Frugel-Horn Mk3

I understand the Pensil 11 and Horn XL use 6.5” drivers and the Horn Mk3 uses a 4” driver.

P11 is a 6” driver. FHXL was designed with specific attention to the 5.25” A10x.

FH3 typically has a 4” - 4.5” driver. but we have squeezed a 5.25” in. Probably better in FHXL.

FHXL and Pensil are both good, designed by Scott. The FHXL has greater bass gain, goes marginally lower, and is a more interesting shape. Pensil has a more compact footprint.

If you are working with one of Stefan’s flat-paks, the difference in assembly complexity is minimal. The FHXL does have fewer bits to it (largely due to the frame needed at the back to screw the back on).

As had been mentioned, the FH3 probably doesn’t move enuff air to satisfy many of the genres you listen too.

If you need bonkers levels, and bass, you can add the (mostly undrawn at this point) the deflector/stealth woofer to the build.

This is exactly the 2-way approach i would take, and you only need to do step 2 if step 1 (FHXL or Pensil) satisfies your needs.

What kind of amplifer do you have?



New member
2020-10-23 6:41 pm
Thanks for everyones replies. Its very helpful.

I’m not too concerned about having a lot of bass because I have neighbours which I don’t want to disturb too much. Investing in a sub to use during appropriate times in the day will suit me more and can be an option further down the line.

In terms of amps I have a Cambridge Audio Azur integrated which outputs 50w per channel. This is about 15 years old. However this is the start of building a new system and I understand its best to start with the speakers first and then find an amp to match the speaker. I don’t crank my amp too high…..I’d guess about 65 to 70db listening levels.

I’m drawn to the Frugel kits because of the cabinet quality being 18mm birch ply, the cnc machining and ease of construction for a non-woodworker like me. And the quality full range driver means the absence of a crossover. Off the shelf speakers seem to offer much less than this by the time everyone in the supply chain has taken their cut.

I think I’m leaning towards the Pensil 11 because of the smaller footprint.
The Cambridge amp might be more than sufficient in terms of power and sonic quality, and unless it lacks features that you want/need in your “new” system immediately, it’d be the last component I’d think about updating. For me source(s) and upstream signal processing would be higher on that priority list - but of course that’s a whole ‘nother can of worms.

Not surprisingly to anyone familiar with my backstory, I’m a fan of the FH family, but have found the Pensils to be more practical for my particular domestic situation. My current multichannel system has incorporated A10.3s going on 3 years now, and I’m quite happy with them - no doubt the 11s would deliver at least as well.
...Cambridge Audio Azur integrated which outputs 50w per channel. This is about 15 years old...

Certainly sufficient power. I usually recommend min 10w. Given you ar eplanning on upgrading ikely not cost effective unless you diy. I haven’t heard one but they have good cred.

As Chris suggests next up would likely be source. But everything makes a difference.

I listen to the (new) Tangerine Dream with my FH3s and CHP70s a wall of sound from 40Hz upwards at concert volume. Really Great!!


[edit] 10 Watts Hmmmmmm!!! With the amp at waking the dead volume and a full range wall of electronic music. I connected an ammeter in series with the +V output it registered between 0.2 to 0.4 Amps. At 12v = 4.8 Watts divided by 2 = 2.4 Watts less 10% for efficiency wastage = 2.16 Watts or 1/2 that at 0.2 Amps.
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Can anyone advise if these driver specs would be suitable for the FH3 (the Fs is a little higher and VAS a little lower than the usual suspects).

Fs 98Hz
Qe 0.79
Qm 4.0
Qt 0.66
Cms 0.326 mm/N
Vas 2.14l
Mms 8.1g
Sd 69.7cm^2

I appreciate the design is pretty flexible, but most drivers used are lighter with softer suspension. These are some BMR drivers I have sat idle and wondered about making some MDF dust. Would they give me a realistic idea of what the Frugalhorn design is capable of or just not really work?


Paid Member
2020-05-14 5:44 pm
Hi, lots of great info here. I started another thread that would best be picked up here.

I have a pair of these (with the non-upgraded) drivers. They were a fun build, and sound great with anything vocal. However, always looking for the 'next thing':

Fostex BK-12m Folded Horn Kit - Pair

Would I be 'wasting my time' to just get the FH3 vs. going for the XL (with the main goal of getting more and lower bass...within reason, I know these are not bass crushers)? Or will the FH3 with a Markaudio driver give me a big step up in terms of bass compared to the build I have?

Also, what would be the 'best' driver to use (best for me meaning I am willing to trade a little refinement for some more bass)? Is the new 7 MS appropriate for the FH3?

Have an assortment of amps, ACA, Decware UFO2, McIntosh MC275, etc. so plenty of play with there and some nice clean, quality power.

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Would I be 'wasting my time' to just get the FH3 vs. going for the XL (with the main goal of getting more and lower bass...within reason, I know these are not bass crushers)? Or will the FH3 with a Markaudio driver give me a big step up in terms of bass compared to the build I have?

You'll get some really nice bass from FH3s depending on the driver used, but they won't play as loud as the X's, for obvious reasons. If you have a good sized listening room, and want to crank it up, you'll definitely want the the bigger speakers.

Scott designed the BK-12m to fit a specific set of design goals, the over-riding one that it look much like th eBK-16/BK20 (more than 2 decade old designs predating really good modelers).

The FH3 had some sixe restraints, and is not as fine tuned as far as drivers go, but it is really good with drivers within a certain parameter set. The FE126 in your BK12 also works but one has to take maximum advantage of room loading to get reasonable bass.

FH3, even with the drivers you have already, will be better, and with a suitable driver (examples Alpair7.3/7ms/Pluvia 7HD) bass improves, extension improves, even better midrange magic, and a smoother top. A significant improvement expressedny most.

FHXL will play louder, go a bit lower, but usually at the expense of a bit of mid/top extention/dispersion and most importantly detail/DDR when referenced to the smaller drivers. But to exploit that last difference, say between A7.3 and A10.3 since they are very very similar voicing, the stuff in front (source/amp) has to reach a certain level of detail/DDR themselves. And the listener has to value those particualr attributes over that exra bottom, dynamics and potentially greater level.

The FE126 (all FExx6) really want to be driven by a high Rout amplifier. The Mark Audios, in particular, are much more maplifier agnostic. And differences with the damping at the bottom that is provided by the amplifier can be countered by adding more (high Rout amplifier) or less (low Rout amplifier).