Oktyabr, I can't speak to your equipment choices, since i haven't used most of it. I can make some comments on what I have found with my pair of Papa's SLOBs.
These are my opinions-
1. I noticed a large improvement when I changed from a Fostex Fe206EN to a Lii Audio Fast 8" FR driver. I think the FR driver choice makes up most of the sound you hear and I'd put an emphasis on finding one you like. I think the Fast 8 is a good starting point.
2. I tried the speakers with an SAE 4000 opamp based crossover. I recapped it and updated the opamps. I thought it sounded pretty good. Then I built Papa's 6-24 crossover with values for the SLOB. It was no contest and I haven't used the SAE since. I do think a good crossover with values for the SLOB makes a difference.
3. If you use the 6-24 make sure to turn the sound levels all the way up and decrease the FR or woofer to balance it to where you like it. You cannot use the stock 6-24 values. They need to be updated for the SLOBs.
3. I put my SLOBs on casters to make them easier to move and to raise the FR driver closer to ear height when sitting. I noticed this effect from my Zu speakers. I liked the Zu's but in comparison to the SLOBs they had no bass. Once the SLOBs moved in the Zu's moved out. You could also move the position of the FR drivers slightly higher on the baffle, although it won't look as balanced.
4. I use a pair of Hawthorne Augie 15's for the woofers. I think they are based on one of the Eminence woofers. I get a lot or a little bass depending on the amp a use with them. My opinion is that the amp matters more than the woofers, as long as they are good woofers. My best results are Aleph 2 monos (which is a bit of overkill). Class D is OK. I like them with an F1J for a lower powered amp. My least favorite with them is the ACA amps.
5. For the FR drivers my current favorite is the F2J. You won't need much power here and I like the sound and performance of Papa's current source amps. The VFET and F1J are good, too. ACA works well here. I'm going to guess any FW amp will sound great. i think it's important to have a great sounding amp here.
6. I'm thinking about adding a tweeter for a little more sparkle. Maybe something like the Parts Express ND16FA-6 with a 2.2uF Cap, that Papa is going to use on the upcoming speaker build camp. It's cheap (and out of stock) so why not?
7. Lastly, I'd make the front baffles removable. You will want to try different FR drivers and they all have different shapes. Modifying a baffle that is not removable is a chore. Make a couple pair of baffles when you're cutting the wood. I wish I did.
These are my opinions-
1. I noticed a large improvement when I changed from a Fostex Fe206EN to a Lii Audio Fast 8" FR driver. I think the FR driver choice makes up most of the sound you hear and I'd put an emphasis on finding one you like. I think the Fast 8 is a good starting point.
2. I tried the speakers with an SAE 4000 opamp based crossover. I recapped it and updated the opamps. I thought it sounded pretty good. Then I built Papa's 6-24 crossover with values for the SLOB. It was no contest and I haven't used the SAE since. I do think a good crossover with values for the SLOB makes a difference.
3. If you use the 6-24 make sure to turn the sound levels all the way up and decrease the FR or woofer to balance it to where you like it. You cannot use the stock 6-24 values. They need to be updated for the SLOBs.
3. I put my SLOBs on casters to make them easier to move and to raise the FR driver closer to ear height when sitting. I noticed this effect from my Zu speakers. I liked the Zu's but in comparison to the SLOBs they had no bass. Once the SLOBs moved in the Zu's moved out. You could also move the position of the FR drivers slightly higher on the baffle, although it won't look as balanced.
4. I use a pair of Hawthorne Augie 15's for the woofers. I think they are based on one of the Eminence woofers. I get a lot or a little bass depending on the amp a use with them. My opinion is that the amp matters more than the woofers, as long as they are good woofers. My best results are Aleph 2 monos (which is a bit of overkill). Class D is OK. I like them with an F1J for a lower powered amp. My least favorite with them is the ACA amps.
5. For the FR drivers my current favorite is the F2J. You won't need much power here and I like the sound and performance of Papa's current source amps. The VFET and F1J are good, too. ACA works well here. I'm going to guess any FW amp will sound great. i think it's important to have a great sounding amp here.
6. I'm thinking about adding a tweeter for a little more sparkle. Maybe something like the Parts Express ND16FA-6 with a 2.2uF Cap, that Papa is going to use on the upcoming speaker build camp. It's cheap (and out of stock) so why not?
7. Lastly, I'd make the front baffles removable. You will want to try different FR drivers and they all have different shapes. Modifying a baffle that is not removable is a chore. Make a couple pair of baffles when you're cutting the wood. I wish I did.
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Dayton-branded looks the same but declares a very low QTS...
Eminence starts @ around 200$ per pair (Beta 15). A cheap alternative (but with higher Fs) would be the Thomann Box 15:
The Eminence Definimax 4015ULF-8 used in Papa's single driver SLOB has a Qts of only 0.34 It's one of the reasons this build piqued my curiosity: being able to dabble with lower Qts woofers?
WG, did you mean ACN, not 6-24, right?
Merry Christmas
Yes, my mistake. I should have said I use an updated LXmini/ Analog Crossover network, not the 6-24 crossover.
I always get the two names mixed up.....
Merry Christmas!
I bought a pair of ebay from a seller in Brooklyn, NY, they were $500 a pair, last I saw he had two pairs left.
I'm having to choose an alternative to the Definimax units - the cost of getting a pair shipped from the US to the UK is way too much. The problem I have is that I'm not really sure what criteria I'm selecting on for the SLOB context. I think a decent XMax is important (to accomodate any required bottom-end lift) and efficiency clearly needs to be in the right ballpark. Nelson reported earlier in this thread that Qts isn't too critical.
I have a pair of Aurel Bryan FR8Dfe units for the full-rangers, they're 95dB/W/m, but if things work out I would love to eventually try some Cubes.
I'm hoping to start cutting wood in the New Year, once my arm has recovered from a nasty fall I had - now I know why slipways are called slipways!
I have a pair of Aurel Bryan FR8Dfe units for the full-rangers, they're 95dB/W/m, but if things work out I would love to eventually try some Cubes.
I'm hoping to start cutting wood in the New Year, once my arm has recovered from a nasty fall I had - now I know why slipways are called slipways!
Eminence still lists them on their website at US$254 each.
https://www.eminence.com/speakers/speaker-detail/?model=Definimax_4015ULF_8
Nelson boost the bass +6db ...maybe will put out small active jfet booster
the original ones definimax 4015LF qts 0,54
The LX mini crossover is identical to the SLOB crossover except for RC values
Personally I think anything with Qts of the .54 or lower will work fine. Probably
even the Eminence Alphas will do it, but I prefer having a real magnet....
nice Peppino
sure , no more qts .... single alpha is really bad is qts sky rockets more with excursionThe LX mini crossover is identical to the SLOB crossover except for RC values
Personally I think anything with Qts of the .54 or lower will work fine. Probably
even the Eminence Alphas will do it, but I prefer having a real magnet....
Looking good Peppennino. Have you settled on a bass driver yet?
I think I'm going for a pair of these as a reasonable approximation to the original Definimax 4015LF units - I think they have real magnets!
https://www.bcspeakers.com/en/products/lf-driver/15-0/8/15ps100-8
When I eventually get there, I will have removable baffles so I can experiment with the full-rangers; I have a pair of Aurel Bryan FR8DFe units available
I think I'm going for a pair of these as a reasonable approximation to the original Definimax 4015LF units - I think they have real magnets!
https://www.bcspeakers.com/en/products/lf-driver/15-0/8/15ps100-8
When I eventually get there, I will have removable baffles so I can experiment with the full-rangers; I have a pair of Aurel Bryan FR8DFe units available
How much does Vas really matter, on an open baffle? What range is ideal (for a 15" woofer)?
Clicking the link says I don't have permission. Are you sure you made it shareable?