still enjoying it daily, brought it into work and it keeps the zoom chats clear as well as playing music to keep me motivated throughout the day. Putting my SIT amp back into play at home was a humbling experience to highlight the difference in sound. The FH9HVX is like the energizer bunny while the SIT is a graceful blue whale sailing through the ocean. The increased resolution and microdetail with the SIT made me stop working quite a few times. I still love the sound of the FH9HVX and would encourage anyone to build it - build cost was 1/10th of the SIT and it performs 90% as well.
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I have actually come from the other side. I used to use 200W amps, then dropped to an 80W amp and finally started playing with more serious Class A and at low listening levels or nearfield monitor ( my 2 general circumstances ) the 25W Class A amps seriously outclass any AB / Class D etc amp that I have tried. Not all people feel that Maggies can sing with 25W but this has not been my experience and my desktop monitors produce a deep articulated sound with Class A. I probably will not be filling a dance hall with my monitors but I don't need to. Would I feel differently with 200W of Class A - perhaps, I have never owned any behemoth class A amplifiers.
A similar argument was made about headphones which is why we see 5-7W output into headphones from some amps, I still own the very first planar magnetics ever made by Wharfedale and they do just fine with humble amplification. anyway, I digress, I very much like what this amp brings to the table and it surprised me by how articulate it is as well as having the power behind the bass response. Easily on par with the Linn Klout amplifiers I used to own.
A similar argument was made about headphones which is why we see 5-7W output into headphones from some amps, I still own the very first planar magnetics ever made by Wharfedale and they do just fine with humble amplification. anyway, I digress, I very much like what this amp brings to the table and it surprised me by how articulate it is as well as having the power behind the bass response. Easily on par with the Linn Klout amplifiers I used to own.
If you allow a slight diversion, could you elaborate on “your SIT” amp, please. I don’t recognize the name. Also, what specs for the amp and your speakers.
Hi and sure
The speakers are a combination of the Monsoon planar panel and a tangband longthrow 5" woofer in the Optimus LX5 cast aluminium housing.
It was a happy experiment that turned into a surprisingly good monitor - I wanted the Linaeum driver from the LX-5 for an OB experiment and as I had these well crafted boxes I thought I would try something different. The original drivers needed to be refoamed and weren't that impressive so I looked for a suitable driver and the FR of the W1138 looked promising. I ended up playing with the crossover and some internal damping in the chassis and it produced a well balanced sounding speaker with a tight and deep bass response. - purely lucky chance that it worked.
The amplifier is a ZenMod version of a Nelson Pass amplifier - M25 ( basically a beefier version of the M2 ) or possible to use Static Induction Transistor (SIT) which emulated a SIT3 like Class A amplifier. The details of the mad scientist are in this thread
There is no apples to apples here, which is why I think the FH9HVX is a great amplifier. I have since moved it into my office at work where it drives a pair of vintage Pinnacle bookshelf speakers and sounds very good.
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The speakers are a combination of the Monsoon planar panel and a tangband longthrow 5" woofer in the Optimus LX5 cast aluminium housing.
It was a happy experiment that turned into a surprisingly good monitor - I wanted the Linaeum driver from the LX-5 for an OB experiment and as I had these well crafted boxes I thought I would try something different. The original drivers needed to be refoamed and weren't that impressive so I looked for a suitable driver and the FR of the W1138 looked promising. I ended up playing with the crossover and some internal damping in the chassis and it produced a well balanced sounding speaker with a tight and deep bass response. - purely lucky chance that it worked.
The amplifier is a ZenMod version of a Nelson Pass amplifier - M25 ( basically a beefier version of the M2 ) or possible to use Static Induction Transistor (SIT) which emulated a SIT3 like Class A amplifier. The details of the mad scientist are in this thread
There is no apples to apples here, which is why I think the FH9HVX is a great amplifier. I have since moved it into my office at work where it drives a pair of vintage Pinnacle bookshelf speakers and sounds very good.
..dB
The dipoles are Monsoon MM 2000, no sub. I don't recall exactly where the crossover ended but it is around 450.
They sit about 3feet away on my desk. Massive soundstage with pinpoint imaging. The 5" obviously doesn't rattle the floorboards but as near field with low spl, they provide a very real balance.
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They sit about 3feet away on my desk. Massive soundstage with pinpoint imaging. The 5" obviously doesn't rattle the floorboards but as near field with low spl, they provide a very real balance.
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I agree that a 5in woofer provides plenty of bass as a 3ft nearfield monitor. I tried my Foamclone LS3/5A as computer monitors today and was amazed at the soundstage, imaging and bass that they provided.
On top of a desk, there is real boundary enhancement of the bass below 100Hz.
RST28F and DC130A Foamcore Homage to LS3/5A
These worked out so well, I am getting two sets made up in BB ply and white oak and maple battens (beech will take a month to order):
On top of a desk, there is real boundary enhancement of the bass below 100Hz.
RST28F and DC130A Foamcore Homage to LS3/5A
These worked out so well, I am getting two sets made up in BB ply and white oak and maple battens (beech will take a month to order):
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I think that is what mine cost sans the sub. I spotted these recently but I really should not be buying more speakers - just as well I don't live close enough. Because they are all getting a little old , one thing to watch for the the "grattle" - dust or other dirt between the magnets and the diaphragm, not the easiest thing to completely sort out.
Geez! you guys need to slow down, too many cool projects and I'm slow, slow, slow.
What problems to have!
OMG yes this!
How am I going to find the time (or money!) build an Aleph J, Alpha Nirvana or ABBB, DCA, maybe a TPA3255, Korg B1, and now this FH9HVX...after build my ACP+ and restore my Fisher 500c?!? Not to mention, all the other cool and interesting designs that I'm sure you/AKSA/JPS64 and Nelson will come up with by the time I get to all of the above. I'm going to need a couple more lifetimes at the rate I complete DIY projects!
That’s why I have been making mostly speakers lately.
We have new little stuff in the pipeline though. A cool new ultra low noise preamp/DAC PSU (+/-5v, +/-12v, and +/-15v) called the Vpower, a breakout test board for Yarra/M2X format daughterboards, a new SSR speaker protect with remote shutoff and also instant shut-off to prevent speaker turn off thump, a new headphone amp based on the OPA1656, and more. We don’t have enough time to test and build the verification boards.
We have new little stuff in the pipeline though. A cool new ultra low noise preamp/DAC PSU (+/-5v, +/-12v, and +/-15v) called the Vpower, a breakout test board for Yarra/M2X format daughterboards, a new SSR speaker protect with remote shutoff and also instant shut-off to prevent speaker turn off thump, a new headphone amp based on the OPA1656, and more. We don’t have enough time to test and build the verification boards.
Wow nice! Could that power supply be used for a phono stage as well?
And how will your new speaker protection circuit differ from the current RTR SSR DC Protection board for sale in your shop?
The PSU ideal for any low current (<70mA) ultra quiet requirement like preamps, DAC output driver, and phono preamps. The new SSR protection board will have same footprint so it can be swapped out but allows for use with bridged amps where there is DC on both outputs but net zero DC and also allows instant cutout using remote logic.