@Randy Bassinga I asked about the FFA002V2 and was told "With the aluminum plate, the total size is 116*256mm, and the height is 42mm inc, the plate'
It was time to listen to the FFA001V3 without it’s Input board, driven by a small buffer.
The buffer board is the one shown here https://www.diyaudio.com/community/threads/2x150w-amp-module-for-sale.388868/post-7254865
My impression of the combination is positive, like zoom77 described it here: https://www.diyaudio.com/community/threads/2x150w-amp-module-for-sale.388868/post-7254726.
George
The buffer board is the one shown here https://www.diyaudio.com/community/threads/2x150w-amp-module-for-sale.388868/post-7254865
My impression of the combination is positive, like zoom77 described it here: https://www.diyaudio.com/community/threads/2x150w-amp-module-for-sale.388868/post-7254726.
George
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Hi mkane
There are several offerings:
https://www.ebay.com/sch/i.html?_fr...T+Input+Cascoded+Buffer+Preamp+Board&_sacat=0
George
There are several offerings:
https://www.ebay.com/sch/i.html?_fr...T+Input+Cascoded+Buffer+Preamp+Board&_sacat=0
George
In the thread about @hifijim 's Compact, low cost, active 3-way speaker, there's a discussion of the HF variations of some class-D amps when presented with different speaker impedance loads. Specifically....
uriy-ch said:
In your amp designs, Eric, is the LPF covered by feedback?
Note: I have not perceived any HF variations with my FFA001V3 amps but even if the LPF is covered by feedback, no effect is likely because the tweeters are driven directly by the amp: They are all active systems, no passive components between amp and speaker to change the impedance of the driver. This would be good to know because these amps will be used with passive crossover speakers that do have much greater variations in the impedance curve.
uriy-ch said:
In your amp designs, Eric, is the LPF covered by feedback?
Note: I have not perceived any HF variations with my FFA001V3 amps but even if the LPF is covered by feedback, no effect is likely because the tweeters are driven directly by the amp: They are all active systems, no passive components between amp and speaker to change the impedance of the driver. This would be good to know because these amps will be used with passive crossover speakers that do have much greater variations in the impedance curve.
Measurements in posts #521, 522 suggest presence of post-feedback.
While others would base the promotion of their amplifiers on this very feature, you misteriously keep it hidden.
Come on Eric! don't be that low profile.
George
Hi Eric
Ive just seen this. Ive ordered a FFA001V3 with unbalanced buffer board and was planning to use it with a AVC.
Is there a problem if I do this ?
Hi Zeta4
I can assure you, driving Erics input module+FFA001V3 main amp from an AVC works great!
Although it may sound as an overexaggeration, an AVC+FET buffer+ FFA001V3 main amp, competes (acoustically) head to head with a 10k blue ALPS+ N.P. VFET amp (a wonder of an amplifier!).
In fact, in this combination, Erics amp has replaced VFET in my current setup. It drives a Jordan JX92S and a helper woofer.
(JX92 unfiltered. Woofer in series with a 23mH/2.5Ohm coil).
IMO this is an achievement in which both of you have a share.
Eric for the amplifier he designed and built. And You for the technical guidance and material help you offered me to build the AVC.
The final criterion in favor to Eric’s amp, was the LF control it can offer to this load at complex music crescendi (ample power reserves?)
George
I can assure you, driving Erics input module+FFA001V3 main amp from an AVC works great!
Although it may sound as an overexaggeration, an AVC+FET buffer+ FFA001V3 main amp, competes (acoustically) head to head with a 10k blue ALPS+ N.P. VFET amp (a wonder of an amplifier!).
In fact, in this combination, Erics amp has replaced VFET in my current setup. It drives a Jordan JX92S and a helper woofer.
(JX92 unfiltered. Woofer in series with a 23mH/2.5Ohm coil).
IMO this is an achievement in which both of you have a share.
Eric for the amplifier he designed and built. And You for the technical guidance and material help you offered me to build the AVC.
The final criterion in favor to Eric’s amp, was the LF control it can offer to this load at complex music crescendi (ample power reserves?)
George
Attachments
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， so that means I'm the engineer not salesman here！I hope everybody can take it to try and have fun with this amp module~
Thanks
Eric
You give the best advertisement for amp module, I should buy you a beer sometime
