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Old School 'Baldwin HiFi' Power Amplifiers Using Modern Components Built to Order.

Historical Archive of Baldwin Power Amps, their development over the past few years and more information can be found here:
Old School Power Amplifier Archive

405c Power Amplifier Reviews

Click this link for Power Amplifier Pricing Stucture

CGI representation of a Baldwin L10 Deluxe Front Panel Scheme (courtesy Mike Toghill)

Each of these stereo Hi Fi Power Amplifiers have the following specifications:
2 case design with plug-in umbillical power connection cable(s) - No Hum.
Old School VU Meters fitted as standard with level adjustment toggle switch.
Input Volume Control (mounted on the rear) to allow use directly with CD players, DAC units and/or Passive/Active Pre-Amplifiers.
Loudspeaker protection circuits - if there is a fault with the amplifier then the loudspeakers will be disconnected.
DC protection circuits - if there is an internal PSU failure on either of the DC rails - both rails will be disconnected thus saving further possible internal amplifier damage.

Tech Specs all units:
220VAC-240VAC 50Hz Mains as standard
NEW - 110VAC 60Hz units available to order
Signal to noise Ratio: 405c = 96dB - L10 = 110dB
Distortion: less than 0.01%
Frequency Response: 20Hz to 20KHz + - 0.5dB

All units are built by hand in West Sussex to order.
Each Amplifier module houses custom ReelAudio circuit boards to suppliment the LJM Amplifier Boards. These boards have been designed using CadCam - the files then sent over to Botech Circuits in Hong Kong who manufacture the required quantities of drilled and plated circuit boards ready for population back here in West Sussex.

By default, everyone wants the "Darth Vader" Black anodised alloy front panels - so main production is geared around these panels. I carry stocks sufficient to allow building your order within 4 to 5 days for the "Darth Vader" versions.
If you require Silver Alloy anodised front panels - then these may have a 3 week lead time for manufacture.

All Units are now built with the Dual Case design - this means that the 'noisy' power supply parts are housed in a separate enclosure - connected by a high current plug-in umbillical cable to the Amplifier main case.
This method means that the Mains Hum Levels are 0dB - no Hum at all!!

The Baldwin range of Power amplifiers use the readily available LJM series of boards which are fine tuned on my test rigs prior production.
LJM Quad 405 LJM L10 LJM L50
405c
L10
L50 (there are 2 of these high power Mono Blocks in 'The Beast')
LJM Quad 405 LJM L10 LJM L50

The Baldwin 405c Amplifier and "The Beast" Power Amplifiers - just to give you an idea of size!.
The 405c and the Beast

The Baldwin 405c and L10 Power Amplifiers now have a 3 hole centred system with 2 x VU meters either side.
Housed in 2 lovely 2307 Chinese alloy cases - Dimensions: 212mm (8 3/8") wide x 257mm ( 10 1/4") deep x 70mm (3") high
Latest production has 2 options for the VU meter functions:
1. 2 x toggle switch with centre loudspeaker protection indicator LED
2. 3 x toggle switch to allow Input and Output Monitoring
405c Speaker Protection LED L10 with Input/Output Monitoring
Top Toggle: Up = Full Power VU Monitoring, Down = Lower level Monitoring
Middle LED: When powered on this LED will light. Once the circuitry senses it is safe, the Loudspeakers are turned on and the LED goes out
Bottom Toggle: Up = VU Lamps OFF, Down = VU Lamps ON.
Deluxe Model of 405c and L10
Top Toggle: Up = Input VU level Monitoring, Down = Output VU level Monitoring
Middle Toggle: Up = Full Power VU Monitoring, Down = Lower level Monitoring
Bottom Toggle: Up = VU Lamps OFF, Down = VU Lamps ON.

The Baldwin 405C.
405C
Amplifier Rear showing Escution Volume control and Umbillical connection
PSU Rear showing External Fusing
405C 405C

The Baldwin L10.
L10
Amplifier Rear showing Escution Volume control and Umbillical connection
PSU Rear showing External Fusing
L10 L10

The Baldwin L10 Mono Blocks.
L10 Mono Blocks
L10 Mono Blocks
Below: 8 x Baldwin HiFi L10 Mono Blocks being installed along with Baldwin HiFi Control Equipment @ Petit Pereyra - a new HiFi Venue in Talamanca IBIZA
8 x L10 Mono Blocks

The Baldwin Hi Fi 1kWx2 - The Beast.
L10
L10
L50 Beast
L50 Beast


Which Amplifier should I choose? The Baldwin 405c or the Baldwin L10?

Here is a short email recently sent to a client to answer the Question.

"Hello George.

I've been developing the Quad 405 clone and the L10 power amplifiers for the past few years.
The culmination of the design has now been developed into the twin case units for both amps.
This negates hums caused by heavy duty toroidals radiating AC 50Hz close to the very sensitive inputs of the Power Amps.

Most of my production is for the Black anodised fronts with meters included. Quantities of pre-CNC'd cases are in stock.
Other variants are now built specifically to order - taking up to 4 weeks for specials (the special non-blacked cases need to be delivered from China etc).

The figures you quote for the L10 are correct in that it will deliver 350Watts into 2 Ohms - although I would not recommend a 2 Ohm consistent impedance at high power for too long.
Remember the impedance of a loudspeaker is variable dependent to the frequency employed.
If 2 x 4 Ohm loudspeakers are paralleled on one amplifier output then the Amplifier will be working very hard. Generally, a nominal 4 Ohm minimum impedance loudspeaker is to be recommended.
Remember, dependent to the frequencies in use, a 4 Ohm loudspeaker can present lower impedance to the amplifier than the 4 Ohm specified.

The Quad 405 Clone delivers 120 Watts into 4 Ohms - around 80 Watts into 8 Ohms.
Although my designs use High Power Toroidals developing plus and minus 50 Volts DC to the rails - the original Quad only had 40 Volts DC on each rail.
Thus my design is capable of delivering 120Watts RMS per channel into 4 Ohms.
The efficiencies (ie: amplifier gain) of both units are similar - they both use the clever Quad 405 current dumping design which makes the units very solid.

With a higher current toroidal in the L10 and the increase in the number of working power transistors - the overall power levels possible are higher with the L10 than the 405.

If the efficiencies of your loudspeakers are low then you will need a higher power amplifier to drive them. These efficiencies may be due to smaller magnet capacity or heavy damping on the cones and spiders - all of these are another subject - where I should write a book.

Remember, the only reason that heavy duty loudspeakers used for public address work or in Discos can take lots of Watts is that they have huge magnets, low damping on cones etc and of course alloy coil formers which can take the heat developed in the loudspeakers when in use. Most Bass units are enhanced by folded horn cabinet technology which almost doubles their efficiency too.

HiFi speakers have been developed with sound quality in mind rather than power capability. The internal crossovers splitting frequencies to each of the drive units is carefully designed to keep the Xover points transparent - therefore dB efficiencies are similar across the frequency spectrum. Thus colouring by the loudspeakers is minimal - and the term HiFi (being there) is more true with well designed loudspeakers.

Also, Power Amplifiers will affect transients within the music.
Normal domestic power levels are around 5 Watts RMS for high/normal domestic listening levels. If the amplifier has more power capability in reserve then sudden changes in the music levels can be catered for without amplifier clipping/distortion.

A 350 Watt capable amplifier will, of course, give more of this reserve power should it be needed - thus although you may not be using the system at anywhere near its' full capability, then it is more desirable to have the reserve in hand.

Logarithmic Scales:
Remember, to double a 1 Watt amplifier (in dB levels) you need a 10 Watt amplifier. To double a 10 Watt amplifier output - you need 100 Watts.
So the difference between a 100 Watt Power Amplifier and a 350 Watt Power Amplifier is not that great - yet transients in the music will be handled a lot better.

I have looked at developing a 1000 Watt per channel unit - yet the production costs for cases, toroidals etc are huge. I do have prototypes in Pre-Production though.
I feel the L10 350 is more than capable to deliver sufficient reserves for all domestic HiFi settings.
The 405 Clone is also good assuming the loudspeakers attached are high efficiency units. The choice is yours George. Both Amps are Good - it depends on what you want out of the amplifier as to which you chose.

My amplifiers are pure analogue old school designs. No computer chips - just pure design for the job intended."


Please Note: There are a lot of crimp terminal and spade terminal connections within each unit.
As well as being crimped these are also soldered for a secure long term connection.

Also Note: Each "Special Version" Unit I am asked to build requires a deposit of 50% sale price prior to works being undertaken.
Usually "Specials" need a 2 week lead time to allow sourcing specialised cases, CNC work etc that may be required.

"Standard" twin case Amplifiers are available from stock (4 to 5 days delivery).

Lots of customers want an Amplifier to suit their specific requirements.
Modifications, additional sections, re-design of other parts are all possible - even specific circuit boards designed and manufactured.
I am very flexible and like a 'challenge'. My electronic and design skills have been built up over 45 years in the analogue world within the Hi Fi and Sound Industry.
Please give me a call or send an email to discuss your "Specials" requirements.

Warranty:

The ReelAudio Custom Built Power Amplifiers are guaranteed for a period of 12 months from the date of purchase.
Normal Usage is implied by the word 'Guarantee' and 'Warranty'.

Click Here to view the Products & Pricing Page.

All Warranty repairs are undertaken on a return to base principle.
Any carriage costs are the responsibility of the Client

REELAUDIO MAKES NO WARRANTY, EITHER EXPRESS OR IMPLIED WITH RESPECT TO ANY PRODUCT, AND SPECIFICALLY DISCLAIMS ALL OTHER WARRANTIES, INCLUDING, WITHOUT LIMITATION, WARRANTIES FOR MERCHANTABILITY, NON-INFRINGEMENT AND FITNESS FOR ANY PARTICULAR PURPOSE. REELAUDIOS' SOLE OBLIGATION AND LIABILITY FOR PRODUCT DEFECTS SHALL BE, AT REELAUDIOS' OPTION, TO REPLACE SUCH DEFECTIVE PRODUCT OR REFUND TO BUYER THE AMOUNT PAID BY BUYER THEREFOR. IN NO EVENT SHALL REELAUDIOS' LIABILITY EXCEED THE BUYER'S PURCHASE PRICE. THE FOREGOING REMEDY SHALL BE SUBJECT TO BUYER'S WRITTEN NOTIFICATION OF DEFECT AND RETURN OF THE DEFECTIVE PRODUCT WITHIN NINETY (90) DAYS OF PURCHASE. THE FOREGOING REMEDY DOES NOT APPLY TO PRODUCTS THAT HAVE BEEN SUBJECTED TO MISUSE (INCLUDING WITHOUT LIMITATION STATIC DISCHARGE), NEGLECT, ACCIDENT OR MODIFICATION, OR TO PRODUCTS THAT HAVE BEEN SOLDERED OR ALTERED DURING ASSEMBLY, OR ARE OTHERWISE NOT CAPABLE OF BEING TESTED, OR IF DAMAGE OCCURS AS A RESULT OF THE FAILURE OF BUYER TO FOLLOW SPECIFIC INSTRUCTIONS.

IN NO EVENT SHALL REELAUDIO BE LIABLE TO THE BUYER OR TO ANY THIRD PARTY FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, PUNITIVE OR EXEMPLARY DAMAGES (INCLUDING WITHOUT LIMITATION LOST PROFITS, LOST SAVINGS, OR LOSS OF BUSINESS OPPORTUNITY) ARISING OUT OF OR RELATING TO ANY PRODUCT OR SERVICE PROVIDED OR TO BE PROVIDED BY REELAUDIO OR THE USE OR INABILITY TO USE THE SAME, EVEN IF REELAUDIO HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

Units are Designed and Hand Built by:
Paul Baldwin
www.ReelAudio.Co.UK
BaldwinHiFi.Co.UK
12 Tack Lee Road
Yapton
Arundel
West Sussex
BN18 0HB - UK - Great Britain
Direct EMAIL: neverfinished0@hotmail.com
Tel: 01243 553231 - Mobile: 07858 089421
Please note: Paul may be contacted by telephone during his preferred admin period of between 5pm and 8pm. Thankyou.

Payment for Goods: PAYPAL Account: neverfinished0@hotmail.com
Please specify what you are buying within the PAYPAL Message Area when Making a Payment.

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