LaChapell Audio 503 User manual

1266 Park Road
Chanhassen, MN 55317
952-401-7700
suppor[email protected]
www.digitalaudio.com
LACHAPELL AUDIO 503 USER GUIDE
Version 1.1
August 2017

LACHAPELL AUDIO 503
SAFETY INSTRUCTIONS
TO REDUCE THE RISK OF ELECTRIC SHOCK, DO NOT REMOVE COVER. NO USER SERVICEABLE PARTS
INSIDE. CONTACT DIGITAL AUDIO LABS FOR SERVICING.
The lightning flash with arrowhead symbol, within an equilateral triangle, is intended to alert the user
to the presence of uninsulated and/or potentially dangerous voltage within the products enclosure
that may be of sufficient magnitude to constitute a risk of electric shock to persons.
The exclamation point within an equilateral triangle is intended to alert the user to the presence of
important operating and maintenance (servicing) instructions in the literature accompanying the
appliance.
IMPORTANT SAFETY INSTRUCTIONS
1. Read and understand this entire manual.
2. Keep this manual available for reference.
3. Heed all warnings and precautions in this manual and notices marked on the product.
4. Do not use this product near water or damp environments.
5. Refer all servicing to qualified service personnel. There are no user serviceable components inside
the product.
6. The product shall not be exposed to moisture. Do not touch the unit with wet hands. Do not handle
the unit or power cord when your hands are wet or damp.
7. The product should be connected to a power supply only of the type described in the operating
instructions or as marked on the product.
CARE
• From time to time you should wipe off the front and side panels and the cabinet with a dry soft
cloth. Do not use rough material, thinners, alcohol or other chemical solvents or cloths since this may
damage the finish or remove the panel lettering.
• The manufacturer cannot be held responsible for damages caused to persons, personal possessions,
or data due to an improper or missing ground connection.

LACHAPELL AUDIO 503 1
DIGITAL AUDIO LABS LIMITED WARRANTY
Digital Audio Labs warrants their products against defects in material and workmanship for a period of two years
from date of purchase. During this period, Digital Audio Labs will, at its option, repair the defective unit or replace
it with a new or rebuilt one.
The warranty does NOT cover:
• Damage due to abuse, misuse, or accident.
• Damage due to operation contrary to the instructions in the product instruction manual.
• Units on which the product serial number has been removed or altered.
• Units that have been serviced by unauthorized personnel.
All implied warranties, including warranties on merchantability and fitness, are limited in time to the length of
this warranty. Some states do not allow time limitations on implied warranties, so this limitation may not apply
to you. Digital Audio Labs’ liability is limited to the repair or replacement of its product. Digital Audio Labs shall
in no way be held liable for incidental or consequential damages resulting from the use of their product or
its software, including, without limitation, damages from loss of business profits, business interruption, loss of
business information or other pecuniary loss. Some states do not allow the exclusion or limitation of incidental or
consequential damages, so the above limitation or exclusion may not apply to you.
REPAIR POLICY
Please do not return the product without obtaining an RMA number first. Contact Digital Audio Labs at support@
digitalaudio.com to acquire an RMA number. Do not return the product to the place of purchase. Please write
the RMA number on the outside of the shipping carton. Any product sent to us without a valid RMA number will
be refused. Include the following with the product: a brief description of the problem, your name, return shipping
address, phone number and the RMA number. Do not include any accessories. DAL is not responsible for any
damage to or loss of the product during transit. We recommend that customers obtain a receipt and tracking
number for all packages shipped to us. Turnaround time on repairs is generally ten business days. If you live
outside of the United States, please contact your local distributor for warranty service.
Please return product to:
Digital Audio Labs
Attn: RMA Number
1266 Park Road
Chanhassen, MN 55317
USA
WARRANTY SERVICE
You will be required to pay the shipping charges when you ship your product to DAL. DAL will pay for return
shipping via UPS ground. We reserve the right to inspect any product that may be the subject of any warranty
claim before repair is carried out. For warranty service, we may require proof of the original date of purchase if
you have not registered your product with DAL. Final determination of warranty coverage lies solely with Digital
Audio Labs.
NON-WARRANTY SERVICE
If it is determined that the product does not meet the terms of our warranty, you will be billed for labor, materials,
return freight and insurance. There is a $80 USD minimum charge for materials and labor. Appropriate shipping
charges will be applied. We require payment in advance of repair by credit card; we accept Visa and Master
Card. In the event the charges are over the minimum charge, DAL will contact you and inform you of the cost of
the repair before any work is completed.

LACHAPELL AUDIO 503
CONTENTS
SAFETY INSTRUCTIONS.................................................................................................................................................................II
IMPORTANT SAFETY INSTRUCTIONS.............................................................................................................................II
CARE...........................................................................................................................................................................................II
DIGITAL AUDIO LABS LIMITED WARRANTY........................................................................................................................1
REPAIR POLICY.......................................................................................................................................................................1
WARRANTY SERVICE ...........................................................................................................................................................1
NON-WARRANTY SERVICE...............................................................................................................................................1
MODEL 503 .......................................................................................................................................................................................3
BEFORE YOU GET STARTED........................................................................................................................................................3
SAFETY PRECAUTIONS ........................................................................................................................................................3
503 CONTROLS ...............................................................................................................................................................................4
CONTROL DETAILS ..............................................................................................................................................................4
503 FREQUENCY RESPONSE.....................................................................................................................................................5
HPF - 50HZ.................................................................................................................................................................................5
HPF - 150HZ...............................................................................................................................................................................5
LPF - 5KHZ..................................................................................................................................................................................5
LPF - 10KHZ ...............................................................................................................................................................................5
LACHAPELL AUDIO 503 SPECIFICATIONS ..........................................................................................................................6
LACHAPELL AUDIO SUPPORT...................................................................................................................................................6

LACHAPELL AUDIO 503 3
MODEL 503
The LaChapell Audio 503 is a 3-band transformer-less EQ based on the EQ section of the 583E pre/EQ.
The 503 features additional cut/boost range of +/12dB, 2-position high-pass and 2-position low-pass
filters along with a gain trim stage of +/- 6dB.
BEFORE YOU GET STARTED
Stated below are a few areas that you must take the time to read before you install and use your 500
Series. You as the owner/user are responsible for completely understanding how to operate this device
safely and properly.
• UNPACKING: Inspect thoroughly. Although we take extreme care at final assembly and packing,
things can happen during transit. It is very important that you contact LaChapell Audio if there is
anything broken or damaged upon receipt of package. Included in every package should be:
(1) preliminary operating manual, (1) packet of mounting screws, (1) registration card. It is a good
idea for you to retain the packaging (box & foam case) in case there is a need to return the unit
for service or repair at a later date.
• SERVICE/REPAIR - WARNING: Only Digital Audio Labs personnel are to perform maintenance and
service activities.
SAFETY PRECAUTIONS
• Always provide adequate ventilation by allowing the top vents of your 500 series power supply
chassis to remain unobscured.
• Never position the power supply directly above other heat generating sources such as a power
amplifier.
• Always provide a source to ground (earth.) Never under any conditions should a power cord that
has the 3rd prong for ground missing or defeated be used with the power supply.
• Do not place the 503 in an area where there is a potential for fluids to fall, spill into or come in
contact with the 503. If you notice fluids or moisture present inside the 503 DO NOT turn power on!
Contact Digital Audio Labs for direction.

LACHAPELL AUDIO 503 4
503 CONTROLS
CONTROL DETAILS
• HIGH FREQUENCY SWEEP CONTROL: Fully variable sweep range; 2.5kHz to 20kHz.
Q value of 1 at +8dB.
• MID FREQUENCY SWEEP CONTROL: Fully variable sweep range; 325Hz to 5kHz.
Q value of 1 at +8dB.
• LOW FREQUENCY SWEEP CONTROL: Fully variable sweep range; 30Hz to 400kHz.
Q value of 1 at +8dB.
• HIGH-PASS FILTER (HP): 2-position HP filter provides 3dB cut at 150Hz or 50Hz.
• LOW-PASS FILTER (HP): 2-position HP filter provides 3dB cut at 5kHz or 10kHz.
• TRIM CONTROL: This is a transformer-less post-EQ gain stage providing 6dB of clean cutting or
boosting for the overall signal being processed. This control is post EQ In/Out control.
• FREQUENCY CUT/BOOST CONTROLS: Provides 12dB of cutting or boosting of selected frequency
from corresponding sweep control. A center detent is available on each band.
• EQ IN/OUT: This is a dual color LET toggle switch. Red will indicate the EQ settings have been by-
passed, green will indicates active EQ. The control does not effect the trim.
LaChapell
Audio
Model 503
3-Band EQ
+12-12
+6-6
+12-12
+12-12
400
25050
3k500
12k3k
160
30
5k
1.8k
325
20k
10k
2.2k
EQ OUT
50
150
.
EQ IN
Low
Mid
High
Trim
5k
10k
.
EQ IN/OUT
TOGGLE
HIGH BAND
CUT & BOOST
LOW-PASS
FILTER
TRIM
CONTROL
HIGH BAND
FREQ.
MID BAND
CUT & BOOST
MID BAND
FREQ.
LOW BAND
CUT & BOOST
LOW BAND
FREQ.
HIGH-PASS
FILTER

LACHAPELL AUDIO 503 5
503 FREQUENCY RESPONSE
HPF - 150HZ
LPF - 10KHZ
HPF - 50HZ
LPF - 5KHZ

LACHAPELL AUDIO 503 6
LACHAPELL AUDIO 503 SPECIFICATIONS
Noise Floor -90dB
THD+N 0.014%
Frequency Response 10Hz - 50kHz
Cut/Boost Range ± 12dB
Max Input >24dB
Input Impedance 48kohm
Input/Output Type Transformer-less
Output Impedance 50 ohm
Power Requirements 100ma
NOTE: Stated specifications are typical measurements but subject to change without notice due to individual traits unique to
each tube. All measurements taken while driving a 40kohm load and using a 1khz tone.
LACHAPELL AUDIO SUPPORT
Phone Support: 952-401-7700
Toll Free: 844-DAL-INFO
Email Support: suppor[email protected]
Website: www.digitalaudio.com/support
DIGITAL AUDIO LABS
1266 Park Rd
Chanhassen, MN 55317

® 2014, 2015 Digital Audio Labs. ™ & © 2017 Digital Audio Labs.
Patents pending.