Full Range Speaker Photo Gallery

[smallangryboy]

Many thanks !

[CLS]

Recently I set up a small system with OB & 8in fullranger.



The baffle is 90cmW x 120cmH. The offset driver position is determined by the program "Edge". I haven't got any chance to do any measurement, but in the critical midrange, to my ears they are as smooth as predicted.

The baffle is standing on their simple feet:


I put some soft close cell foam under the feet to make the system more compliant to the floor. I found this actually reduce the vibration.


The drivers were bought from local audio shop named Colin Sound Lab. I cut their dust caps.

I thought of inserting phase plug onto the pole piece. I found a pair of electrolytic caps with perfect diameter. I glued a piece of sheet iron on one end of the cap. However it refused to stay in center of the pole piece, instead, it's induced to the side wall of the voice coil former. Hmmm, maybe I should try a ring instead of a hole circular area....

Anyway, with the dust cap cut off, the lower treble already cleared up a lot. Originally it's a little rough around 2.5k~3k region. Now it's a lot smoother.




Hehe, and the amp is also "OB"

I put 2* RC filters for "baffle step" compensation ahead of 6J5 pre and SE 6H30pi power stage, totally they attenuate 15dB to the mid-high. But it's still not enough, I did additional EQ in the foobar with another 4~5dB. With all these EQ, the balance is now very good, very "full range".

[planet10]

Originally posted by CLS
Recently I set up a small system with OB & 8in fullranger.

....I cut their dust caps.I thought of inserting phase plug onto the pole piece. I found a pair of electrolytic caps with perfect diameter. I glued a piece of sheet iron on one end of the cap. However it refused to stay in center of the pole piece, instead, it's induced to the side wall of the voice coil former. Hmmm, maybe I should try a ring instead of a hole circular area....

Nice baffles and a very interesting looking driver.

To keep the phase plugs from trying to tip over you need to use 2 or 3 spearate pieces of metal. With a single piece, one end of the metal is attracted to the pole piece and the other is repealed.

dave

[ghpicard]

Originally posted by planet10
With a single piece, one end of the metal is attracted to the pole piece and the other is repealed.

There is no way that a piece of metal (not a magnet) be repelled by a magnet. The metal piece only tries to align with the force-field lines.
Actually, what's happening is that the sheet is being attracted to the gap because the attraction to the front of the pole piece is not enough to keep it.
The solution is to add magnetic mass so as the attracting force is enough to counter the side-traction. As you say, Dave, to put several pieces of metal, like a gluing a couple of nuts, or screwing a couple of screws will do the trick.

Gastón

[planet10]

Originally posted by ghpicard
There is no way that a piece of metal (not a magnet) be repelled by a magnet. The metal piece only tries to align with the force-field lines.
Actually, what's happening is that the sheet is being attracted to the gap because the attraction to the front of the pole piece is not enough to keep it.

That makes more sense. My explaination was more a thot experiment based on having the same problem with one of my 1st phase plug experiments -- i used a washer glued to the flat bit of a pair of foam earplugs for a thimble tweeter phase plug.... i was always straigtening it out.



dave

[Geoff H]

I've used single screws on phase plugs with success. It helps if the screw is recessed into the plug by a few thou.

That pole piece seems to have a centre machined into it. Ideal if it has. A brad driven into the plug with the head left slightly proud, would centre the plug.

Geoff.

[CLS]

Thanks alot for all the tips on phase plug. I'll keep trying.

About the driver, here are the specs:

model name: Colin Sound Lab SP-20

1. 8¡¨Full range
2. W fabric surround
3. paper cone
4. paper whizzer
5. 25mm voice coil, paper former
6. coil winding height 4 mm
7. gap width 1.8mm
8. magnetic density > 16000 gauss
9. Gap Height 5mm
10. Fs 45 Hz
11. nominal 8 ohm
12. frequncy range 45 ~ 20000 Hz
13. Qts 0.5
14. SPL 92 dB/w/1m
15. input power 15W max

This driver is no longer available. Now there's a SP-20MKII, with bigger magnet and voice coil and a warmer sound.


ps. The similarity of CSL (Colin Sound Lab) and my user name CLS is just a coincidence. CLS is the abbreviation of my Chinese name.

[skibell]

the sound is great ! now bass become very very better ( not stronger but more accurate )

Below pic is this boy.

Tks n brgds [/B][/QUOTE]

When building, you will notice that the more time you give to your speakers to burn-in, the more they'll develop a better sound. Plans please!

[skibell]

Originally posted by Semisentient
Hi guys,

Here is a quick pic of the Zigmahornets (with FE103E drivers) I recently put together.

Originally they were going to be light coloured so I put a maple veneer on them. We then decided to go with a mid tone so I applied a teak stain. Maple does not take stain well! Took much exta work to make them look good... The cabnets are made from 5/8" MDF. I routed a curve on the front two edges so I could wrap one piece of veneer around the front and sides. Plus it gives a nice smooth look...

Anyways this was the first time I had even done anything like this and enjoyed it very much. I discovered I really enjoy woodwork and have since bought a bunch of tools to help (mostly one tool - a Shopsmith).

I picked the Zigmahornet design since I figured it would look good with our new TV. They sound great as well, so now I am thinking of building new speakers for the theatre room! (Although a hushbox for my projector would be the best increase per dollar in sound performance )

Maybe some Voigt Pipes for the theatre... I have a 14' ceiling in there so I can make some huge ones!!!

Thanks, James

Those are very nice, and Shopsmith is a very good tool. Too bad they are not doing that well. Do you have more pics and details of the project?

[scottwilko]

here are my steel buschorns more pics coming soon