Sonido fullrange driver thoughts?

frugal-phile™
Joined 2001
Paid Member
No you do not.

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http://wodendesign.com/maeshowe.html

Works very well with EL70 Qts = 0.55

Frugel-Horns are also a good example, the drivers that ar emarginal are low Q.

dave
 
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At the risk of causing offense (none being intended) ;) Dave is correct. A chambered back-loaded horn (and some chamberless, for related but slightly different reasons) is essentially just an extreme variation on the vented box principle. 'All' you're ultimately doing is loading the driver over the necessary low freqency BW -assuming its -3dB mass corner is low enough for GD not to become an obvious issue. Providing the motor has enough strength to overcome the air load, what a back horn ultimately wants is a driver suited to vented box loading. Low Q as a requirement for back-horns is something of a myth in & of itself, and a holdover from the days when watts were [extremely] expensive, and amplifer output impedances either variable or fixed and relatively high. Combine those and you end up with just that. Remove the amplifier or equivalent correction from the equation and things can start falling apart quite quickly.
 
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Please, I would like to clearly show how the quality factor affects the frequency response of vented box. This is the same Field Coil driver, only with a different quality factor.
And in the rear horn, this difference is not big.
 

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No necessary from this end, but I'm sure many here will wish to take you up on that, so many thanks indeed! :)

Agreed, for practical purposes, Fs, Vas and effective Qts' dominate the volume & tuning requirements for any given vented alignment, with Qts' having a disproportionately large effect relative to the others. With Fs, Vas held static & Qts' dropping, then assuming you're tracking the same mathematical alignment Vb will decrease and Fb raise in proportion, and visa versa for Qts' increasing, out to the practical 0.625 limit defined by Keele.
 
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Hi gents,

My DIY first try (poor-mans-build) with the lovely SFR175A. This cabinet was recommended by Janos from RealWorldAudio YT-Channel and initially for Fostex FF125WK. No speaker Terminals, Kimber cable direct soldered to driver.

Already have SFR-200A and SWR-300 in spare for next project.

This driver is awesome and this little, slot-ported cabinet is such fun to listen, also low frequencies are fine (sorry, no measures, listening Tests only and always people suprised how big soundstage and vocal precision is...). Of course most power I get with tube gear...

20231130_140304 - Kopie.jpg 20230710_142531.jpg 20230710_141919.jpg

I've to say, I really love those drivers and price/quality is at least for me unbeatable!!

Bst rgds,
Gerald
 
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Gerihifi,
Those are nice boxes for your Sonido SFR175A. I just finished building enclosures for my same drivers from plans I got from Scottmoose. I'm really enjoying the sound, very detailed, layered and throw a huge soundstage.

sfr175a.jpg
 
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Soundsmith,
Cabinet is a traditional duct vented standmount. 18mm baltic birch finished with cherry veneer. Baffle is blue stained walnut veneer.
There's front to back and side to side bracing, one above and another below the driver.
 
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I find the SFR 175 very detailed. Not having heard many FR speakers, can someone explain to me, in laymen terms, what is the FR shout that I've read about?
Last night I was listening to Peter Gabriel's debut solo album and he sound like he was far away and singing through a cone. I'm not very good at describing sound but his voice did not sound natural. Was it the recording? Was it the speaker?
 
one way to do it would be to visit a hifi shop with your Peter Gabriel solo album and listen to it on their rig. Another option would be to ask them if you can take a pair of speakers which are compatible with your electronics for an in home trial audition. Compare the two speakers against one another in your listening environment with your electronics.