JR149 speaker

Introduction
JR149 MkI
JR149 MkII
Review
Sale Results at Auction
JR149 Accessories
JR Super Woofer
JR DW2 Woofer
JR150
JR Metros
JR Phobos
Links

Introduction

Jim Rodgers worked as an engineer for the BBC. In 1977 he establish the company named after him, JR Loudspeakers Ltd to manufacture a design he based upon the BBC LS3/5A, the JR149, using the same drive units but housed in a heavy gauge aluminium cylinder with wooden end caps. There is a bolt through from top to bottom to brace the enclosure and make the wooden ends slightly concave, thus eliminating flat panels. The enclosure was lined mechanically and acoustically to reduce sound radiation from the cabinet.

JR speakers where originally distributed by Tape Music Loudspeakers Limited, 114 Ashley Road, St. Albans, Herts ALI 5JR.

JR149 MkI

The original design used the same 15 ohm drive units as on the LS3/5A; a Kef T27 (sp 1032) tweeter and a B110A (sp1003) bass.

The JR149 is classified as being in three versions; the red logo on the bottom plinth, the gold on black logo also on the bottom plinth and the MkII where the logo is a plastic rectangle that was glued to the speaker foam. Less easy to spot are the changes in drive units and cross over circuit. The last cross over unit was "Type 24" on a square circuit board.

The red and gold logo versions where advertised as having a wide range of finishes to the top. These included veneers in teak, walnut, rosewood, oak and also with red or green inlaid leather. Less common are the piano black, aluminium and gold finishes.  The bottom wooden disc is black or a matching colour to the top disc but may be, as in the MKII, MDF donut with the cross over inset into the disc, not totally contained in the metal plinth.

LS3/5A where manufactured by several companies to the exacting specifications of the BBC. Even so listeners to the variations claim differences in performance. The JR149 is claimed, by comparison to have more bass and are thus preferred.

JR149 Mk II

When the company moved to Unit 5, Morewood Close, Sevenoaks, Kent the mark II was introduced. The Kef drivers are replaced with a 110 mm bass unit Frocal and the tweeter from Scanspeak, a 19mm doped fabric design based upon D200.

The external style changed slightly. Gone is the black strip that hid the ends of the covering ribbed foam. The foam covers are continuous with no visible join. When replacements are used the ends have to be pulled in and double sided tape used to make the join. The logo is now a plastic rectangle glued onto the foam.  The large gold on red or later black labels on the base are replaced by a small black rectangular one.

Review

The basic characteristics of the MkI and MkII speakers are identical. The only observation that notes the difference is that it takes more volume to get a pair of gold logo MkI to emit a sound than on the MkII speakers.  The specification for the original JR149 gives the efficiency as 89dB and that of the MKII as 84.5dB for 1 Watt. The difference could also be down to the particular pair of gold label JR MkI that I have where one speaker remains silent until the volume is well turned up but is then at the same volume level as it's twin. When balanced to the same volume level only the most discerning hi-fi buff will find a difference in the two pairs but may not determine which are the MkI or MkII speakers.

The original rosewood gold label MkI speakers, purchased in 1978, where powered by a Cambridge P80 40 watt amplifier. The volume level had to be high to get these to speak. It was not a good match. The Cambridge powering a pair of Kef 104 was much happier and far better sound. Matching the JR149 to Meridian 105 100 watt mono amplifiers gave the power and control that the JR149s needed and proved that these speakers are hard to beat.

The walnut MKII, purchased in 1982, where matched to a Uher Miniline system with 60 Watts into 4 ohms. Unfortunately this system has an Achilles heal, the power amplifier two large capacitors kept blowing out. The replacement amplifier was a Meridian MCA (Meridian component amplifier) with 35 Watts power. The Meridian is an excellent amplifier but under powered to get the JR149 showing off what they really can do. The Super Woofer helped considerably and the MKII where better controlled at the lowest volume than the MKIs. For modest living rooms a quality 30-35 Watt 8 ohm amplifier such as the Quad 303, Meridian 101/103D and MCA integrated amplifiers are perfectly acceptable. For the highest volume levels a 60 watt 8 ohm amplifier is needed. Any of the 100 Watt amplifiers from Meridian from the 105 mono to the 5 channel G55 are going to make easy work of powering the JR149 but don't turn the power full up. There are claims that the 105 driving at full volume blow out the original JR149 speakers which do not have fast blow fuses.

Faced with two pairs of JR149 and wanting to experiment with a surround sound system from TV and DVDs a new (2006) Meridian G55 5 channel 100 Watt amplifier was obtained. The amplifier is controlled by an external sound card from the computer, a Terratec 6Fire USB. With 3 pairs of JR149 (2 pairs of rosewood MKI and a pair of walnut MKII) but still having to obtain an additional sub woofer the experimentation is not concluded. The Meridian G55 powered JR149 are impressive. They look as modern as they did when first made. They sound impressive and demand to be listened to. In this configuration the Super Woofer is used with a pair of JR149 as front channel so that when used for stereo they have the full range. In 5.1 surround the centre speaker provides much of the dialogue and sound stage and hence needs to be a good match for the front pair of speakers. The rear speakers can be identical to the front pair or of lesser detail. The Super Woofer is feed by the speaker outputs from the amplifier and so can not be used as an active sub woofer in the 5.1 system.

The JR149 are among the best looking speakers ever made. At this size there are few that out perform them when matched with the right amplifier. Only much larger speakers, and active speakers where the amplifier are designed for the cabinet and drive units may better them. None are more acceptable in a modern living room. This may explain why they are so activity followed and bid on at auction.

Sale Results at auction

Most JR149s offered for auction lack the foam covers or have taken replacement from Wilmslow Audio or ribbed replacements from Graham Hartle. Some have put inline banana plug sockets or replaced the cable with a gold plated banana sockets drilled and fitted to the metal base. With second hand goods at auction condition is paramount as is the number viewing the auction with the desire to buy. Prices range from £140 to £600 with the majority being sold in the £180-320 range. Local, classified advertisements have turned up speakers for £50-100. In general the red logo original versions sell for more and no one realises the true MkII compared to the gold label version of the MkI. MkII are very rare. There are no details on the serial numbers. It would seem than anything below 6300 is likely to be a red logo version and anything from 6300-24000 has a gold logo. The MkII seem to lack a serial number label.

JR149 accessories

There where wall units made for the JR149. These are black painted metal bands, the depth of the black metal base with rubber inserts to protect the speaker physically from marks and acoustically from vibration.

Small stands where also sold. These are extremely rare now.

JR Super Woofer

The Super Woofer looks like a JR149, but in the form of a small coffee table on castors. The top came in a range of finishes to match the JR149. It uses a 10 inch Audax bass surrounded with foam.

There was a passive version with the terminals for the satellite JR149s coming from below the super woofer unit.

The owner of the unit (above) removed the electronics from below the super woofer and built it into a box. There is no mains power to this low-loss crossover unit.

The active version used an amplifier in a brown box with large heat sink fins with an on/off and a 'volume' control for the bass.

With the mains powered LPA (Low-pass filter with Amplifier, above) the satellite and super woofer where connected to this. Low frequencies passed to the super woofer and higher frequency to the satellite JR149. The nominal 30 watt amplification allowed the JR149 to go to higher volume levels with out strain or damage.

The EX1/PA60 (below) was designed to work with separate pre-amplifier and power amplifier. It has a low filter cross over from the pre-amplifier leaving the power amplifier to connect the JR149 speakers to and the PA60 to handle the super woofer. [Photographys courtesy of Chris Yates]

A later mk3 bass amp was added in the 1990's,  a room correction equalizer (professional type) when adjusted frequency and Q was introduced in the 1990's.

 'JR' BASS AMPLIFIER MKIII is an active 30W crossover mono amplifier designed originally to add BASS to the JR149 range of speakers. This unit will divert the bass frequencies, from 100Hz down to 20Hz) to the Super Woofer.

The left control knob is the Slope Control:- which lifts the extreme low bass so compensating for the natural roll-off of most woofers.
The right control knob is the Gain Control:- to set the correct level of bass relative to the main stereo loudspeakers.

 30 watts into 8 Ohms,  24Db per Octave slope controllable. Suitable for any speakers 4 to 16 Ohms.

JR DW2 Woofer

The DW2 subwoofer a rare unit which used 2 seas 10" drive units in pushpull. 

JR150

The JR149 is a small speaker and getting good bass from a small unit is hard. Taking the aluminium cylinder enclose features of the JR149, the taller, floor standing, JR150 uses an audax 1" tweeter and two 110mm bass Audax HD13B 25H-2C12 16 ohm units.  Much larger and more expensive and with stronger competition these where not as popular as the JR149.

JR Metro

Metro was a small shoe sized square box speaker with rounded edges and finished in Nextel.

JR Phobos

These where developed in the 1980's and where a wall hanging speaker which looked like a tambourine.

LINKS

http://www.jr149.pwp.blueyonder.co.uk/JR149%20History-3.htm

http://www.davedixon.co.uk/daves/jr149.htm

http://homepage.ntlworld.com/hon.lau/JR149.html

JR149, JR150, Super Woofer brochure

Wilmslow Audio - for replacement JR 149 parts including plain acoustic foam

Last updated 6th June 2010