Re: AP100Z0 Fs
I found that a brand-new driver needed running for a couple of minutes before FS would stabilise. Did you go back and re-check FS? It's possible it was just running in while you were making the measurements.
Two of my drivers have had a reasonable amount of use since I measured them, so I'll be interested to see how much they've changed when I get the chance to measure them at the weekend...
Something that may affect your measurements (although probably not the sanity-check frequency) - does your meter measure true-RMS?
Cheers,
Mark 😉
richie00boy said:I've been trying to measure an AP100Z0 this evening. It's straight out of the box. I measured Fs at 96Hz.
I'm having problems with the Fl and Fh for calculating Q though -- the sanity check yields Fs of 90Hz. I'm using the Brian Steele method, but without any series resistor -- just putting my meter in series and reading off current. Should be the same thingThe meter is staying on the same range so it's resistance is constant, so that rules that out.
Must try and get my constant-current circuit sorted and see if that gives any better results.
I found that a brand-new driver needed running for a couple of minutes before FS would stabilise. Did you go back and re-check FS? It's possible it was just running in while you were making the measurements.
Two of my drivers have had a reasonable amount of use since I measured them, so I'll be interested to see how much they've changed when I get the chance to measure them at the weekend...
Something that may affect your measurements (although probably not the sanity-check frequency) - does your meter measure true-RMS?
Cheers,
Mark 😉
I went back and manually checked Fs after getting the 'wrong' sanity check result. It was within 0.25Hz of my original reading. I was only driving at 200mV, so no chances of significant cone movement to cause running-in. If your driver is running in whilst you are testing it then you are driving it far too hard! I also did the entire test again to double check. Same results 🙁
The meter I am using is a top of the range Fluke that I have just skinted myself out on. It measures true RMS and frequency at the same time. I bought the meter as I was fed up with faffing about with leads, blurry scope screens and laborious reading interpretation. So I'm a little cross that it's not going right!
The meter I am using is a top of the range Fluke that I have just skinted myself out on. It measures true RMS and frequency at the same time. I bought the meter as I was fed up with faffing about with leads, blurry scope screens and laborious reading interpretation. So I'm a little cross that it's not going right!
richie00boy said:
That's true, but these drivers do seem to need a little run-in from brand new. The new driver I was talking about had an initial FS in the 80's, and I knew that the others that I had tested were in the 60's. These had all had some (not much) use. So, I ran it for a few minutes at around 15Hz, letting the cone move a few mm's each way. I left it for a few minutes before measuring FS again (in case there was any voicecoil heating). FS now measured 66.9Hz, and the sanity check gave 66.58
I was using 1.41V RMS, and a 7.5 ohm series resistance for the measurements... Your sanity-check results suggests a problem with the experiment rather than the driver. I guess your signal source is flat? I also guess your Fluke has a flat frequency response at these frequencies? These two are easy enough to check. I'm not sure what else is there to go wrong... One thing - you're measuring current directly - I wonder if it's worth trying a series resistor? That way, you can type the numbers directly into the spreadsheet...
I can understand your frustration. I noted that others have run these things in for many hours at mechanical limits (not xmax!) - I haven't done that, but already I have results that are pretty close to Audax's numbers. I will be able to do more testing at the weekend - I'll also measure the unused pair. Maybe I've just been lucky with the pair I'm currently listening to 🙂
Sounds nice! What model did you go for? I've been promising myself a proper Fluke for 10 years now 😉
Cheers,
Mark 😉
I'm expecting Fs to be high and it's not a problem, the sanity check is. I'm want to do a before and after running-in, to see how much difference it makes. I'm wondering if just an hour or so will run it in enough.
I can't see how it can affect the results doing it on pure current measurement, but I'm going to try a series resistor of 10 ohms and see what results I get then.
I'm confident in the source as that's a decent signal generator. The meter is also flat (within 1.5%) from 0.5Hz to 100kHz, IIRC. I got a Fluke 187 with cal certificate. Basically my mate bought it when he got a new job. Then about a month later his contract ran out and there was no work for him, so he was in need of cash. So I got a huge bargain 😀
I can't see how it can affect the results doing it on pure current measurement, but I'm going to try a series resistor of 10 ohms and see what results I get then.
I'm confident in the source as that's a decent signal generator. The meter is also flat (within 1.5%) from 0.5Hz to 100kHz, IIRC. I got a Fluke 187 with cal certificate. Basically my mate bought it when he got a new job. Then about a month later his contract ran out and there was no work for him, so he was in need of cash. So I got a huge bargain 😀
Well mine are going to be probably a while yet. Althought the cabinets are pretty much (sort of others need choppin up) sorted. Im replacing the fronts of all my front end (amps preamp DAC etc) so they all match and then buliding and equipment rack. Realistically this shouldnt take too long, but things always take longer then you think!
Yeah I will be a while yet, too. I also have some of the AP210Z0 to make a budget Orion OB, and a major sub project to tackle.
I'm also trying to source a pair of TM025F1 to match up with the AP100Z0 as Maplin did get a new lot in then promptly removed them from sale/sold out.
I'm also trying to source a pair of TM025F1 to match up with the AP100Z0 as Maplin did get a new lot in then promptly removed them from sale/sold out.
i've been doing some testing lately, go with the two34xo, its in a different class! there are less than 20 left too!
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Budget Orion
Richie,
would that budget Orion be passive/active/bi-amped whatever? Last year I started a thread on using these Audax 8" for OB (specifically the M0 with its high Q) but was warned they would need a lot of EQ.
Mark,
is that a Wilmslow HSM there?
Ian
Richie,
would that budget Orion be passive/active/bi-amped whatever? Last year I started a thread on using these Audax 8" for OB (specifically the M0 with its high Q) but was warned they would need a lot of EQ.
Mark,
is that a Wilmslow HSM there?
Ian
Hi everyone,
I've now used my first pair of AP100Z0s 😎
A friend got some old Goodmans' from about 1960 from his Dad. They are 3-way - 1", 4", 15" and have a nice bottom end (as they would). One of the mids was a bit messed up and was distorting somewhat. The sound could be a bit ragged 😉
So I brought round the Audaxs, and compared sensitivity and DCR, and they were a close match, amazingly enough. So we just plopped them in, and changed the 3 caps per speaker from (ancient) electrolytics to old film caps I'd Ebayed.
The speakers sound EXCELLENT now, I'm pleased to report, and altho there isn't much actually coming from the Audax (maybe not as sensitive as is should be) the balance is pretty good. The bass drivers are run full range. Mid and tweet are 2nd order.
Being lazy, we didn't bother to seal the back of the Audax/mid, so it takes the pressure from the old 15" beasties. They seem to enjoy it though 😉
These speakers are driven by an amp I Ebayed for £7 - a battered Technics chip amp. (it was sold as not working so well, basically because the pots needed a good spraying 🙂)
This is now a fantastic system to accompany pool playing in his basement 😀
I've now used my first pair of AP100Z0s 😎
A friend got some old Goodmans' from about 1960 from his Dad. They are 3-way - 1", 4", 15" and have a nice bottom end (as they would). One of the mids was a bit messed up and was distorting somewhat. The sound could be a bit ragged 😉
So I brought round the Audaxs, and compared sensitivity and DCR, and they were a close match, amazingly enough. So we just plopped them in, and changed the 3 caps per speaker from (ancient) electrolytics to old film caps I'd Ebayed.
The speakers sound EXCELLENT now, I'm pleased to report, and altho there isn't much actually coming from the Audax (maybe not as sensitive as is should be) the balance is pretty good. The bass drivers are run full range. Mid and tweet are 2nd order.
Being lazy, we didn't bother to seal the back of the Audax/mid, so it takes the pressure from the old 15" beasties. They seem to enjoy it though 😉
These speakers are driven by an amp I Ebayed for £7 - a battered Technics chip amp. (it was sold as not working so well, basically because the pots needed a good spraying 🙂)
This is now a fantastic system to accompany pool playing in his basement 😀
Mark,
Have you tried the TW025M0? I have heard good things about the TW025M1 which is the same thing but with ferrofluid. Wonder how they compare to the TW034X0.
Ian,
Thanks for the tip, I will search for your post. From the data sheet the AP210M0 looks much better for OB; with high Qts and more Xmax. They would have cost me £20 less as well. Less haste next time...
Have you tried the TW025M0? I have heard good things about the TW025M1 which is the same thing but with ferrofluid. Wonder how they compare to the TW034X0.
Ian,
Thanks for the tip, I will search for your post. From the data sheet the AP210M0 looks much better for OB; with high Qts and more Xmax. They would have cost me £20 less as well. Less haste next time...
richie00boy said:
No, the small one in the photo is a TM025F1, which is/was £12 at maplins, the point i was making is that the £15 TW034X0, is extreemly better VFM IMO.
I've started on the cabinets for my AP100Z0 and TM025F1 2-way.
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on the data sheet the AP100 is drawn as having a 7mm thick fixing ring, it's actually nearer 4mm, the 7mm includes the height of the rubber cone surround, nearly caught me out!
I had a bit of a delima really; if you surface mount the AP100 you can mount it slightly over the tweeter, bringing the acoustic centres closer together, they are also better time aligned like that. But in the end i listned to Zaph'sSurface mounting woofers and tweeters page and rebated it.
Thanks Zaph - Great crossover design
After so much discussion and ideas this thread seems to have gone dead, i expect everyone is building and testing eh?
Well i just wanted to say thanks to Zaph, I copied your crossover design for my pair of speakers, and well - WOW. Anyone using a simple cap or inductor really ought not to. The design that Zaph outlines on his website totally transformed the pair i had running a very simple crossover - these speakers are connected to an Arcam CD73 - Rega Brio amp and they sound just great, so much for less than £100 - Bargain.
Thanks for sharing your ideas and designs, As you cabn probably tell I am a one very happy chappy, my speakers are now the best i have (More complete sounding than my H571 and scan speak 9500) and am now considering doing the P17 design also on your website.
Has anyone else nearing completion on these?
Is anyone still interested in meeting to see how they all compare?
Mark
After so much discussion and ideas this thread seems to have gone dead, i expect everyone is building and testing eh?
Well i just wanted to say thanks to Zaph, I copied your crossover design for my pair of speakers, and well - WOW. Anyone using a simple cap or inductor really ought not to. The design that Zaph outlines on his website totally transformed the pair i had running a very simple crossover - these speakers are connected to an Arcam CD73 - Rega Brio amp and they sound just great, so much for less than £100 - Bargain.
Thanks for sharing your ideas and designs, As you cabn probably tell I am a one very happy chappy, my speakers are now the best i have (More complete sounding than my H571 and scan speak 9500) and am now considering doing the P17 design also on your website.
Has anyone else nearing completion on these?
Is anyone still interested in meeting to see how they all compare?
Mark
Re: Thanks Zaph - Great crossover design
Yup - I finished mine and posted details on my site a few weeks ago. Used John's crossover, and I agree completely - it's great. I've emailed him privately to express gratitude, and credited him extensibly on the site. There's also lot's of stuff on the site about the sound quality, so I won't repeat myself here, apart from saying that my initial impressions were that I might prefer a bit less top end. I'm waiting until my reference ATC's are out of storage before making my mind up, but I found that increasing C3 to 2u tamed it sufficiently, without seeming to affect midrange integration.
More details at http://www.mhennessy.f9.co.uk/audax/monitors.htm
Cheers,
Mark 😉
D1GGY said:
Yup - I finished mine and posted details on my site a few weeks ago. Used John's crossover, and I agree completely - it's great. I've emailed him privately to express gratitude, and credited him extensibly on the site. There's also lot's of stuff on the site about the sound quality, so I won't repeat myself here, apart from saying that my initial impressions were that I might prefer a bit less top end. I'm waiting until my reference ATC's are out of storage before making my mind up, but I found that increasing C3 to 2u tamed it sufficiently, without seeming to affect midrange integration.
More details at http://www.mhennessy.f9.co.uk/audax/monitors.htm
An externally hosted image should be here but it was not working when we last tested it.
Cheers,
Mark 😉
Mark they look great.
Anyone got any idea of some alternative tweeters that could be used with Johns design.
I didnt get any of the audax ones before they dissapeared, but I have a lot of AP100Z0 !!
Anyone got any idea of some alternative tweeters that could be used with Johns design.
I didnt get any of the audax ones before they dissapeared, but I have a lot of AP100Z0 !!
Im not sure when I will have mine done. I have changed the design that I am going to do however. A small ported two way like zaph originally did but with a vifa tweeter.
Im currently veneering the boxes to a current project of scan95 and peerless HDS 6.5" with phase plug.
Once I have veneered the boxes I will probably start on the Audax minis, or maybe after I have completely finished the others, I will have to wait and see.
Mark those look great 🙂 you did a very nice job with the finish.
Im currently veneering the boxes to a current project of scan95 and peerless HDS 6.5" with phase plug.
Once I have veneered the boxes I will probably start on the Audax minis, or maybe after I have completely finished the others, I will have to wait and see.
Mark those look great 🙂 you did a very nice job with the finish.
I am tied up with a subwoofer project at the moment. I have a design almost finalised in my head for these and am gathering parts together.
If any people are considering going active or into Gainclones, check out my thread in Trading Post re getting cheap LM3886T and PSU caps.
If any people are considering going active or into Gainclones, check out my thread in Trading Post re getting cheap LM3886T and PSU caps.
wytco0 said:
Thanks! I'm listening to them now in the office at work, and they sound great.
Speak to John K, but I suspect not. The crossover is quite specific to the characteristics of that driver. Are you sure you can't find one from somewhere else? It's a crazy thought, but I recently noticed that Harbeth have released a new range of speakers http://www.harbeth-nrg.co.uk/ that appear to use the F1 - Alan Shaw is a nice chap - perhaps he'd be willing to sell you a couple?
Cheers,
Mark 😉
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