The BA-3 is a power amp. (The BA-3 "as preamp" is just the gain section.) Place a selector switch and pot in front of it and it's an integrated. 😀
Dennis and Jim, I never realized it was actually a power amp.
How many watts will it deliver into a 8/4 ohms with 24V supplies?
Thanks...
How many watts will it deliver into a 8/4 ohms with 24V supplies?
Thanks...
25/50. It's a standard Firstwatt.
However, it scales up beautifully, and you can make it as big as you want. (I.E., until you run out of heatsink... 🙂 )
However, it scales up beautifully, and you can make it as big as you want. (I.E., until you run out of heatsink... 🙂 )
For what its worth, I have BA-3 Amp driven by BA-3 pre and it is fabulous. 🙂
Also have F-5, wonderful driven by BA-3 Preamp as well, like BA-3 Amp better.
Russellc
Looks as though there are more than one option for the output stage.
Is amp the push-pull or single-ended output stage version?
Thanks...
P-P. Output stage is same as output stage of F-4. F-4 front end is a buffer (no gain) whereas BA-3 front end does have gain and makes an excellent preamp by itself.
Thank you...I didn't know this about the F-4 and BA-3.
I'm currently using a BA-3 front end as my preamp. Sound quality pretty much destroys any other preamp/buffer that I've tried.
Just curious what you like better about the sound of the BA-3 over the F-5?
Its hard to say. F-5 is ultra wide bandwidth, transparent to a fault. Most upon building F-5 announce its the best amp they have heard in its power range. Same deal with the BA-3, I once described it as a more mature amplifier, whose sound reflects it. I remember when I was putting the BA-3 parts together, and discussing other F-5 builds I would like to try with 6L6, he told me that once I built BA-3, I would be done building F-5 amps. He was right in my opinion.
Many also say, and truthfully so, all the Pass amps are excellent which I agree with. The F-5 so pleased me, I sold a Mcintosh MC-225 I swore would have to be pried from my cold dead fingers...BA-3 even more so.
BA-3 has been said to be a combination soundwise of the F-4 and the F-5, and I suppose its true. I prefer it to the F-5. One thing we both seem to agree on, BA-3 as pre KILLS as a preamp! Using that pre with the BA-3 Power Amp and the Pearl 2 is the largest jump I have made in sound quality in some time.
6L6 also told me the Aleph J is unbelieveable good and I must build it. I have its boards assembled, everything except the chassis....then he told me the F-6 is crazy good, so I also have it ready to go, except the chassis...hopefully I will get 2 4U boxes before F-7 is released...🙂
Russellc
Thank you for the detailed comparisons.
Personally, I haven't built any of Nelson's power amps and have always used commercial Class AB offerings most of which use BJTs for the output stages.
I purchased an Adcom GFA-5300 MOSFET amp a while back, curious about Adcom's older MOSFET offerings, but IMHO its sound doesn't compare to most of the BJT amps that I've owned.
To my ears, there's just something missing in the 5300's sound, or perhaps the sound is just too "laid back" or "sterile" for my taste...really hard to pinpoint.
So I'm really anxious to try a Class A design like the F-6.
I already have the boards, transformers and most of the resistors for the F-6.
The case is the big hang up for me since I don't have one.
After what 6L6 told me about the Asian cases, I feel I need to save up for one from the DIY Store or purchase a couple of large heatsinks and go from there.
I have decided on the F5 and the BA3 as a preamp. I should have all the parts (minus enclosures) in the next couple of weeks. I am going to stuff boards and go from there.
I was wondering if someone could be so kind as to share a digikey link to the preferred LED? I have spent quite a while trying to sort through there and I can't seem to find it.
Also, is there a current BOM for the Super Regulator PCB. I purchased the one that was on sale and is now sold out. I want to get those parts ordered as well and can't seem to find that BOM. The link on Jan's site is broken.
I was wondering if someone could be so kind as to share a digikey link to the preferred LED? I have spent quite a while trying to sort through there and I can't seem to find it.
Also, is there a current BOM for the Super Regulator PCB. I purchased the one that was on sale and is now sold out. I want to get those parts ordered as well and can't seem to find that BOM. The link on Jan's site is broken.
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LED - cheapest green or red or whatever color you like
those are generic parts , not influencing sound quality
( I know , ZM speaking sacrilege ....
)
those are generic parts , not influencing sound quality
( I know , ZM speaking sacrilege ....
)F-6 is next on my build schedule. Whichever Pass amp you build, you will find it will better your previous amplifiers just like the BA-3 Preamp bettered your other preamps. You are in for a treat.🙂
Russellc
IR and red are the lowest voltage (Vf) LEDs.
Green, orange and yellow are usually significantly higher Vf.
White and Blue are very much higher Vf and are reputed to be noisier than the low Vf versions.
If the circuit needs high Vf then you must use the High Vf LEDs.
But most circuits use a low Vf LED and then any can usually be used.
But don't try to run them at maximum current.
A 20mA LED will not last long run at a continuous 20mA.
Try 1mA or 2mA and see what brightness it gives and choose a suitable brightness @ <10mA.
Hi.
What Pass amp to build to drive my B&W 802D speakers? They need some current. Any advice, please?
zz
What Pass amp to build to drive my B&W 802D speakers? They need some current. Any advice, please?
zz
With 90db sensitivity the F6 would be a good choice depending on how loud you like to listen and the size of your room. It is the latest offering from Mr Pass for diy. Watch this video.
https://www.youtube.com/watch?v=pdw7esZBbXE
https://www.youtube.com/watch?v=pdw7esZBbXE
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