Designing a highbass front horn

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   Hi there, sorry if I don't post in the correct location.
I'd like to design a horn to play in the 90Hz-400Hz band (maybe a bit higher if possible). This speaker would meet a tapped horn TPAM10HTL at 90Hz.  This is for home usage so I don't need a lot of power. Of course a vented enclosure would do the job easily but I like challenges ;-)
I played with a 8" driver (B&C 8PE21) in hornsrep and got this result : 
I tried to keep the compression ratio low (3:1 here). 3dB bandpass is [92,510], not bad. I have a few questions :
- Do you see any evident design mistakes ?
- the mouth of the horn is 30cmx30cm. I find it rather low when I compare to equivalent horns. Is is because I used a 8" driver ?
- I dont know how to interpret the phase response and the group delay. What do you think ?
- Is it useful to look at the impulse response ? What should I aim for ?
- If the design is ok, I'd like to try to fold it to reduce the size of the box. Do you think it's possible ?

Thank you !
Alban

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albanyaka51 Members Profile Send Private Message Find Members Posts Add to Buddy List New Member Joined: 26 September 2025 Status: Offline Points: 3	Post Options Post Reply Quote albanyaka51 Report Post Thanks(0) Quote Reply Topic: Designing a highbass front horn Posted: 26 September 2025 at 8:48am
	Hi there, sorry if I don't post in the correct location. I'd like to design a horn to play in the 90Hz-400Hz band (maybe a bit higher if possible). This speaker would meet a tapped horn TPAM10HTL at 90Hz. This is for home usage so I don't need a lot of power. Of course a vented enclosure would do the job easily but I like challenges ;-) I played with a 8" driver (B&C 8PE21) in hornsrep and got this result : I tried to keep the compression ratio low (3:1 here). 3dB bandpass is [92,510], not bad. I have a few questions : - Do you see any evident design mistakes ? - the mouth of the horn is 30cmx30cm. I find it rather low when I compare to equivalent horns. Is is because I used a 8" driver ? - I dont know how to interpret the phase response and the group delay. What do you think ? - Is it useful to look at the impulse response ? What should I aim for ? - If the design is ok, I'd like to try to fold it to reduce the size of the box. Do you think it's possible ? Thank you ! Alban

snowflake Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 29 December 2004 Location: Bristol Status: Offline Points: 3443	Post Options Post Reply Quote snowflake Report Post Thanks(0) Quote Reply Posted: 26 September 2025 at 9:23am
	unless you can get your speaker right into the corner of a room it is unlikely to have 0.5pi loading.

albanyaka51 Members Profile Send Private Message Find Members Posts Add to Buddy List New Member Joined: 26 September 2025 Status: Offline Points: 3	Post Options Post Reply Quote albanyaka51 Report Post Thanks(0) Quote Reply Posted: 26 September 2025 at 9:34am
	Good point, I didn't pay much attention to that as I thought going from 1Pi to 0.5Pi would only offset the power response 3dB up. Actually it lowers the response around 100Hz.

GEB Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 13 November 2009 Location: East Midlands Status: Offline Points: 2052	Post Options Post Reply Quote GEB Report Post Thanks(0) Quote Reply Posted: 26 September 2025 at 9:39am
	I'm no expert but folding will be a bad idea over 200 Hz. From what I've read a straight horn would be needed if going up that high in the frequency range.