As Zia suggested, it's also possible to fabricate signal level I/Cs from two single strands of CAT5 sourced #24 solid - or even finer gauge- but you can run into issues with strain relief, as most RCA connectors are predicated on large diameter & shielded cable.
You can also run into problems of low frequency hum or RF interference with longer lengths of unshielded cabling - twisting or braiding of multiple strands won't completely mitigate those issues.
That said, if you do elect to try for fun, be sure to use the cheapest RCS plugs you can find - they'll have the lowest amount of metal on contact surfaces, and usually light plastic covers.
You can also run into problems of low frequency hum or RF interference with longer lengths of unshielded cabling - twisting or braiding of multiple strands won't completely mitigate those issues.
That said, if you do elect to try for fun, be sure to use the cheapest RCS plugs you can find - they'll have the lowest amount of metal on contact surfaces, and usually light plastic covers.
Thanks Zman1 & Chrisb,
Was busy with finishing the exterior of my MK3 and super tweeter and hence the delay in try out of the CAT5 IC. The exterior has really taken a lot of effort and labor out of me. Instead of using Veneer I decided to clean my attic of Teak wood strips left over from my house construction. Had them cut and planed to about 7 mm thick strips. These were then stuck on the MDF cabinets, sanded, sealed, polished, sanded, sealed, pol... several times. The Tweeter is housed in a small teak block shaped quite nicely (also with the 5deg tilt) and also polished to a finish.
After this I have tried out the CAT6 (23 AWG) IC.. with a pair of twisted pairs for each side. Have kept it short to avoid picking up noise. Sounds simply sublime - no disturbance.
Was busy with finishing the exterior of my MK3 and super tweeter and hence the delay in try out of the CAT5 IC. The exterior has really taken a lot of effort and labor out of me. Instead of using Veneer I decided to clean my attic of Teak wood strips left over from my house construction. Had them cut and planed to about 7 mm thick strips. These were then stuck on the MDF cabinets, sanded, sealed, polished, sanded, sealed, pol... several times. The Tweeter is housed in a small teak block shaped quite nicely (also with the 5deg tilt) and also polished to a finish.
After this I have tried out the CAT6 (23 AWG) IC.. with a pair of twisted pairs for each side. Have kept it short to avoid picking up noise. Sounds simply sublime - no disturbance.
Hello all,
I understand that Mark is ill with cancer does anyone know how he is at the moment?
I've had my FH3's now for about 7 years and still listen to them with amazement every time I buy a new CD.
I used to have a web site about my build and the gain clone that drives them and other web sites for the other pastimes I'm engaged in. I ditched the lot a few weeks ago and started to use Blogger, which can be made to look like a web site now, link below.
I hadn't visited the site for sometime and was amazed to see the thread about the Karlsonator and was very impressed with the MP3's people had posted. I even began to think about making a pair and then .... I came across an "FH3" made from foam board and its associated MP3. Well just hear the difference! So as you do I went off to listen to mine and was bathed in glorious sound. I'm still using Marks CHP-70's the 4 Ohm ones ... superb!
Cheers
[edit] If anyone in the UK who lives not too far from M1Ju29 would like to have a listen then please contact me, I would be delighted to let you have a go!
I understand that Mark is ill with cancer does anyone know how he is at the moment?
I've had my FH3's now for about 7 years and still listen to them with amazement every time I buy a new CD.
I used to have a web site about my build and the gain clone that drives them and other web sites for the other pastimes I'm engaged in. I ditched the lot a few weeks ago and started to use Blogger, which can be made to look like a web site now, link below.
I hadn't visited the site for sometime and was amazed to see the thread about the Karlsonator and was very impressed with the MP3's people had posted. I even began to think about making a pair and then .... I came across an "FH3" made from foam board and its associated MP3. Well just hear the difference! So as you do I went off to listen to mine and was bathed in glorious sound. I'm still using Marks CHP-70's the 4 Ohm ones ... superb!
Cheers
[edit] If anyone in the UK who lives not too far from M1Ju29 would like to have a listen then please contact me, I would be delighted to let you have a go!
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It seems like 18mm thickness is hard to get here in Sweden. It's typically 16, 19, or 22mm. I still have a pair of spare EL70 drivers and I just joined a local makerspace community that has a woodworking workshop that I can use on Wednesday evenings for free. I'm thinking the frugel-horns might be a fun project for the summer. Build them in mdf because of price, availability and more forgiving to work with and then try to actually get a nice finish on them.
Update, I have looked at my CAD file and i already have both 12 & 19.05mm plans drawn, so i will just need to output them as pdfs, and integrate with th planet. There is other tidying to do, that may take more than just housekeeping. Stay tuned.
Existing plans have 15, 16, and 18mm as well as 15 with 18mm baffles (the last what we have used for our flat-paks).
dave
Existing plans have 15, 16, and 18mm as well as 15 with 18mm baffles (the last what we have used for our flat-paks).
dave
Here is the updated planet. It has grown by 11 pages.
It is interesting that this design is now nearly 8 years since the 1st document release!!
I have estinmated that there ar elikely over 1,000 pairs (based on how many flat-paks we have sold), but there could be alot more.
http://www.frugal-horn.com/downloads/frugel-hornMk3-1v0-060518.pdf
dave
It is interesting that this design is now nearly 8 years since the 1st document release!!
I have estinmated that there ar elikely over 1,000 pairs (based on how many flat-paks we have sold), but there could be alot more.
http://www.frugal-horn.com/downloads/frugel-hornMk3-1v0-060518.pdf
dave
Dave,
Thanks for your continued efforts in making the FH Mk3 plans more comprehensive and detailed. The diyAudio community will benefit from this.
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Hello Rullknufs,
I made my pair from MDF, link to my build blog below, before I made them I went and listened to a pair made from Plywood. After I'd got mine working I was entranced by the sound, still am. Never felt the want of making any others, I've never felt the need.
Even ones from cardboard, see above, sound great.
Cheers
Nice job.
Is it really ~8 years since we developed this wee beastie? That's gone quickly.
I'd make a conservative estimate at double that.
Hello everyone. I've wanted to build a pair of speakers for a long while and finally I feel like I have the time and money. I have ordered and received a pair of Alpair 7A generation 3's.
I have a few questions:
1. Is the curve on the speaker required for acoustic reasons? As I do not have all the tools in the world, the curve might pose a slight problem for me build wise. So I might skip out on the curve - I will have to see later on.
2. I feel like using MDF might be easier to cut with tools I have. Will there be a huge difference in sound quality? Which build material do you think would be best for sound quality - A 15mm 7-layer plywood or 16/18mm MDF board? ( Money is not an issue )
3. I saw kit for the frugal horn using 18mm MDF (I believe), and they only used glue to connect the major parts. Is it enough to only use glue to fit the parts together? Does it matter if it's MDF or plywood in this case?
Best regards,
Fredrik
I have a few questions:
1. Is the curve on the speaker required for acoustic reasons? As I do not have all the tools in the world, the curve might pose a slight problem for me build wise. So I might skip out on the curve - I will have to see later on
.2. I feel like using MDF might be easier to cut with tools I have. Will there be a huge difference in sound quality? Which build material do you think would be best for sound quality - A 15mm 7-layer plywood or 16/18mm MDF board? ( Money is not an issue
)3. I saw kit for the frugal horn using 18mm MDF (I believe), and they only used glue to connect the major parts. Is it enough to only use glue to fit the parts together? Does it matter if it's MDF or plywood in this case?
Best regards,
Fredrik
Fredrik,
The curve has acoustic affect. Ron Clarke did a lot of work on horn designs with his bespoke modeler (and real-world builds). The curve makes a rectangular mouth work more like the ideal circular mouth.
The 15mm ply will give the best result. I do not think MDF is a suitable material for building loudspeakers. 15mm 7 ply is not going to be of the best quality plywood, Baltic Birch will have 11 plies, the Murphy Ply we have been using has 2 additional Maple veneer plies added to that.
That said numbers of FH3s have been built with MDF and the owners are happy. On the other hand others have started with MDF horns and then rebuilt with quality plywood and report beening a bit stunned at the improvement.
For the A7.3 you have ordered 15mm will be a bit sketchy for the baffles once the rebate has been added.
None of the MDF kits are approved and may not have the appropriate King Model licence to be legal.
Glue is sufficient for a loudspeaker if used properly. Use yellow wood glue. White is not quite as good.
dave
The curve has acoustic affect. Ron Clarke did a lot of work on horn designs with his bespoke modeler (and real-world builds). The curve makes a rectangular mouth work more like the ideal circular mouth.
The 15mm ply will give the best result. I do not think MDF is a suitable material for building loudspeakers. 15mm 7 ply is not going to be of the best quality plywood, Baltic Birch will have 11 plies, the Murphy Ply we have been using has 2 additional Maple veneer plies added to that.
That said numbers of FH3s have been built with MDF and the owners are happy. On the other hand others have started with MDF horns and then rebuilt with quality plywood and report beening a bit stunned at the improvement.
For the A7.3 you have ordered 15mm will be a bit sketchy for the baffles once the rebate has been added.
None of the MDF kits are approved and may not have the appropriate King Model licence to be legal.
Glue is sufficient for a loudspeaker if used properly. Use yellow wood glue. White is not quite as good.
dave
Thanks for answering Dave!
Alright, I will try to keep the curve.
I have been looking for baltic birch plywood at the standard "home depot" equivalents here in Sweden, but haven't found the birch in any size larger than around 8mm so far. The 15mm I mentioned was "construction plywood", which I too understand is not very good
. I will try to find a shop which is more specialised in plywood.Sorry, I am still very much a beginner so I don't really know the loudspeaker terms that well. What would be the problem with the 15mm plywood regarding baffles and the rebate. (And what is a rebate?)
Since it is not the best, what plywood size would be optimal or better for the Alpair 7.3?
Many thanks,
Fredrik
I have heard the same from other Swedes… something i find a bit surprising since some of the world’s best plywood is made next door in Finland, and the Baltic states.
We have used 15mm for all but the baffles (18mm) in all of our FH3 flatpaks. One could avoid buying an extra sheet by building them with 15mm and using a vestigial supraBaffle made from something like an Ikea Bamboo cutting board (or other chunk of solid).
There is the driver cutour and then the part of the baffle around the hole removed to allow for the bezel to be flush with the baffle.
dave
I've googled some more and there seems to be a few sites which sell a lot of different types of plywood. They are just not regular stores so I guess I will have to do a custom order.
Okay, I will try to use the 18mm for the baffle part as well.
Took me a while to decipher this since I haven't understood all the diy language, but I think I got it. I understand that the bezel is wanted/required on the inside. However, the driver cutout on the outside, is this required other than the fact that it looks better when the driver isn't protuding out? I have a feeling it will be difficult to do this cutout with the tools I have at hand.
Also, I took a look at the mock assembly of the MK3 from your part of the forum which helped a lot
Thanks again,
Fredrik
Frederik, if you are close to Malmo and Copenhagen you might able to pop across for the wood. Don’t know what the Swedish wood prices are like but you can get good quality ply in e.g. XL here at quite reasonable prices. Alternatively you could ask your Home Depot if they can order some for you, as their suppliers might also stock some of the better stuff, the depot just doesn’t have it in shop because few consumers buy it.