Hey Now.
I am building a box for a buddy of mine who is rebuilding a ditton 44. He is using the Seas 19TFF1/H0737 tweeter and I was wondering if it needed its own enclosure or not. If it does need its own enclosure is is there a back cup i can use for it?
Thank you so much in advance.
I am building a box for a buddy of mine who is rebuilding a ditton 44. He is using the Seas 19TFF1/H0737 tweeter and I was wondering if it needed its own enclosure or not. If it does need its own enclosure is is there a back cup i can use for it?
Thank you so much in advance.
That tweeter appears to have a sealed back, so no it doesn't need a separate enclosure -
The Madisound Speaker Store - Seas19TFF1 Soft Dome Tweeter
However, the Celestion Ditton 44 appears to be a 3-way with a true Mid-Range Driver, if the Mid-Range is open back, then it might benefit from being placed in a small chamber of its own.
Steve/bluewizard
The Madisound Speaker Store - Seas19TFF1 Soft Dome Tweeter
However, the Celestion Ditton 44 appears to be a 3-way with a true Mid-Range Driver, if the Mid-Range is open back, then it might benefit from being placed in a small chamber of its own.
Steve/bluewizard
The Ditton 44 uses variously a cardboard tube or a wooden box on the midrange, but as mentioned that shouldn't affect the SEAS 19 TFF, which IS sealed.
Happen to have some lying about awaiting renovation myself:
😀
Happen to have some lying about awaiting renovation myself:
An externally hosted image should be here but it was not working when we last tested it.
😀
Do you happen to know the ft3 or liters of that enclosure for the bass woofer? I came up with 1.86 ft3 or 52 liters. I don't know if that that is accurate though because I never saw the inside of those baffles.
I thought about using pvc with rope caulk around it for the midrange enclosure...not sure though if thats a good idea. I am worried about vibration,
I've got some rather disorganised notes that gave 3L for the midrange and 45L for the bass with a considerable amount of acoustic foam to make that effectively bigger.
The crossover schematic is freely available, but note that changing the NP electrolytics on the bass filter for polys will make it peaky unless you add 1 ohm damping resistors. The rest can be upgraded at will IMO. 🙂
Always good to add a cardboard gasket or something to the midrange.
The crossover schematic is freely available, but note that changing the NP electrolytics on the bass filter for polys will make it peaky unless you add 1 ohm damping resistors. The rest can be upgraded at will IMO. 🙂
Always good to add a cardboard gasket or something to the midrange.
Having done this, system7, and having considerable experience experimenting with 44s over the years, I must say, do not imagine that you can simply exchange the electros for polyprops and be done with it.
I agree they need replacing ideally, but a few strategically placed resistors will keep them from sounding absolutely horrible, in the opinion of just about everybody that has loved these speakers and simply bought fancy new polypropylene caps of the same values as those in there. The result is simply a horrible, imbalanced mess.
I will post a schematic of my now upgraded 44s soon, but I have only fully upgraded the mid and treble circuits, having replaced the bass caps with modern electrolytics, which seem to work very well. Inductor upgrades come next, which will cost some too...
I agree they need replacing ideally, but a few strategically placed resistors will keep them from sounding absolutely horrible, in the opinion of just about everybody that has loved these speakers and simply bought fancy new polypropylene caps of the same values as those in there. The result is simply a horrible, imbalanced mess.
I will post a schematic of my now upgraded 44s soon, but I have only fully upgraded the mid and treble circuits, having replaced the bass caps with modern electrolytics, which seem to work very well. Inductor upgrades come next, which will cost some too...
Hi Lucas. I've never successfully modelled a NP capacitor Celestion (or any other three way) crossover without NEEDING to add resistors to polypropylenes.
It's just how it works. Curiously we are in AGREEMENT here. Adding shunt resistors is now what I do with three way modelling at the lower end. 🙂
I can't comment on midrange filters really, but don't they usually have resistors anyway. 😕
It's just how it works. Curiously we are in AGREEMENT here. Adding shunt resistors is now what I do with three way modelling at the lower end. 🙂
I can't comment on midrange filters really, but don't they usually have resistors anyway. 😕
So, hopefully you can just see that there is a 1R resistor in the treble circuit simply acting as an attenuator to the Seas 19mm mentioned by the OP. All caps are polypropylene, replacing fairly poor quality old film caps. the 15R original cap remains in its original place.
In the mid circuit a lot of experimentation was needed. Eventually I added 2R2 and 2R7 to replace the resistance of the original electros. Sound like a stupid idea? Well, it sure sounds better. If you want to make the circuit work and cross smoothly without such resistors, you'd better have a big box of parts and values, a lot of time, and some way of measuring a frequency sweep. This way retains the original character of the circuit, which is really excellent, and they are now wonderful speakers, as all agree.
In the bass circuit, I will change the inductors next to very low DCR ones P-core ones, and see how it goes...
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Because this is diyaudio, I'd assume you are willing to try a few things having redesigned a crossover with low loss poly capacitors. At the treble end, I have certainly encountered having to add a 2R/22R L-pad to the tweeter to get the SWEET CELESTION SOUND back.
IMO, polys can sound a bit harsh when used as substitutes. But that is for you to fiddle with. I have other fish to fry. I'm a very busy man. Give me a break. 😀
IMO, polys can sound a bit harsh when used as substitutes. But that is for you to fiddle with. I have other fish to fry. I'm a very busy man. Give me a break. 😀
It IS. That's why some of us love this game. I don't think much of the Celestion HF 2000 tweeters plastic diaphragm really. For sure it's well damped. But looking at my HF 2000 tweeters, I feel pretty sure they have the big and legendary AlNiCo magnets. That might explain a lot. 😀
I sold 2 pairs of HF2000 tweeters. Not the highlight of the 44s in my opinion. Seas 19TFF1 is the way to go! Really wonderful by comparison, in every way. £20 each, so not overly expensive either. Plus, the HF2000s go for a fortune on eBay!!!
I never worry about money really. If a tweeter is rubbish, it's worthless really. Except on eBay. 😕
Here's an interesting conundrum. Which of the below is likely to work better.
Now read Robin Marshall: A Modicum of Genius | Stereophile.com and reconsider. 🙂
Just late night entertainment really. Cheers. 😀
Here's an interesting conundrum. Which of the below is likely to work better.
Now read Robin Marshall: A Modicum of Genius | Stereophile.com and reconsider. 🙂
Just late night entertainment really. Cheers. 😀
Attachments
Interesting. I was thinking the Visaton might win before reading in all honesty.
I am a big 3 way speaker fan, hence the 44s, but if I were designing a pair of speakers today, or looking to make an established design, I would no doubt be looking at a 2 way, but unlike those horrid traditional 2 ways of a bass/mid and a tweeter, I'd be using a real 12" or even 15" bass driver and a quality mid/treble driver, such as a full range Mark Audio Alpair driver, with a high pass filter behind it.
Really, there is no need for a tweeter with one of those drivers. Their only flaw is the crappy bass (which some like/forgive, but not me).
Have you seen and heard this? Watch in Full HD for better sound quality (important!) My 7 year old assures me they're all there!!!!
http://www.youtube.com/watch?v=VxcbppCX6Rk
I am a big 3 way speaker fan, hence the 44s, but if I were designing a pair of speakers today, or looking to make an established design, I would no doubt be looking at a 2 way, but unlike those horrid traditional 2 ways of a bass/mid and a tweeter, I'd be using a real 12" or even 15" bass driver and a quality mid/treble driver, such as a full range Mark Audio Alpair driver, with a high pass filter behind it.
Really, there is no need for a tweeter with one of those drivers. Their only flaw is the crappy bass (which some like/forgive, but not me).
Have you seen and heard this? Watch in Full HD for better sound quality (important!) My 7 year old assures me they're all there!!!!
http://www.youtube.com/watch?v=VxcbppCX6Rk
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