fe127e bipoles

[planet10]

Here is a sim of what is expected for 2 FE127 in a 20 litre sealed box -- top curve is using average of over 100 FE127s measured in-house, bottom curve is with the factory data

dave

 

[gmilitano]

Re: Re: Re: fe127e bipoles

By good bass i mean i was expecting very weak or a good lack of bass. Except i was pleasantly surprised to hear firm bass when sitting (drivers at ear level). I do plan on building a pair of 10" sealed subs to accompany them though, once i have built a stereo BPA-300 to run them.

Again with the room placement, at the moment they are in a less then ideal place. Behind them is a glass sliding door which i have hung a fairly thick blanket from the top to cover it.

Also what i was saying about one speaker being quieter then the other, i found it was the cable running to the speaker was causing this. After trying different sources and different amp combinations i swapped the cables over to discover the "quietness" transfered with it. So i think i will make some new cables up once i have finished my new Aleph.

My sims are close to what Dave has shown, -3db@100Hz. This is a much higer Q driver than the datasheet indicates. Bass measures a bit better in room. Bass that is present is very nice and these blend well with a sub. Bipole provides better off axis and better soundstage, but imaging is not as good as a monopole.

My measurements show a small hole at 2kHz and a large peak at 7-8kHz that can be/is annoying (granted these are inexpensive drivers). A notch or active eq works well in addressing this and allows you to tune them to your likings. I have also had success toeing them in and toeing out a super T. Plus there are a lot of mods said to address this.

Room changes can be done fairly quick and I found they can have a bigger impact than much more time consuming and expensive changes.

I finished mine with paint. Looks better than the MDF, but I could not find a way to make the seams disappear. So keep that in mind if that sort of detail will bother you. Perhaps a thick paint would hide the imperfections.

Cheers

 

[planet10]

Re: Re: Re: Re: fe127e bipoles

a large peak at 7-8kHz that can be/is annoying (granted these are inexpensive drivers). A notch or active eq works well in addressing this and allows you to tune them to your likings.

Treatment works better

dave

 

[Scribble]

Well after pulling them forward to 3ft and hanging a blanket on the wall behind me to stop an annoying reflection, they sounded much more like i thought they should. Lost some of the bass i was refering to before, but the gain was worth it.

Then i powered them from by newly running Aleph 30, Wow! is all i can say. Night and day differance from the other 2 amps i tried. They now sound more balanced from left to right and imaging has improved (i know that's not what these speakers are trying to achieve). The sound also seems much more... i dont know... full? deep? powerful?.

I've got about 50 hours of music playing on them now and they are definitely sounding more musical with time.

Here is a pic of the amp in all it's current dodgy glory. Need to get the the blokes at work to make up some panels for it, so i can case it. The other heatsink with the 5 bridges on it is my dodgy voltage dropper until i get some inductors in to pull down the rails a bit.


Thanks for all the help!

 

[gmilitano]

That is great Scribble. Do you happen to know what the output impedance is of that amp? You should also try wire the speakers in series and parallel to see which works best with that amp.

Cheers