Frugel-Horn Mk3 Builds & Build Questions

Thanks jemraid. Yes I got that blue tac idea from you earlier in these FH3 threads and I am definitely going to try it. A great idea!

Dave, sorry to be painfully stupid... If I understand you correctly I should put a second layer of felt on the inside panel behind the driver, the piece that folds from behind the driver around to the V section?
 
Hello Zia,

Thanks for the nice comment hope you and yours are OK too.

I didn't complete the HLM sadly my fault entirely, what I did do though was to make another gainclone to drive the CHP70's with a 12v supply and some large Caps from my failed HLM project. It sounds a lot fatter then the thin sound from my other gainclone, more akin to what I heard at Toppsy's house from his valve amp.

Must be nearly a year since I made the FH3's and I'm still gobsmacked by the sound. We had some builders doing some work and they didn't believe that there was only one small drive unit and were looking in the back for another one.

I must finish off that webpage with some more pics.

Hello VS you must have a lot of patience to look all through this thread :) I'm sure that will see you through to the best pair of speakers you've ever made.

And Eyup Dave bet you didn't think the design would go ballistic, it really is the best thing since sliced bread :)

Cheers - Jim
 
I must finish off that webpage with some more pics.

Hello VS you must have a lot of patience to look all through this thread :) I'm sure that will see you through to the best pair of speakers you've ever made.

Cheers - Jim
Yes you should update / finish that webpage :)

I actually didn't read through the complete thread.... I did an image search on google and came across it that way. I'm glad I did as I was planning on making some "special" wooden clamps (2x4 wood planks with threaded bar and nuts) to hold the loose panel on. That would have been :cr@p:
 
Hi Dave please help, I have attached some pics of my attempt to stuffing the FH3's. You mention carefull stuffing...does the stuffing in the V look OK (see pic1) or do I need to fluff it more. I found it quite difficult to not get those clumps of stuffing. Also, the felt I'm using is not quite as thick as 12mm, prob 8-10mm (see pic2), is this OK or should I put another layer over the existing?

BTW - I have 30g in the V and 20g in the throat as you see it. I also stuck valcro down the side panels of the throat (see pic3) to prevent the stuffing from falling to the bottom.

Thanks!
Where did you get the felt? IE what kind of store?
 
That choke in the output of the horn intrigued me. I had never seen that kind of thing before and at first I thought that we were looking at a mass loaded transmission line rather than a horn. I began pondering the use of the concept in FLHs and so I did a simulation in hornresp of a 30Hz FLH with smaller than ideal mouth area. I then added a choke to the mouth of the horn. Lo and behold the response flattened (mid range came down slightly and the low end droop was countered) with a slight increase in ripple throughout the passband.

I wonder if this would bear out in reality. If so it could be very useful in making smaller bass horns. I figured that a choke would destroy the efficiency but it doesn't really look that way, if of reasonable amount.

I will post sims later but just thought I would share.
 
The effect isn't huge and the evening of the average response above the first couple of octaves is mainly a lowering of troughs rather than the peaks but within the first octave and a half to two octaves some improvement does seem to be there.

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First listening impressions

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Last night I managed to put the FH3's "together" for the first time. One side panel of each was stuck on with sticky tac (see pics)

At first I was very impressed and had a smile on my face. Female vocals sounded very good, Diana Krall had new life in her CD's that I know very well. After some more listening to other source material such as Jack Johnson's Sleep through the Static I found that there was a brightness that was quite harsh and listening fatigue set in. Other genres like Jazz at the Pawnshop sounded good with the sax sounding very accurate and all instruments were easily distinguishable and well separated but overall I thought the FH3's were lacking warmth and body. The upper midrange is too dominant...I think.

So, I would like to know where to go from here with the stuffing arrangement. As I mentioned before I have 30g in the V and 20g in the mouth below the driver. I have another 20g to add to the 20g in the mouth but what can I expect to change or rather in which direction should I go? Any suggestions on improvements will be appreciated.
 
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