The recent audition of a Forte Model 4 in my system was sort of a revelation to me, and a step in the learning curve of how amplifiers and speakers work together. Thirteen years ago I built my first diy amp, a Zen V1 assembled on perf board. Next came the FirstWatt F5, and other iterations of the FW amps followed. I’m not a speaker builder, so the first speakers I had were a pair of B&W DM305, next a set of Focal 826W, and finally a set of Focal 1028BE. The core of my system has always been the FirstWatt amps at ~25 watts output. Now that I’m using the Model 4 with 50 watts available it’s apparent to me that my conventional speakers need more “muscle” for lack of a better term. I don’t understand that because for the most part the speakers are only using a fraction of that power most of the time. The Model 4 is a very nice sounding amplifier and seems to take control of my speakers. The mid’s and hi’s are not as smooth and sweet with the Model 4 compared to the FW amps, but the mid and lower bass sound much deeper and stronger. So now what? I’m contemplating the construction of an F5T. So is a 50 watt stereo enough or are 100 watt mono-blocks going to be better? It certainly has been a fun and gratifying journey to this point with much more learning/building to come.
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I can't say I could be too much help but I love my 250w per channel amp even though I hardly use any of it. I would say if it isn't too much more effort or expense, the 100w mono blocks would be my choice just to know I have it.
Imho better way to go is sensible efficient speakers , the key for the best natural sound
source : http://www.firstwatt.com/pdf/art_cas_2015.pdf
Oswald Mill Audio
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My Nak PA-5 (150 watts per channel) can drive my 96db Klipsch speakers like Ben-Hur drives a chariot from 20-20000 with great clean control. My 13 watt tube amp has less power/control over the bass but sounds so sweet that it makes you want to listen all the time. I have done this same test with Usher Dancers which I would consider similar to your Focals and the additional power of the Nak woke the Ushers up. A Threshold 400 or 800a? F5 monoblocks? Feed the Focals, no bad choices here...
Inevitably someone will say buy or build more sensitive speakers. I won't say it. 🙂
A pair of F4 stereo amps can be wired for 50w or 100w. Just need a high gain preamp capable of 20db of gain.
I recent built a twin triode preamp capable of 30db of gain. It's easily adjustable via two resistors.
I upgraded the kit parts and it still cost around $200. Hard to believe the sound.
Point is a couple F4s are very versatile.
A pair of F4 stereo amps can be wired for 50w or 100w. Just need a high gain preamp capable of 20db of gain.
I recent built a twin triode preamp capable of 30db of gain. It's easily adjustable via two resistors.
I upgraded the kit parts and it still cost around $200. Hard to believe the sound.
Point is a couple F4s are very versatile.
BA3 with 30 volt rails gives 50 class A watts if you build it like 6L6's build guide. Or build 2 of them and wire each amp as a mono block (BBA3) and get 100ish watts.
Russellc
Russellc
Yeah, I hear you. Klipsch forte II here.
I LOVE my M2 clone (and aleph etc), but sometimes the Threshold s/500 is called for. The power just seems to grip the speaker.
It's a mood thing.
I LOVE my M2 clone (and aleph etc), but sometimes the Threshold s/500 is called for. The power just seems to grip the speaker.
It's a mood thing.
There are other SE Class A amps on DIYA (in the Solid State Forum) that provide 40w to 50w of power. They definitely sound more powerful than typical 25w Class A amps. Especially if you have multi-way speakers that are not super efficient.
For sure...I’d like to get my hands on that and give it a try! Maybe my buddy who owns a stereo shop will get one in some day. That’s where I got the Model 4 on loan from (Wayback Audio).
I have an F4 and BA-3FE preamp and enjoy that combination. I’ll consider building another.
I like that idea as well...wondering what that would sound like driven by the Korg B1?
I get that it’s a mood thing...but if I could get the smooth sweet mids/treble AND the deeper/controlled bass, that might suit my mood more often.
Well, with FW and clones, try couple of things:
1. Replace all 0.47ohm (or so...)/5W Panasonic resistors with wire-wound types. That means power supply and the amplifier PCB's.
2. Replace the input hook-up wire with annealed silver ribbons. There's no need to twist them at all, i.e the ribbons don't need any insulation.
1. Replace all 0.47ohm (or so...)/5W Panasonic resistors with wire-wound types. That means power supply and the amplifier PCB's.
2. Replace the input hook-up wire with annealed silver ribbons. There's no need to twist them at all, i.e the ribbons don't need any insulation.
Any of the S/ series is great. I would think that his first watt stuff surpasses Threshold.
I am on this forum because I am looking into building a preamp. I know very little about amps however.
Good luck with the hunt for more power.
Is that the same B1 amp that is in the that is in the "The diyAudio build guides" thread? From what little I have read, the BA-3 seems to be favored. One guy said he threw his B1 in the trash because I he liked the BA-3 so much. Who knows if he was serious.
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I’m using the F5 turbo v3 built as monoblocks. 125w/ch 8 ohms with 70w in class A -400w into 2 ohms. I am using a Jensen input transformer to get balanced input capabilities. I am running a pair of Monitor Audio gold 300 speakers (4th generation) which are 4 ohms and 89db rated. The monoblock F5 amps sound superb and have finesse, detail, slam and resolution that make them my go to amps for most listening.
I have an Aleph J also which is a bit softer on the top end but lacks the bass grip of the larger amps.
I have an Aleph J also which is a bit softer on the top end but lacks the bass grip of the larger amps.