Audiophile realism from a no-compromise hi-fi loudspeaker design.
Our original audiophile design, evolved to become the ultimate in leading-edge impulse precision.
The heavy rolled-steel tops provide isolated supports for the HF units. They are precisely offset, and matched to unique patented crossovers to present a single acoustic wave-front to the listener.
20cm LF units and 28mm HF units give 550 watts from below 20hz (as measured by Hi-Fi Choice), to 22kHz.
That deep integral bass is rock-solid, with no loss of control, whatever is thrown at them.
The units shown left are in Black cloth and Metallic Gunmetal steel. They are a visual statement in uncompromising audiophile hi-fi loudspeaker design.
Extended mountings for the spikes increase the footprint area by 20 percent, and the rear of the top steel also acts as convenient handle for these large speakers.
Dimensions. 107cm high x 22cm wide x 25cm deep, and 20Kg each.
Purity and power. Power handling is 300 watts continuous, 550 watts maximum, and 1,500 watts for 10ms. And there is no loss of control when that bass power is used.
Frequency response. Is from below 20Hz (as measured by Hi-Fi Choice) then up to 22kHz.
(Shown right) Set into the front, are steel vibration-damping bars. They are handed and optimally placed to break up front-panel resonances.
They can be internal, or optionally external (as pictured) in a finish to match the main steels.
Sensitivity. Sensitivity is 90dB. This is combined with high efficiency, so that one Norwegian customer is delighted with using a six watt single-ended valve amp. Look at the comment from Norway here. (Scroll down.)
A UK customer, Kevin McHale, gave us this feedback.
"I particularly like the fact that they work well with my modestly powered Altmann BYOB amp, which is a 10W battery powered amp, but which creates more than enough volume for me through the As."
Impedance.
This is a valve amplifier friendly easy drive of 8 ohms nominal, with a minimum of 6 ohms. This also makes them less sensitive to differences between solid-state amplifiers.
Despite the Norwegian report, we recommend valve amplifiers have a minimum of around 18 watts, and solid state amplifiers around 35 watts.
Drive units.
The HF drive units are 28mm diam, silk domed, with neodymium magnets and ferrofluid-cooling. They are rated at 500 watts for 10ms and are separately mounted within the rolled steel tops (shown right)
The LF units are 200mm, 8 inch, Kevlar-coned, and only 20mm smaller than the slim enclosures. They have 4 layer voice-coils and 40oz magnets, to give rock-solid 20Hz bass, which remains tight and fast right down there.
Crossovers.
The drive units are coupled with patented asymmetric crossovers, which use only film capacitors and air-spaced coils.
They are accessible, mounted on the inside of the terminal panel. (Shown left)
The HF circuit is fourth-order, with 24dB per octave attenuation from 3kHz. This gives superb protection of the HF units.
The LF crossover is first order, using only the voice-coil inductance, for absolute purity.
So for Hi-Hi News, "High frequencies were richly detailed, ensuring that instruments buried way down in the mix are clearly discernable as individual".
And for Hi-Fi + it is "the sheer speed and integrity of its music making."
For What Hi-Fi "rhythmic integration of instruments is seamless, allowing you to identify individual strands with ease."
For Hi-Fi Choice "The first thing one notices is just how coherent and 'real' it sounds. Timing is truly exceptional."
And the quality recently astonished two Scottish customers, Gordon Anderson and Neil Wallace:
Hi Allan,Click or scroll down for more specification and usage details Click for All the Model A reviews
They sound fantastic. Extremely open and musical. Wonderful to listen to. With 45 watts of valve class A the sound is stunning, fast and agile, filling the room with sound well beyond what any other manufacturer offers for anything like this price. I have had over 60 pairs of speakers and these offer all of what I want. To say I am pleased is an understatement ! many thanks, Gordon""Good evening Allan,
Your speakers gave me a constant grin and almost a tear on some tracks. I was a musician for 35 years and always strived to find Hi-fi equipment that would produce the timbres of different instruments, but speakers have always been the final let down - till now. These are just wonderful. I can distinguish the tonal quality between a Boosey and Hawkes and a Yamaha Xeno Cornet. Listening to jazz, saxophones is sublime, leaving the hairs on the back of your neck standing up. The bottom end is endless. They go deep and stay tight with no bass overhang at all. I look forward to many happy listening hours, knowing my search for speakers is now over. Thank you for producing such a lovely musical experience. Kind regards, Neil W.
For full surround-sound with the fantastic MonoPulse realism, in a matched and balanced system, we also offer centre and wall units based on the high specifications of the 250 watt, Model C. The total system maximum power is 1,850 watts.
Model CM - Centre unit, 45cm wide x 19cm high x 22.5cm deep.
Model CW - Wall mounting units - 35 high x 18cm wide x 20cm deep.
Floor mounted Model S or stand mounted Model C pairs can also be used as rear units.
Our dealers will negotiate on price for any surround-sound sets.
Return to the top Or Return to Home
See below for more specification and usage details.
The Model A - use and specification details.
Design Objective.
All MonoPulse loudspeakers have the primary objective of realism and precise imaging by time-domain synchronism of the impulses and musical leading edges in sounds.
The Model A is also a top quality hi-fi loudspeaker in all other respects, featuring 550 watt maximum power and a bass response down to below 20Hz.
Description.
To achieve this realism, MonoPulse uses a unique technique, precisely offsetting its drive-units, then combining them with a patented asymmetric crossover, using only film capacitors and air-spaced coils.
The HF circuit is fourth-order, with 24dB per octave attenuation from 4kHz. This gives superb protection of the 28mm, ferrofluid cooled, silk domed, neodymium magnet, HF units, which then operate up through to 22kHz.
The LF crossover is first order. The Kevlar cone 200mm, 8 inch, LF units, with 1 kg magnets, have 10ms transient power handling of 1,500 watts, and nominal power handling of 550 watts. They are housed in generous box volumes, and the bass response is extended with a reflex tuning point at 32Hz, giving an in-room response down to below 20Hz.
Handling. The back of the top steel can be used as a handle, through the gap in its rear foam.
Positioning for bass.
The centres of the LF units are 85cm from the floor. Try to avoid having the front of the speakers also 85cm from side walls or rear walls. If one has to be less, try to make the other one greater. Close to a rear wall is OK, if they are about 1.5 metres or over from side walls - or vice versa. But remember that probably 80% of speaker installations are not able to fully comply with these guidelines - so treat them as a help to achieving the best in any situation - not an absolute rule.
The bass alignment is sub-flat, to meet the likely preferences of audiophile equipment owners, but if there is unwanted bass emphasis, we can supply (FOC) bass damping adaptors to be fitted in the downward-firing bass ports.
Position and imaging.
A normal placement is with the units about 2.5 metres apart at a listening distance of about 3 metres. The MonoPulse impulse accuracy will also allow the units to be further apart or closer in than normal. This can give a dramatically wide sound-stage presentation, while the MonoPulse precision maintains accurate central imaging. Some users liken this wide separation to surround-sound - but without the irritating noises from behind. This ability can also be useful if there are positioning problems, particularly in small rooms.
Adjustment for HF response.
It is a by-product of impulse accuracy that these speakers are quite directional and ‘sweet spot’ in character. This does mean though that the upper-register subjective response can be adjusted, either pointing the units directly at the listening position for maximum treble, or more parallel to reduce it.
Adjustment for Listening Height.
The Model A focus of time-domain synchronism is optimised for listening at a height of 90cm – perfect for a low sofa or chair. For a higher position, exact acoustic focus can be made by tilting the units slightly backwards. A 5mm front/rear spike length difference, raises the focus by 10cm at 3 metres distance. Otherwise they will perform as normal hi-fi loudspeakers.
The spikes can be used to slightly adjust bass response. Shortening will give more emphasis but less extension - and vice versa. The normal range is for the base of a speaker to be 40 - 50mm from the surface below it.
We can supply extra-long spikes for more extreme adjustment or for clearance and stability on thick carpets.
Alternative nylon "spikes" with rounded ends can also be supplied which are more suitable for hardwood floors.
Cables and Connections.
The terminal panel will take 4mm plugs, 7mm spades, or 5mm bare wire. If using plugs, for quick temporary connection, remove the coloured bungs, but for permanent placement use the holes in the posts and lock the plugs down with the screwed caps.
The HF terminals are the upper ones, the LF the lower, and the units can thus be bi-wired or bi-amped.
The interconnection cables needed, will depend on the system and the layout - please consult your dealer.
Running in.
We recommend that the speakers are run in for at least 50 hours at the intended listening volume, with occasional spells at a higher volume.
Warranty.
MonoPulse loudspeakers are covered by a one year warranty.
Repairs.
In the unlikely event of overheating damage to an HF unit which is protected by a fourth-order filter, access is by removal of the upper cover. This can be done from the back, by pushing a rod through the gap in the rear foam.
There is no removable cover over the LF unit, but this and the cloth can be replaced at the factory or by a competent repairer.
For spare HF units and other repairs, contact your dealer.
Other specifications.
Nominal impedance 8 ohms, minimum 6 ohms.
Power handling, 550 watts maximum, 300 watts continuous, and 1,500 watts for 10ms.
Sensitivity, 90dB.
Height, 107cm. Width, 22cm. Depth, 25cm. Weight, 20Kg per unit.