers as a 2.5 way and then crossing the additional new ones much lower OR just building an independent pair of OB subs tho still using the same 15 inch neodymium woofers but paired and maybe even as isobaric in a magnet to magnet arrangement. As you can tell I’m still in explore mode. But if I do it as a modular way and get some laminated bamboo baffles made I can try both ways.
Ok, that is a bit low for most 1.4 inch CDs. The Beyma and Radian are really good only to about 600Hz. 450 should still be fine for a good 15 incher and I have seen them go as high as 1khz.
 

Dookie182

New Member
Dec 9, 2019
2
2
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38
#54
Ok, that is a bit low for most 1.4 inch CDs. The Beyma and Radian are really good only to about 600Hz. 450 should still be fine for a good 15 incher and I have seen them go as high as 1khz.
It’s apparently one developed specifically for pureaudioproject (not sure by who) but it does look very similar in design approach and build to the BMS CDs though can’t say absolutely for sure.

It’s a 1.4inch compression driver and I’m thinking about getting in the 1.4 inch BMS HE coaxial CD and seeing how that goes in it’s place though I do love really the overall coherence and tonal balance of what I have at the moment. Am thinking if I can extend down below a bit with adding a pair of OB subwoofers also then I can then shift to the BMS coaxial CD which reaches further up top so in the end maintain that right tonal balance. Given I will be able to control the level of the sub as well I should hopefully be able to tune it to a good balanced outcome.

It will be a new year project though as I’m so happy with the Paps as they are modified now that I’m thinking that I may well not need anything more really. May just work some more with what I have first and looking forwards to some nice valve upgrades before building anything new.
Thanks à lot for the input. I'll have à look on those then. I'll be glad To hear vos things are evolving on your side. Beat regards.
 

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