Hello to all i have a Scott 299D which i restored and recapped with 716 orange drops and sounds fantastic. Right now i have a set of bose (I KNOW) inter audio 4000 speakers i got at a yard sale cheap in new condition . They sound ok with Lots of bass (10 inch woofers) but i cant find any info on them . Thinking of upgrading speakers what would be a good set that wont break the bank . Or could i use the bose boxes and replace the woofers and tweeters. any info appreciated.
AFAIK, these Bose Interaudio 4000 speakers are some sort of variation on the 10" bass plus 2" cone tweeter idea. It's one of those combinations that work well enough. Maybe some issue with foam rot on the surrounds of the bass after all these years. You could fix that.
How it works, is a 10" paper bass has a natural rolloff at about 2.5kHz. So you then cross it to a big tweeter that is comfortable at this frequency. Doesn't usually need a very complex crossover. But, TBH, the tweeter is always the stressed component. Cone tweeters have a pleasant sound, but not great dispersion at the top end.
But actually this is an ideal speaker for valve amps, which work best with a flattish impedance. TBH, they also work best with closed box rather than reflex. Just an easier load really. Stuffing the port with a sock to get nearer closed box could be a thing to try.
A variation on the theme with a bass that has the bass coil sort of built in:
SEAS A26 Kit
Here's how to get a REALLY good flat impedance:
Rogers Loudspeakers › LS5/9
It's based on the idea of equalising the bass unit's voicecoil inductance, and applying a very passive sort of bafflestep:
mh-audio.nl - Home
Another idea is to build a 3 way using the 10" bass:
SEAS Kit 503
Few ideas below, including the satisfactory Wharfedale Melton II I used to own. It's usually positive polarity on simple crossovers, but can be negative polarity occasionally. I am willing to look into that if you firm your ideas up a bit. So welcome to the hobby. 😎
How it works, is a 10" paper bass has a natural rolloff at about 2.5kHz. So you then cross it to a big tweeter that is comfortable at this frequency. Doesn't usually need a very complex crossover. But, TBH, the tweeter is always the stressed component. Cone tweeters have a pleasant sound, but not great dispersion at the top end.
But actually this is an ideal speaker for valve amps, which work best with a flattish impedance. TBH, they also work best with closed box rather than reflex. Just an easier load really. Stuffing the port with a sock to get nearer closed box could be a thing to try.
A variation on the theme with a bass that has the bass coil sort of built in:
SEAS A26 Kit
Here's how to get a REALLY good flat impedance:
Rogers Loudspeakers › LS5/9
It's based on the idea of equalising the bass unit's voicecoil inductance, and applying a very passive sort of bafflestep:
mh-audio.nl - Home
Another idea is to build a 3 way using the 10" bass:
SEAS Kit 503
Few ideas below, including the satisfactory Wharfedale Melton II I used to own. It's usually positive polarity on simple crossovers, but can be negative polarity occasionally. I am willing to look into that if you firm your ideas up a bit. So welcome to the hobby. 😎
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Thanks for the info angi and system7 thanks for your input the speaker on the left is the speakers i have now could i replace the tweeters and crossover to make a change for the better ???? on these .
There's not so much to be gained, swapping parts. Unless the tweeter capacitor has failed, I would prefer to save funds for a 'younger' speaker with newer drivers.
If you can find them, the Snell E type are comfortable with older power amps. http://www.snell.no/the_archives_type_E.htm
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If you can find them, the Snell E type are comfortable with older power amps. http://www.snell.no/the_archives_type_E.htm
Sent from my Nexus 6 using Tapatalk
Yup, I think you may be able to improve your speaker. 🙂Thanks for the info angi and system7 thanks for your input the speaker on the left is the speakers i have now could i replace the tweeters and crossover to make a change for the better ???? on these .

I used to have a very good valve amplifier. The Radford STA-25. Fiddly sort of amplifier, TBH. A lot of bias adjustment to get it sounding right. But when you did get it right, it sounded superb. 😀
This was years ago, of course. I have a theory about speakers which work best with valves. They like flat impedance. Valves really don't have sufficient damping factor or feedback to drive reflex boxes too well. Better big closed box, IMO.
Let's look at a speaker that works well with valves:
DeVore Fidelity Orangutan O/96 loudspeaker | Stereophile.com
10" bass plus a tweeter that can dig deep and low. Easy to drive, apparently. You take your beating on HF dispersion. Never a strength of cone tweeters.

To revisit this idea in the modern era, as anji12305 suggests, here's a genius design by my old friend marco_gea: http://www.diyaudio.com/forums/multi-way/147632-classic-monitor-designs-25.html#post4428857

I said earlier that the weak component in the 10" bass idea is the 2" tweeter crossed low at about 2.5kHz. It struggles to keep up. So one idea is to double up the tweeters. Gives them an easier ride.
I'd align them vertically, which works better IMO. So, overall, keep the bass if it is OK. But work on the tweeters and crossover. And I have done a certain amount of Impedance Equalisation here. BTW, 10" bass benefits from a 2.5kHz notch, which I have done below. 2nd order and fourth order both work. Your choice.
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Thanks guys the snells look fantastic . System 7 these bose speakers have Deep bass with the 10 inch woofer and could benefit from more mid and high for sure since they are all i have for now i can mod them for sure . what tweeters do you recommend ??
My friend, the results you obtain depend entirely on your level of commitment and enthusiasm. Have you even examined the crossover? Unscrew the bass and look.
Here's a modern reincarnation of a classic 10" design:
BBC LS5/9 - Graham Audio - British manufacturers of high quality loudspeaker systems
The filter is a joy for a BBC enthusiast like myself:
Rogers Loudspeakers › LS5/9
It's based on this idea of passive bafflestep and impedance correction:
mh-audio.nl - Home

Here's a modern reincarnation of a classic 10" design:
BBC LS5/9 - Graham Audio - British manufacturers of high quality loudspeaker systems
The filter is a joy for a BBC enthusiast like myself:
Rogers Loudspeakers › LS5/9
It's based on this idea of passive bafflestep and impedance correction:
mh-audio.nl - Home
Probably there's a 3.9 uF capacitor in line with the 4 Ω tweeter.Have you even examined the crossover? Unscrew the bass and look.
😱
Thanks guys i took the woofer out and here is what was there not a whole lot a small resistor and capacitor with what appears to be a fuse . Thanks system7 great read on the speakers .



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I picked up a beautiful set of KLH model 6 speakers i recapped them and they sound fantastic with the scott
Keep your eyes out for some vintage Altecs, they seem to love tube amps. Very efficient, they play loud and clean with only a few watts.
BillWojo
BillWojo
Karlson with good quality coax would really be good. For small speakers, I bet KLH 6 or even 17 would be great.
I say go the Seas A 26 kit. Great design. Glad Seas revived it. The simpler the XO the better. There are many possibilities but for me that one stands out.
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