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Passive
Active HeadPhones VU RIAA
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The T90 Large Meter PreAmplifier and Power Amplifiers.

Specifications.
9 x stereo inputs selected by cascaded Toggle switches - Input 9 has a RIAA MM Preamp inbuilt.
100k Ohm input impedance - each input level adjustable.
Passive & Active PreAmplifier.
Switch into Active Mode then the Super Valvey Mullard sound kicks in including huge Bass / Treble control sweeps

3 x Tape Recorder Inputs and Outputs (Record to all machines at once and monitor each machine whilst recording (3 Head machines only)
2 x Headphone Outputs with Volume control and switch to disconnect the Power Amplifier for Headphone listening.
High Quality logarithmic Volume Pot
3 x Variable stereo output sockets to drive extra Power Amplifiers

The Power Amplifier is my version of the famous 405 current dumping amplifier - delivering up to 120Watts RMS per channel.
There are 2 sets of Loudspeaker connections using 4mm Banana sockets.
The connections marked "Main" are directly connected to the Internal Power Amplifier via the protection circuit.
The connections marked "Aux" allow additional Loudspeakers to be connected without affecting the Impedance load to the Amplifier.
The Power Amplifer protects the Loudspeakers with a Soft Start and Close circuit.

The lower case is the Linear Power Supply. This connects to the top case by 2 Umbillical cables.
The VU Meters in the LPSU Case monitor the Power Amplifier Output Levels.
The Vu Meters in the Top enclosure monitor whichever source is selected.

The Inputs and Outputs
Inputs and Outputs clearly marked.
The Inputs and Outputs
Each input Phono/RCA connector has a 16 way multiturn trimming potentiometer.

The RCA/Phono Board has input trimmers allowing you to attenuate the input for the following reasons:
Let's assume you have a CD Player and an old HiFi Tuner as musical sources.
The Tuner will have a Stereo Output of typically 150mV per channel.
The CD Player will have Outputs typically in the 1V to 2V region per channel.
Consequently, the CD Player will appear to be 'shouting' in comparison to the Tuner.

Mr Tuner giving 150mV
150mV
Mr CD giving 1.5V
1.5V
Initial setup proceses:
If you have the CD Player plugged into Channel 1 and the Tuner into Channel 2,
with the front Volume Control on the PreAmplifier say at 12 O'Clock - when you switch between the CD and the Tuner then the volume levels will be totally different. The CD will be much louder than the Tuner.

The T90 Stack is cleverly designed to suppliment features of other PreAmplifiers - giving an input 'GAIN' control on each channel to adjust sensitivities.

You can remove the lid of any Baldwin HiFi PreAmplifier (there are no dangerous Voltages inside).

With a small slotted screwdriver you can rotate the input adjustment trimmers associated with the CD to 'turn the levels down' a little.
Switch between the Tuner and CD Player then the trimmers allow you to adjust the sensitivity of the CD Left and Right hand inputs to the same level as the Tuner.

The trimmers do not affect the quality of the sound throughput, colouration or equalisation at all - they just allow you to trim the levels of your signal sources to even up in volume when you switch between them.
Input Sensitivities:
Baldwin HiFi T90 Stack PreAmp has 8 LINE Inputs via the sets of Phono (RCA) Sockets on the rear + an inbuilt MM RIAA circuit on input 9.

A LINE Input allows source devices to be plugged in which have outputs varying from 100mVolt through to up to 2Volts @ 100kOhms Impedance.
So - in effect - you can plug in CD Players, Tuners, Tape Recorders, Computers, DAC units et al - All except Magnetic Cartridges in TurnTables which would produce a very weak low level sound. In this instance you need an additional Equalisation PreAmplifier known as an RIAA equaliser (see below).

If you have a Turntable with a Crystal Cartridge - then this will plug into a LINE input fine - albeit with a bit of additional distortion noise (a trait of Crystal Cartridges).

RIAA: If you have a Turntable with a MM or MC Cartridge - you will need an additional amplifier to make the very small signal out (less than 2mV up to 20mV) 'louder'.
The RIAA circuit also has additional inbuilt equalisation to electronically change the tones generated by the Cartrdge to make the Vinyl you are playing sound right.


Setup stage 2:
Once you have adjusted all your input sources and the levels are roughly equal then you now can adjust the meter sensitivies.

The T90 Stack has 2 sets of meter drives - one set for the Input monitoring and one set to monitor what the Power Amplifiers are doing.

The PreAmp Input Meter Adjusters
These just monitor the inputs.
The Power Amp Meter Adjusters
You will need to have the main
volume up for these to react.
The Active PreAmp Adjusters
DO NOT ADJUST THESE unless you talk to Paul.
Warranty:

The ReelAudio Custom Built Baldwin HiFi Units 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.

Machines left in the workshop for more than 6 Months and not collected will be disposed of as Storage Costs are high.

Any carriage costs are the responsibility of the Client

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
Founder: BaldwinHiFi.Co.UK
12 Tack Lee Road
Yapton
Arundel
West Sussex
BN18 0HB - UK - Great Britain

Direct EMAIL: neverfinished0@hotmail.com
EBay Customers: Please use this direct email with your questions - the Ebay email system is now amazingly unusuable
and history has shown that either one of us can get banned for asking or responding to technical questions.

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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