Right now the new NAD with Purifi Eigentakt modules.What amps are you using?
Right now the new NAD with Purifi Eigentakt modules.What amps are you using?
Have you heard the OBs from Bert? It just surprises me that they will have less “whomp” as the FLH is both deeper/wider than 817, very similar to that of the 210/211 Altec cabinets.The open baffle ones, from Bert in Netherlands, had less midbass whoomp. I am not sure if it was because the OB was losing bass at the back, or because he uses these DIY SS amps. Also, don't think he was using altecs then.
The vents of your current Altec should give enough lower bass with 515 if done right and more than OB. If you desire lower you will need subs is my guess.
Just to confirm, when you say lower bass are you referring to below 30 Hz, or are you just in general referring to the feeling of weight? The 817 cabinet you have should have very good weight
Have you heard the OBs from Bert? It just surprises me that they will have less “whomp” as the FLH is both deeper/wider than 817, very similar to that of the 210/211 Altec cabinets.
no I have no plans below 30 hz, I am a music lover…. 35-40 will do just nicely!
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Have you heard the OBs from Bert? It just surprises me that they will have less “whomp” as the FLH is both deeper/wider than 817, very similar to that of the 210/211 Altec cabinets.
no I have no plans below 30 hz, I am a music lover…. 35-40 will do just nicely!
View attachment 90863
Ok! There you are… This room looks very “crowded“ and I guess the Bert‘s OB in the pictures has a less than ideal working conditions? my room(s) are way bigger.
That's me.
Like I said I don't know if less whoomp was due to baffle, drivers, or the amp. I wish he used SETs
In your case, I would first suggest trying with SETs. The Altec drivers have high damping and require an amp with high output impedance and less grip. If, as per conventional thinking you add an amp with higher grip or low output impedance for more bass, it does the opposite... Causes bass roll off. So you need to try low output sets. I don't know how the NAD is.
Ok! There you are… This room looks very “crowded“ and I guess the Bert‘s OB in the pictures has a less than ideal working conditions? my room(s) are way bigger.
I am not into SETs at the moment(been there done that) and as I use my system more than 8-10 hours a day Class A with the energy prices at the moment is not that attractive. I must admit that I have become somewhat lazy so all recourses and effort are being put into the speakers and that’s it.
As I am considering the OB in the picture your feedback is very much appreciated. Should I go or should I stay.
I fully respect and accept your point that SETs are the ideal amp for 515s. I have tried several amps with my system and many SS has a tendency to “over-grip“ and kill the bass.It is not about "being in sets". You are almost certainly losing bass because of your amp pairing.
Forums make people think "sets" is a thing. It is simply the right choice of amps for certain horns (or rather, certain drivers used in horns), and a bad choice for many other type of speakers. For altecs you will require a SETs based, or if push pull it will still have to be low grip high output impedance
I fully respect and accept your point that SETs are the ideal amp for 515s. I have tried several amps with my system and many SS has a tendency to “over-grip“ and kill the bass.
I am still kind of interested in trying OB so your opinion is very much appreciated.
Yes we did indeed and it was a great inspiration! We briefly touched into the possibility of adding wings! I have done that but they did not provide the wanted results and at the same time upset my wife to a new level of…. I made these wings(on both sides) but in the end only the dog was impressed!Klaus you heard my FLHs recently
did we discuss adding wings to the 817s?
As great as the Altec woofers are, but in light of Ked's comments, maybe Acoustic Elegance OB woofers?
Devor 40 ? ( Leif knows these )
Yes! And i have absolutely no sentimental feelings torwards the NAD amps, the Altec 515s is another level of “audio love“ (in lack of a better word) .Why change woofers when he can change amps?
I guess Bert uses BD15s......his own version.....
heard the smaller version of this baffel with Oris 270 and BMS 4592ND at Peter Stordiau´s place/Phasure dac and was not impressed to put it mild...
Output impedance is not something I've thought much about - what do you consider high enough to be a good match for the Altecs?
That's me.
Like I said I don't know if less whoomp was due to baffle, drivers, or the amp. I wish he used SETs
In your case, I would first suggest trying with SETs. The Altec drivers have high damping and require an amp with high output impedance and less grip. If, as per conventional thinking you add an amp with higher grip or low output impedance for more bass, it does the opposite... Causes bass roll off. So you need to try low output sets. I don't know how the NAD is.