Playing with the resistors in the crossover
I spent a few hours testing different resistances at the tweeter-attenuation resistor and the treble-trap resistor on the Ultras. Time will spent. It turns out I like a brighter sound: 6.8 ohm at the attenuator and 10 ohms in the trap (although I'll revisit the 15 ohm resistor in the trap...it was close). Sort of like a poor man's version of tube swapping.
I haven't listened to these speakers in awhile. Very natural sounding. Great bass. Good with the vocals. Really enjoyable.
I spent a few hours testing different resistances at the tweeter-attenuation resistor and the treble-trap resistor on the Ultras. Time will spent. It turns out I like a brighter sound: 6.8 ohm at the attenuator and 10 ohms in the trap (although I'll revisit the 15 ohm resistor in the trap...it was close). Sort of like a poor man's version of tube swapping.
I haven't listened to these speakers in awhile. Very natural sounding. Great bass. Good with the vocals. Really enjoyable.
Tuning is important as the room and drivers can vary from place to place.
Barnes3: The Manzanita is an easy load to drive in terms of being stable, but does require a bit of power. Works well with most tube amps. One possibility to consider are the low to medium cost Chinese integrated tube amps out of Hong Kong. There are quite a few. Something that uses KT88, KT90, KT120 and or KT150 finals. Also look for a SRPP pre-amp design and amps that provide both ultra linear push pull and class A (triode) capabilities. The Manzanita really sings with Class A assuming 20 or more watts per channel. 30 or more is better of course. I Use a Meixing DA at my house and at Audio shows. The Music Angel Class A tube Integrated Amplifier KT88 XD800MKIII is less than $500 USD plus shipping which should be about $100 US for you. Just guessing on the shipping cost based on what I paid a while back. I site the Music Angel just as a basic reference of what is available that I know works well. Good luck!
Yes you "can" use it of course. I'm just not sure why you'd want to. Unless you already own a pair. The crossover would need major adjustment because the 15PR400 will not have have anything near the response of the GRS on baffle. You'd have to tame the much hotter midrange and upper octaves to get it to blend well on OB.
Let's hear what John has to say, but I don't think it's woofer that's well suited to this speaker.
Let's hear what John has to say, but I don't think it's woofer that's well suited to this speaker.
Fatal 15PR400
The differences between the GRS and Fatal are VAST! Troels has it pretty well figured out in his OBL-15 design. Love his comments at the bottom of his OBL-15 information pages.
If one has the Fatal it obviously can be used in an OB configuration, just will have to be a ground up design to make it perform up to its capabilities. No easy task.
If I wanted to do a design with it, I would likely use an high efficiency pro 8" - 12" coax for the mid and high end. Just a thought. So many good (potential) ways around the barn. Hope the above makes sense.
The differences between the GRS and Fatal are VAST! Troels has it pretty well figured out in his OBL-15 design. Love his comments at the bottom of his OBL-15 information pages.
If one has the Fatal it obviously can be used in an OB configuration, just will have to be a ground up design to make it perform up to its capabilities. No easy task.
If I wanted to do a design with it, I would likely use an high efficiency pro 8" - 12" coax for the mid and high end. Just a thought. So many good (potential) ways around the barn. Hope the above makes sense.
Interesting that the Faital Pro woofer has low QTS and it still works in an OB although a complete redesign is necessary as mentioned...
BTW I have been looking for the Peerless TC9FD18-08 as the final piece to the manzanita but its been out of stock for awhile now at Parts Express and Madisound. Where else to look?
BTW I have been looking for the Peerless TC9FD18-08 as the final piece to the manzanita but its been out of stock for awhile now at Parts Express and Madisound. Where else to look?
I came across this as an alternative to the Peerless. SB Acoustics SB10PGC21-4 3" Full Range. Any suggestions? Thanks.
Link here: SB Acoustics SB10PGC21-4 3" Full Range
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Option-2 FaitalPRO 3FE22 3" Neodymium Professional Full-Range Woofer 8 Ohm
Option-3 Visaton B 80 3.3" Full-Range Driver 8 Ohm
Option-4 Visaton B 100 4" Full-Range Driver 6 Ohm
Link here: SB Acoustics SB10PGC21-4 3" Full Range
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Option-2 FaitalPRO 3FE22 3" Neodymium Professional Full-Range Woofer 8 Ohm
Option-3 Visaton B 80 3.3" Full-Range Driver 8 Ohm
Option-4 Visaton B 100 4" Full-Range Driver 6 Ohm
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One thing to remember about the OBL-15 is the large effective baffle size and that it sits on the floor. The effective F= is way down into the mid 60 Hz area. This means the crossover is only correcting to a flat response to about 30 Hz, or about an octave. This is why the system can get away with a low QTS driver. This large of baffle is starting to approach an Infinite Baffle profile. Troel's fun crossover wise had to do with flattening the F Peak which given the effective baffle dimensions around 150 Hz.
Yup. I briefly messed about with these on a narrowish open baffle with limited power and was underwhelmed. They need some encouragement via amps or inches.
Anyone think I could substitute the FaitalPRO 4FE35? Specs seems like they would be a good fit. I was thinking about trying that along with an attempt at an active xover. I understand that the ideal way is to use the passive, but assuming the 4FE35 could be used, I have all the components already so it would essentially be a no cost build.
One thing I was not able to find out is what the passive xover components are doing from a frequency perspective to find a starting point with the minidsp. I have a calibrated mic so I will do tweak as I go, but was wondering about a good starting point with the setup. Thanks