Aesthetix Audio Io Owners Manual

							
 
 
 
 
 
 
 
 
 
Io 
PHONO STAGE 
 
 
 
OWNERS MANUAL 
 
 
 
 
 
 
 
Aesthetix Audio Corporation 
5220 Gabbert Rd., Suite A ♦ Moorpark, CA. 93021 
Phone: (805) 529-9901 
  
						

							
 
 
 
 
INTRODUCTION 
 
 
     Thank you for purchasing the Io Phono Stage.  It has been engineere\
d to deliver the highest 
attainable sound quality from your turntable.  Only the highest grade electronic components are 
used in the Io, including:  non-inductive wirewound resistors in the sig\
nal path; polystyrene, 
polypropylene, and Nichicon electrolytic power supply, bypass, and signa\
l capacitors; low noise 
matched vacuum tubes; glass epoxy dual mono circuit boards; 20 gauge steel chassis; custom 
wound high flux power transformers. 
 
PLACEMENT 
 
 
The Io main unit should be located away from possible sources of hum such as power cords, 
power transformers and the like.  It should not be located on top of its own power supply or any 
other heat source such as a power amplifier.  It must be kept well ventilated for proper operation.  
If it is positioned within an enclosed space then fans may be warranted.  All air vents must 
remain unobstructed.  The power supply is the main source of heat and should therefore be 
positioned for adequate ventilation and away from the main unit, if possible.  Placement of the 
power supply immediately below the main unit reduces tube life. 
 
 
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CONFIGURATION 
 
THE FOLLOWING PROCEDURES SHOULD ONLY BE ATTEMPTED 
WITH THE POWER CORD DISCONNECTED. 
 
INPUT IMPEDANCE: 
 
Note:  If 47K ohms is the desired input impedance, the unit comes factory configured for this 
setting.  The following instructions may be skipped. 
 
 
 
The input impedance of Io may be configured to virtually any useful value.  On the back panel of 
the main unit, locate the section labeled “INPUT IMPEDANCE”.  Two jumpers (and a spare) are 
supplied with Io, one for the left channel and one for the right.  Locat\
e the desired input 
impedance and its corresponding jumper position in the following table:  
 
IMPEDANCE    JUMPER POSITION
10K       10 
4.75K       9 
1K       8 
475       7 
243       6 
121       5 
75       4 
40.2       3 
20       2 
10       1 
 
Orient the supplied jumper vertically and insert onto protruding pins below the desired position 
number (use needle-nose pliers).  Do the same for the remaining channel.  If an intermediate not 
listed value of input impedance is desired, please contact the factory.  Virtually any value is \
easily attainable. 
 
The correct loading will be achieved when music has the right balance of dynamics, high 
frequency extension and lack of glare or bri ghtness.  Generally speaking, less loading (higher 
ohms) results in more high frequencies and more dynamics but can be too bright with some 
cartridges.  More loading (lower ohms) can reduce brightness but if overdone can result in 
reduced dynamics and a dull, lifeless quality.  Consult your dealer for loading recommendations 
on the cartridge(s) you are using.  One way is to start by setting the\
 Io’s impedance to 10 times 
that of the cartridge, then listening and making minor adjustments to achieve the right balance of 
dynamics, high frequency extension and lack of glare or brightness.  
 
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GAIN ADJUSTMENT: 
 
Important note:  Io with volume controls has no internal gain adjustment.  Use volume 
controls. 
 
1.  Ensure that the power cord is disconnected from the Io preamp. 
 
2.  To ensure proper capacitor discharge, wait a minimum of 20 minutes before removing top 
cover. 
 
Inside an Io main unit there are two circuit boards, one for the left channel and one \
for the right.  
Each of these circuit boards contains two jumper blocks, which are used for setting the gain.  
Please refer to figure 3 for block locations. 
 
A block adjusts the gain for one phase of the balanced signal.  To properly adjust the gain, both 
blocks for each channel must have the same jumper settings.  There are two jumpers per block. 
Both jumpers on each block, need to be positioned for the same attenuation amount. Therefore 
changing the preamp gain means 8 jumpers on 4 blocks must be set. 
 
There are five possible gain settings which ar e represented as ATT 1, ATT 2, ATT 3, ATT 4 and 
ATT 5.  The chart in figure 2 indicates each of these settings as a deci\
bel (dB) range. 
 
 
  
 
 
 
Jumper 
Attenuation 
Amount 
Overall 
Gain 
ATT 1 0dB ~80dB 
ATT 2 -6dB ~74dB 
ATT 3 -12dB ~68dB 
ATT 4 -18dB ~62dB 
ATT 5 -30dB ~50dB 
    
  Figure 1: Block Identity  Figure 2: Jumper Settings 
 
 
On each circuit board, only ATT 2, ATT 3 and ATT4 are marked, and only on one of the blocks. 
Therefore please refer to the ‘block’ diagram above for the complete ATT positions.  
 
Important Note: If using ATT 5, tubes V5 and V6 must be removed. 
 
3.  Set all 8 jumpers for the desired gain, according to the information above and in figures 1-3. 
 
4.  Replace top cover and screws. 
 
5. Test unit. 
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Figure 3: Io Preamp Circuit board (1 of 2) 
 
 
 
 
 
  
						

							
 
 
 
 
CONNECTIONS 
 
 
 
CAUTION: It is vitally important that you do NOT disconnect the umbilical cables (between 
the power supply and main unit) for AT LEAST 15 MINUTES AFTER TURNING OFF THE 
MAIN POWER SWITCH and removing the AC cord from the power supply. 
 
Note:  Never connect power supplys power cord to a wall outlet while umbilical cables are 
disconnected.   
 
A.  Connect male end of one of the supplied umbilical cables to a power output jack on the 
power supply.  This is a keyed connector so proper alignment is necessary for correct pin 
connection.   
 
Important note:  Io umbilical cables are 19 pi n (for single supply operation) or 21 pin (for 
dual supply operation).  Do not use umbilical cables with fewer pins than required.  No 
damage will occur, but certain tubes will not receive heater supply voltage\
. 
 
B.  Connect female end of the same umbilical cable to a male receptacle on the main unit. 
 
C.  Connect male end of the other supplied umbilical cable to the remaining power output  jack on the power supply.   
 
D.  Connect female end of the same umbilical cable to the remaining male receptacle on the main unit. 
 
E.  Connect turntable to the Io using either RCA or XLR connectors. 
 
F.  Connect Io to either a preamp line level input or a linestage input using the XLR or RCA connections. 
 
G.  Because the Io contains no turn-on mute circuitry the following procedure is recommended anytime the Io is initially turned on: 
 
Ensure that either the power amplifier is off or the linestage (preamp) is selected to an input different from the one Io is connected to.  This will prevent any turn-on artifacts from 
reaching loudspeakers. 
 
H.  Connect power cord of the power supply to an unswitched grounded wal\
l outlet.  It is not recommended to use any sort of line conditioner with the Io.  Any failure cause\
d by such a 
device will not be covered under warranty. 
  6 
						

							
 
 
 
 
 
OPERATION 
 
*Ensure linestage/preamp and/or power amp are properly muted to prevent possible damage 
to speakers. 
 
A.  Turn power on. 
 
B.  Wait at least fifteen minutes for power supplies to fully stabilize before unmuting preamp. 
 
C.  Begin playing record. 
 
D.  If the optional second input is installed, before switching inputs mute the preamp. 
 
E.  Always unmute linestage with volume fully counter-clockwise and then slowly increase the volume until desired listening level is achieved. 
 
F.  Mute linestage before lifting stylus from record.  This will prevent any unwanted noises from reaching the speakers. 
 
G.  Before turning Io off, ensures that preamp/linestage and/or power amp are properly muted. 
 
H.  Turn off Io. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  7 
						

							
 
 
 
 
TECHNICAL DESCRIPTION 
 
 
NOTE:  The following is a detailed technical description of the circuitry employed in the Io. 
It is intended for technically inclined readers for informational purposes only. 
 
     The Io comprises two separate units, the phono stage itself and the power supply un\
it.  The 
units are connected together via two detachable umbilical cords.   
 
     The phono stage contains three main amplification sections and an output buffer section.  
The first section is a high gain, low noise, zero feedback single ended \
amplifier composed of 
two low-noise 12AX7 vacuum tubes.  This then feeds a high gain, low noise differential 
amplifier (two 12AX7 vacuum tubes) which amplifies the signal and produces a 
complementary minus phase signal.  Thus, the unit is balanced from the second amplification 
section through the output.  The signal is then applied to the third amplification section which 
is nearly identical to the second.  It also contains two 12AX7 vacuum tubes.  The filter is next 
in the signal path, a purely passive design with the highest grade capac\
itors and non-inductive 
wirewound resistors throughout.  Lastly, the signal  is buffered and sent to the output jacks in 
balanced form.  Each separate amplification section has its own power supply filtering 
network and regulated heater supply to isolate  the individual sections and prevent them from 
interacting. 
 
     The Power Supply has two main sections, the heater power supplies and the primary plus 
and minus power supplies.  The heart of the heater supply  
is its massive, low flux, 210 volt-amp power transformer which has no less than fourteen 
separate secondary windings that are individua lly regulated and supply both the power supply 
and main unit tubes.  The primary high voltage supply is composed of a similarly massive 170 
volt-amp transformer which feeds a common-mode choke input filtering network and then 
high current vacuum tube regulators (one EL34/6CA7, three 12AX7 tubes per regulator). 
Each regulator is capable of supplying 600 volts at 100mA.  There are two such regulators in 
the power supply.
 
 
Specifications 
     (117v only) 
 
Fuses:  
External heater fuse     2 amp slow blow for 117V units 
External high voltage fuse  2 amp slow blow for 117V units 
External heater fuse     1 amp slow blow for 230V units 
External high voltage fuse  1 amp slow blow for 230V units 
 
 
 
  8 
						

							
 
 
 
 
Io phono stage vacuum tube locations
Back of left channel circuit boardBack of right channel circuit board
Front of left channel circuit board Front of right channel circuit board
XLRXLR
V8V4
V3
V5
V6 V7
Phono 2.3
V2
V1
First gain stage
12AX7LP or 12AX7LP or
E83CCSE83CCS E83CCS
Volume
Control
(Optional)
Second gain stage V3/V4 12AX7 V3/V4 12AX7
or E83CCS or E83CCS
Third gain stage V5/V6 - 12AX7 V5/V6 - 12AX7
or E83CCS or E83CCS
6922
6SN7
Output stage
XLR
XLR
V8V4
V3
V5
V6 V7
V2
V1
First gain stage
Phono 2.3
Volume
Control
(Optional)
Second gain stage
Third gain stage
6922
6SN7
Output stage
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
V1 and V2   =  12AX7 or E83CCS 
 
V3 – V6    =  12AX7 or E83CCS 
 
V7   = 6922 
 
V8   = 6SN7 
 
 
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90 DAY LIMITED WARRANTY TERMS AND CONDITIONS 
(3 Year optional extended service contract) 
 
1.  Aesthetix warrants the product designated herein to be free of manufacturing defects in material and 
workmanship, subject to the conditions herein set forth, for a period of 90 days from the date of purchase by the 
original purchaser. If the purchaser registers the unit with Aesthetix by mailing in the warranty card, together 
with a copy of the bill of sale, within 14 days of the date of purchase, said purchaser will be registered for an 
extended service contract. The extended service contract extends the 90 days to a period of 3 years from the date 
of purchase by the original purchaser or no later than 4 years from the date of shipment to the authorized 
Aesthetix dealer, whichever comes first.  The warra nty period for factory tubes does not get extended and 
therefore remains at 90 days. 
 
2. CONDITIONS 
  This warranty is subject to the following cond itions and limitations.  The warranty is void and 
inapplicable if the product has been us ed or handled other than in accordance  with the instructions in the owners 
manual, abused or misused, damaged by  accident or neglect or in being transported, or the defect is due to the 
product being repaired or tampered with or modified  by anyone other than Aesthetix. The product must be 
packed and returned to Aesthetix by the customer at  his or her sole expense.  A returned product must be 
accompanied by a written description of  the defect and a photocopy of the original purchase receipt.  This 
receipt must clearly list model and seri al number, the date of purchase,  the name and address of the purchaser 
and authorized dealer and the purchase price.  Aesthetix reserves the right to modify the design of any product 
without obligation to purchasers of previously manufactured products and to change the prices or specifications 
of any product without notice or obligation to any person. 
 
3. REMEDY 
  In the event the above product fails to meet the wa rranty, and the above conditions have been met, the 
purchasers sole remedy under the limited warranty shall be  to return the product to Aesthetix where the defect 
will be rectified without charge for parts or labor. 
 
4.  LIMITED TO ORIGINAL PURCHASER 
  This warranty is for the sole benefit of the original purchaser of the covered product and shall not be 
transferred to a  subsequent purchaser of the product. 
 
5.  DURATION OF WARRANTY 
  This warranty expires 90 days after the date of or iginal purchase.  If Aesthetix receives the warranty 
registration card, this period is extended to the third anniversary of the date of purchase or no later that the 
fourth anniversary of the shipment to the authorized Aesthetix dealer, whichever comes first.  The warranty 
period for factory tubes does not get extended and therefore remains at 90 days. 
 
6.   MISCELLANEOUS 
  ANY IMPLIED WARRANTIES RELATING TO  THE ABOVE PRODUCT SHALL BE LIMITED 
TO THE DURATION OF THIS WARRANTY.  THE WARRANTY DOES NOT EXTEND TO ANY  
INCIDENTAL OR CONSEQUENTIAL COSTS OR DAMAGE S TO THE PURCHASER.  Some states do not 
allow limitations on how long an implied warranty lasts or an exclusion or limitation  of incidental or 
consequential damages, so the above limitations or exclus ions may not apply to you.  This Warranty gives you 
specific legal rights, and you may also have other rights which vary from state to state. 
 
7.    WARRANTY  OUTSIDE THE USA 
  Aesthetix has formal di stribution in many of the countries of the free world, in each country the 
Aesthetix importer has contractually accepted the re sponsibility for product warranty.  Warranty should 
normally be obtained from the importing dealer or distributor from whom you obtain your product.
 
Rev 2.8 4-8-14 
10