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Markaudio Designers and builders of audiophile grade drivers

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Old 13th April 2011, 08:08 AM   #11
_henry_ is offline _henry_  Australia
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hi mark,

what kind of qty for the gb? i think it will be interesting for few groups.

1. fullrange on a box
2. fullrange in ob (higher sens, higher fs, less xmax)
3. fullrange for satellites

all with similar footprint of the great driver as before with slight mods.

cheers
henry
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Old 13th April 2011, 10:39 AM   #12
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Quote:
Originally Posted by _henry_ View Post
hi mark,
what kind of qty for the gb? i think it will be interesting for few groups.
1. fullrange on a box
2. fullrange in ob (higher sens, higher fs, less xmax)
3. fullrange for satellites
all with similar footprint of the great driver as before with slight mods.
cheers
henry
Hi Henry,
We have to make drivers in lots of 1000. We can some times make smaller quantities but I usually have to make most components in lots of 2000 units.

Any speciality drivers are therefore challenging to make for an affordable price.

Thats my point about making drivers with more performance features. In the case of rising response, there's various choices for Diyers to make its response flatter, but if the response is flat in the first place, it narrows to market to only those guys who like that style of driver.

Sadly, its going to take me some time to build resources to afford to specialise more. I'm glad of all help and support from Diyers. I don't have the resources to match the big players.

Cheers

Mark.

Last edited by markaudio; 13th April 2011 at 10:44 AM. Reason: additional
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Old 13th April 2011, 10:51 AM   #13
_henry_ is offline _henry_  Australia
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Hi mark,

would it be possible to narrow the difference into 1 part only of the driver? which i guess is the cone.

although i suspect the % of prod cost of the cones have a good share on total cogs.

i dont know if we are asking too much already :d

i do hope u come out with higher sens driver 93db up. which adequate for 15-30watts amps.

cheers
henry



cheers
henry
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Old 13th April 2011, 03:19 PM   #14
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Quote:
Originally Posted by _henry_ View Post
Hi mark,

1 - would it be possible to narrow the difference into 1 part only of the driver? which i guess is the cone.

2 - although i suspect the % of prod cost of the cones have a good share on total cogs.

3 - i dont know if we are asking too much already :d

4 - i do hope u come out with higher sens driver 93db up. which adequate for 15-30watts amps.

cheers
henry
Hi Henry,
We're heading off Bob's topic so we can always make another thread is the buy idea takes off.
Answering......
1 - I wish driver design and making were that simple. Sorry but the answer is no.
2 - The cones cost a fair amount. Good cones aren't cheap. Factor is all my tooling costs and don't tell the bank manager.
3 - Depends on how many people sign up.
4 - It would have to be a larger driver. Development cost V how many am I going to sell?

I can't remember but didn't you buy some Alp7's? If so, please help this thread with feedback on the Alp7.

Thanks
Mark.
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Old 13th April 2011, 04:16 PM   #15
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Hi Bob,
Nice looking build. Looking at the front baffle, how thick is the material? Did you manage to round-off or angle the inside of the driver cut-out? The thing that worries me a bit is the close proximity of the top of the internal baffle to the rear of the driver. I guess you've adding damping material to mitigate internal reflection.
Thanks. The cabinet is made of 12mm BB, the baffle and top being doubled. The inside of the driver cutout has a 1/2" roundover. The entire front pipe, the top and the back of the cabinet are lined with 5/8" acoustic fiberglass. I have a bit of polyester batting in the front pipe, but I think that the speaker is a bit over damped. When the cabinet was simply stuffed with polyester, there was a huge resonance near 900Hz that was almost as strong as the main resonance. I still have some quality play time with this.

Quote:
Re "ringing at the top"? You've surprised me with this comment. With just over 7000 units in use, I'd have received allot of flack by now, if I were so far-off with this driver's design. Extended decay at this high F range is part of the performance extension to near 30-kHz. Looking at your waterfall, the Alp7 is doing what's expected with its 70-mm cone.
OK. This is my first try at a small driver, so I have some learing to do. As long as you are happy with the waterfall, I'll work with it. DSP EQ is super simple.

Bob
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Old 13th April 2011, 05:18 PM   #16
_henry_ is offline _henry_  Australia
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hi bob,

glad u try out other fullranges than the fostexs.

nice TL, are u using minidsp?

cheers
henry
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Old 13th April 2011, 06:19 PM   #17
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Originally Posted by _henry_ View Post
hi bob,

glad u try out other fullranges than the fostexs.
Thenyou are not aware of my MLTL and BR for the Tang Band W8-1772?

Quote:
nice TL, are u using minidsp?

cheers
henry
Thanks and no, I am using a VST EQ within Foobar2000.Then on to an M-Audio DAC and the amp of the day.

Bob
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Old 13th April 2011, 10:18 PM   #18
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Quote:
Originally Posted by Bob Brines View Post
Thanks. The cabinet is made of 12mm BB, the baffle and top being doubled. The inside of the driver cutout has a 1/2" roundover. The entire front pipe, the top and the back of the cabinet are lined with 5/8" acoustic fiberglass. I have a bit of polyester batting in the front pipe, but I think that the speaker is a bit over damped. When the cabinet was simply stuffed with polyester, there was a huge resonance near 900Hz that was almost as strong as the main resonance. I still have some quality play time with this.

OK. This is my first try at a small driver, so I have some learing to do. As long as you are happy with the waterfall, I'll work with it. DSP EQ is super simple.

Bob
Hi Bob,
An interesting project with potential. It does look very nice with its veneer. I remember member Scott playing with the idea of a compact TL but I'm not sure if it was for the Alp6's.

1/2" round on 24-mm front baffle I think should be OK as you've rebated the driver. You've possibly observed, the Alp7 frame design is very open, allowing for a relatively large excursion for this size of driver. Near optimal box design and sufficient damping for this driver are significant factors to consider. So likely that some experimentation will be needed.

Here's a thought for you and partly explains why I developed the Multi-form cone technology. Allot of audio folks place their speaks parallel (see pic from member Skeeter) with the rear wall, TV, furniture etc (wife factor also) creates typical off-axis positions of 10 to 20 degrees. I realised (5 years ago) that a cone with progressive wide dispersion characteristics would be useful. It would likely emit a significant central stereo image and with a rising response, thus compensating for the off-set positioning for most set-ups. You might also want to experiment on cab positioning and see how you get on.

Where Eq DSP may help well is taming contemporary source music. The Alp7 with its top-end characteristic is more sensitive in this area so it needs to be fed with well recorded source material. From memory, both of us have lamented on this forum re this issue. While in Tokyo last November, guesting at the High-end Audio show, "screaming Tweet" syndrome was very much in evidence, to the point where some systems were to my ears un-listenable. Possibly 50% of the problem was down to source material.

One other thought, the 15 X 24 room is fairly large for a pair of 70-mm cones to fill. I'm delighted they are coping well but there maybe some risk of over-driving. Maybe not to the point where damage might happen but possibly a little over-extension. Should be OK on low to moderate/normal volumes but best to observer the drivers under these load conditions and experiment. Ideally, the cones should only move around 2 to 3-mm (one way) under shock and non rhythmic bass loads (eg. drum roll etc.). Looking at your TL box, it should be quite bass/mid efficient so might do quite well in the larger room setting.

Your feedback comes at the right time as I'm getting close to saying more about the next batch of Alp7.

Thanks
Mark
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Last edited by markaudio; 13th April 2011 at 10:36 PM. Reason: typo fix
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Old 13th April 2011, 10:58 PM   #19
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from what little I can see, those new dust caps look sexy!
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