Dada Electronics Australia®
is the Asia-Pacific agent and distributor for
Dada Electronics Europe, located in Belgium,
also represented by
Dada Electronics North America.
We have
has been providing vintage hi-fi services and repairs since 2005,
with hundreds of satisfied customers in
Australia,
New Zealand,
Japan,
Indonesia,
Malaysia,
Singapore,
and elsewhere in our region, as far away as Vladivostock.
We have 50 years' experience as Quad listeners;
30 years' experience as happy Quad owners;
several decades of performing classical music at the highest level;
and a lifetime interest in hi-fi and electronics,
including stints in the music and recording industries.
We specialize in restoring and improving the musical performance of hi-fi equipment.
Dada Electronics Australia is now expanding into repairs of
other hifi brands,
valve guitar amplifiers,
and certain Tektronix test equipment.
Quad repair in Australasia is only officially supported via the warranty agent during the 12-month warranty period.
We specialize in Quad equipment of all vintages back to Quad's own beginnings in 1936,
in accordance with Quad's own factory policy in the UK.
We started down this road merely to fix our own several generations of Quads,
being unable to find repairers.
We are also experienced in a number of other well-known brands
including Leak, Radford, McIntosh, Marantz, and HH Scott.
We also specialize in valve FM tuners.
We offer
Dada Electronics Europe's
standard, fixed-price servicing for many valve and solid-state Quad, Leak, and Radford hi-fi units.
These services include everything required to renovate and renew vintage hi-fi
and make it ready for another decade of pleasure.
We have for many years also offered fixed-price servicing
for Quad valve amplifiers, preamplifiers, and tuners,
for several other vintage brands shown below,
and for almost any valve AM or FM tuner,
subject to availability of service information.
Our fixed-price services are designed to cover about 90%
of the faults that normally arise over time, such as
increased noise levels or distortion,
noisy controls,
poor channel separation,
woolly bass,
etc.
This has been borne out over many years of experience and hundreds of units.
Any repairs still required after completing the service are charged at T&M rates by prior agreeement.
Service prices do not include transistors, valves/vacuum tubes, lamps, or other components required to correct remaining faults.
Servicing typically includes:
Replacement of electrolytic capacitors, which dry out over a period of decades, and lose function.
Testing and condition report on all valves.
Upgrade of any op-amps.
Upgrade of audio IC switching chips if present.
Replacement of other critical components, including in some cases all power supply components.
Addition of RCA input sockets and replacement of speaker posts on early Quad 405 amplifiers.
Realignment of class A or B power amplifiers where necessary.
Laboratory testing to ensure factory specification is met.
A listening test conducted over several hours to 'burn-in' new components and assure final quality.
We will also recommend sources for valves and cables as required. We do not supply these ourselves in most cases.
Leak released an astonishing number of valve preamps over quite a short period of about a decade,
often having four models in production at the same time (Point One/Varislope and mono/stereo).
See the listbox for chronology.
They suffer from enormous output impedance
due to not having a final buffer stage,
which severely limits the length of the umbilical interconnect cable;
and from the tape-out being taken off after the tone controls and filters,
and the balance control where present,
which makes it basically useless.
The design before the high-impedance filter stage and balance control is elegant,
and economical in using the same gain stage for everything from 5mV phono to 2V tuners:
however this inevitably compromises the distortion performance of the phono input.
Not all of the Leak preamps interconnect with all the valve power amplifiers,
due to differing umbilical socket connections.
We can advise on or modify the umbilical cable,
which Leak must have provided in different versions, mutually incompatible.
See the following table.
Leak Umbilical Cable pinouts
Unit
1
2
3
4
5
6
7
8
RC/PA,
RC/PA/U,
Varislope
E
HT
Heater
Heater
Output
Point One
Output
E
HT
Heater
Heater
HT
E
Varislope II
Output
HT
Heater
Heater
HT
E
Varislope III,
Varislope III Series N,
Point One Plus,
Varislope Mono
Output
Heater
Heater
HT
E
Point One Stereo,
Varislope Stereo,
Varislope 2 Stereo
Output L
Heater
Heater
HT
Output R
E
Point One amplifier Type 15,
Point One amplifier 25W
No umbilical socket, only a meter socket
TL/12,
TL/25,
TL/25A,
TL/10
E
HT
Heater
Heater
HT
E
Input
TL/12 Plus,
TL/25 Plus,
Tl/50 Plus
E
HT
Heater
Heater
E
Input
Stereo 20,
Stereo 50,
Stereo 60
E
Input R
HT
Heater
Heater
E
Input L
Source: published Leak schematics. No responsibility is taken for any errors or omissions.
Quad preamps
Quad 22s and 33s often require replacement of panel lamps, not included in the service but available for a small fee.
We can adjust your Quad 22 Phono adapter can, 33, 34, 44, or 66pre to match your phono cartridge exactly if required, for no extra charge.
Radford preamps
We have serviced all the Radford preamps from the valve SC22 to the solid-state SC24 and ZD-22,
the latter being also built into the HD and ZD power amplifier series.
They are all remarkable, especially the SC22, which however does exhibit
a not quite flat frequency response 20-20kHz (±0.3dB) due to the tone control section design,
and not startlingly accurate RIAA phono equalization.
The umbilical cable used between the SC22 and the MA- and STA- power amplifiers is wired as shown in the table below.
It is wired 1-1, 2-2, 3-3, 4-4, 5-5, 6-6, 7-7, 8-8.
Please note that this is NOT COMPATIBLE with the majority of Leak umbilical cables,
from the points of view of both the pinouts and the current capacity of each wire.
Radford Umbilical Cable pinouts
Unit
1
2
3
4
5
6
7
8
SC22
Heater
E via R42 56R
AC
AC
AC=3, switched
HT
Heater
SC22P
No socket: this unit is self-powered.
MA series
Heater
E
AC=4
AC
AC
AC=4, switched
HT
Heater
STA series
Heater
E
AC=4
AC
AC
AC=4, switched
HT
Heater
Source: published Radford schematics. No responsibility is taken for any errors or omissions.
The Quad II is one of the most sought-after classic amplifiers of the valve era.
We have serviced many of these and can also replace the outmoded mains input sockets with IEC sockets.
Quad 50E
We have serviced this fairly rare model, and we can adjust the outputs
to practically any impedance level including multiple different impedances,
suitable for bi-wiring.
If you buy these units make sure the irreplaceable input and output plugs are included in the sale.
The optional 600Ω input transformer is not required unless you have some antique 600Ω impedance sources,
and in any case suitable substitutes are still available.
Quad 303
The Quad 303 is especially noteworthy as being an absolute bargain at present,
selling for only a few hundreds of dollars.
Some audiophiles have rated this amplifier in the $1500 value class.
We have restored hundreds of 303s and we have now added a complete rebuild option
beyond the standard service, where we also replace every single PCB-level component,
to assure correct and trouble-free running for decades.
We can adjust the sensitivity of 405s, 606s, 707s, and 909s at no extra charge.
Many users find these too sensitive: a 2x or 3x gain reduction makes them more usable.
The selected Berndt Ludwig 405 modifications we perform are sufficient to more or less transform a 405-1 into a 405-2.
Harman Kardon
The Harman Kardon Citation series is very under-appreciated.
We recently serviced a Citation 12 whose performance was quite stunning,
far in advance of its specifications.
The channel separation, bandwidth, and signal-to-noise ratio are exceptional,
and the total harmonic distortion was far below the modest 0.1% specified.
Leak TL, TL Plus, and Stereo series
We service all Leak valve amplifiers at a fixed price per channel.
We specialize in undoing prior modifications by well-meaning amateurs, or in some cases professionals,
and restoring them to factory condition.
McIntosh
We service all McIntosh valve amplifiers.
Radford MA, STA, SPA, HD, ZD series
We service all Radford amplifiers, both valve and solid-state.
Mullard
The Mullard 5/10 and 5/20 amplifier circuits formed the basis (in many cases, the entirety) of many
British and Australian amplifiers in the 1950s,
notably
models by Dynaco and Marantz,
the Armstrong 220,
the Avantic DL-75 by Beam Echo (presently being remanufactured),
and the Brunswick (Melbourne)-based Servo Mechanism Co. MIL amplifiers and preamps.
Cosmos
The Cosmos stereo (10W/channel) integrated valve amplifier was produced in Japan in the early 1960s.
It uses an unusual valve complement of 1 x 12AX7 and 4 x ECL82s,
with the phase splitters implemented in the triodes of the ECL82s,
and a passive tone control section.
The Cosmos brand has been erroneously attributed to Encel Stereo, Melbourne,
who no doubt retailed it,
but were never a manufacturer, or even a re-brander, to our knowledge over 50+ years.
Other brands
Service of other-brand valve and solid state amplifiers is subject to availability of service material and a $90 inspection fee.
We specialize in RF and IF alignment and MPX calibration of valve and solid-state AM and FM tuners by
Quad,
Leak,
Radford,
Sugden,
Dynaco,
H.H. Scott,
Fisher,
McIntosh,
Marantz,
and other fine manufacturers.
We can evaluate the alignment and calibration of your tuner using our B&K, Sound Technology, and Tektronix test equipment without even removing the cover.
Quad HR1 and /R
These exceedingly rare units (fewer than 1000 /R units built in 1954-5 only)
were low-sensitivity high-fidelity AM tuners.
The /R had 3 preset stations (BBC Home, Light, and Third Programmes),
plus a phono feed-through connection.
The even rarer HR1 made 'no attempt at sensitivity'
and was designed to listen to nearby BBC transmitters only.
They were both connected directly to a Quad I or II power amplifier at 20mV level.
Acoustical A.M. Tuner ('half-moon')
This unit is part of the Quad II/22 setup with the same power requirements.
It is an audiophile-grade AM tuner with two bands, LW and MW, and two switchable bandwidths,
'tune' (7KHz) and 'wideband' (12KHz).
This rare early version is reputed to be the best-sounding of all Quad AM tuners.
The tuning dial is calibrated in metres of wavelength rather than frequency in KHz,
increasing from left to right,
so, entertainingly, the lower-frequency stations are to the right and higher-frequency ones to the left.
It uses an averaging detector, unlike the subsequent Quad AM tuners which use an envelope detector.
Quad AM1 Tuner (European/Export)
This unit is part of the Quad II/22 setup with the same power requirements.
It is an audiophile-grade AM tuner with several bands and switchable bandwidths.
European models had LW, MW, and SW bands;
export models had MW, SW1, and SW2 bands.
Both models had three selectable bandwidths:
'narrow' for tuning;
'filter' which provides a 10KHz notch filter which needs to be retuned to 9KHz
since AM frequencies were reallocated to 9KHz spacing in the 1970s;
'wide' providing a 12KHz wideband unfiltered output,
which sadly is more than double what any AM station broadcasts these days.
Quad FM
The correct name for this is 'the FM tuner', although it is often known as the FM1.
This is part of the Quad II/22 setup, needing to be powered by the 22 control unit or a separate 330VDC supply.
When well-aligned, it is a very serious audiophile contender among valve FM tuners.
There are four or five circuit variations, depending on serial number, including valve changes.
The original factory 'bird-cage' decoder is now of historical interest only,
and should generally be replaced with a modern unit.
However we can certainly align and renovate this original MPX unit, which will substantially improve the sound.
Quad FM2
This is essentially an 'FM tuner' in an AM3-sized case to match the 33 preamp,
with an independent power supply,
an internal stereo decoder,
and with somewhat better stereo performance than the 'FM tuner' due to minor circuit tweaks
Not to be confused with the later solid-state FM3 which superceded the FM2: see below.
Although the FM3 is a most competent performer, many audiophiles and collectors prefer the FM2,
especially when fitted with with a modern stereo decoder.
We can replace the FM2 decoder with a much better-performing modern unit.
Quad AM3
This is essentially an AM1 in an FM2-sized case with an independent power supply.
Like its predecessor, it is an audiophile-grade AM tuner with LW, MW, and SW bands and switchable bandwidths.
This was Quad's last valve tuner and also their last AM tuner.
Only 2000 were made,
so they are now much sought-after,
changing hands for four-figure (AUD) prices.
The five-figure serial numbers are accounted for by the fact that they run on from those of the AM2.
Quad FM3
This is the solid-state replacement for the FM2 above,
fitting into the same case as the 33 preamp and looking almost identical to the FM2 from the front,
except that the indicator lights are in the reverse positions.
There are three distinct versions: serial nos. 1-5884, 5885-9999, and 10,000 upwards.
To our ears the early FM3 before serial number 5885 sounds better than the later one, although it is more of a servicing headache:
the MC1305P decoder chip used early in the production run has seven adjustments to the two required by the MC1310P used subsequently.
Quad FM4
The FM4 tuner matches the 34 and 44 preamps and is a superb piece of work,
with 7-preset station memory,
and a laid-back sound to die for.
We can now supply and fit a new CPU made by Quad for this tuner,
which not only allows for 14 pre-set stations
but also eliminates the battery.
We can also supply and fit a factory modification for early models with long-term frequency drift.
Quad FM66
The FM66 and subsequent FM77 and FM99 Quad tuners are substantially similar to the FM4,
but with a revised RF section
and remote control.
Dynaco
The legendary Dynaco FM-3 was one of the best-sounding valve tuners of the era.
They were produced in enormous numbers, largely as kits.
After all this time an FM-3 will certainly need alignment,
and possibly renovation,
including coupling capacitor upgrades and PEC filter correction.
We have serviced this model and can correct the de-emphasis to 50μS for UK/European/Australia/New Zealand broadcast conditions.
H.H. Scott
H.H. Scott made some of the finest FM tuners and MPX units of the valve era,
including the 310, 314, 330, and 350 series, and the 335 MPX unit.
We have serviced all these models and can correct the de-emphasis to 50μS for Australia/New Zealand broadcast conditions.
Leak Troughline
These are among the most sought-after of all British valve tuners,
with exceptionally stable tuning due to three separate design elements;
two stages of limiting;
and quite remarkable sound.
The original factory stereo decoder is by now of historical interest only,
although we can certainly renovate and align it if required,
but generally we take great pleasure in replacing it with a modern unit.
Leak Stereofetic:
These are not among the most sought-after of all British tuners,
for reasons which escape us.
They have superb technical specifications, and audio performance quite similar to the Troughline series.
McIntosh
McIntosh made excellent valve tuners,
notably the MR66, MR67, MR71, and MAC1700 series,
which we have serviced,
including the MR66's outboard MA-6 MPX decoder.
Marantz
We have serviced the legendary Marantz 10B, and were also once proud owners of a 104.
Radford
The Radford FMT1/2/3 tuners were built to complement the SC22 (valve) and SC24 (solid state) preamps.
The FMT1 is a valve design using 1xECC85 in the RF and mixer stage, 3xEF89 in the IF strip, 1xEF80 as the limiter, an EM84 tuning indicator valve, a ratio detector, and an optional muting circuit.
No stereo decoder was supplied but a modern one can easily be fitted.
The FMT2 and FMT3 are solid state designs, again with ratio detectors, and with a quite nice stereo decoder fitted as an optional extra.
We can fit a modern IC-based stereo decoder to any of these models.
Other brands
We have also serviced tuners by Harmon-Kardon, Luxman, Pioneer, Sansui, Sony ES, etc.,
and in general can service and align almost any valve-based tuner, subject to availability of service information.
The stereo MPX unit we supply is based on the LM4500 IC used in the Quad FM4 and many other quality tuners.
Quad FM3s often require replacement of panel lamps, not included in the service but available for a small charge.
We offer the CD player services mentioned below.
A grinding noise when moving the tray in and out
indicates the need for tray alignment and a new pinion wheel.
Condition report
Sometimes you just want to know whether something is working, and how well, to help you decide whether to service, sell, etc.
We offer a condition report service:
an evaluation and written report on the current performance of any pre-amplifier, amplifier, active crossover, or tuner, for your information.
We perform a visual examination, graduated power-up, and measure as follows:
Preamplifiers
THD, IMD, bandwidth, RIAA accuracy, output level, all inputs and all outputs.
Power amplifiers
THD, IMD, bandwidth, stability, total power (up to 200W only).
Active crossovers
Gain, THD, IMD, crossover point(s), output level.
Tuners
RF sensitivity, quieting, THD, IMD, IF and audio bandwidth, FM de-emphasis accuracy, stereo channel separation.
This service can be done while you wait and costs $A30 per functional unit,
i.e. $A60 for integrated amplifiers (preamp+amp)
or $A90 for receivers (preamp+tuner+amp).
Site visits
For large installations such as recording studios we can also do a site visit,
to check all your channels of all your gear.
Of the services listed, only the standard THD, noise, bandwidth, and power tests are portable.
Price on application, including travel time in both directions.
We supply do-it-yourself service kits as below.
$ASK us about kits for Quad/Leak/Radford valve units and tuners: see Contacts below.
Each kit consists of
a set of PSU capacitors,
other electrolytic capacitors,
and other capacitors, resistors and diodes as required.
Complete instructions are provided,
and support via email is available during business hours to a reasonable extent.
You will need
forceps or pliers,
screwdrivers etc.,
a temperature-controlled soldering iron,
leaded solder,
desoldering wick or a desoldering pump,
a multimeter,
and reasonable proficiency in soldering and desoldering.
Prior experience in electronics is preferable if not essential.
A large range of spare parts is available at the Dada Electronics Europe Webshop.
The following spare parts are available here for immediate purchase from local stock.
A full set of Quad 303/33/FM3 cables comprises:
one power cable
two power interconnects: 33 to 303, and 33 to FM3
one 303/33 signal interconnect
one 33/FM3 signal interconnect.
The AM3 has its own captive cables,
and incidentally another 2-pin power outlet.
All cables above are supplied in 2-metre lengths.
Other lengths are available but we recommend two metres as the minimum:
you can have them too short but you can never have them too long.
We recommend
Flashback Sales UK
for other Quad and Leak cables,
especially those involving RCA or XLR plugs.
Our
power amplifier kits and
capacitor sets use Kemet BHC PSU capacitors with 28,000 hour rated lifetimes.
A large number of plastic parts for early Quad preamps, amplifiers, and tuners are now available for on-demand 3D-printing
at our Shapeways store.
These include:
a full selection of knobs, bezels, and other pieces for Quad 2, 3, and 4 series.
Quad II capacitor mount platform, feet
Quad 22 balance control & peg
Quad 303 PCB retaining clips
Quad 33 balance control mechanism, all buttons including CD/DVD/DAC/TV/blank, rear panel & flaps
Quad AM2/AM3 waveband & filter selector levers
Quad FM3 tuning needle, station indicators, rear panel, voltage selector panel
Due to the limitations of the 3D printing process,
these parts are very similar to, but not identical with, the originals.
Colour matching is not exact.
Redundant numbers have been removed from some knobs.
Separation, removal of knockouts, and minor trimming may be required.
6mm M3 hex head grubscrews are required for most shaft-mounting controls.
A 1.5mm Allen key is required to fit all parts having grubscrews.
A 1/4" 2BA screw is required for the Quad II foot mount,
available from us or several suppliers of British fasteners.
Replacement PCB boards for Quad 303 and 405 by Dada Engineering
are available
at the Dada Electronics Europe Webshop.
These are manufactured to the highest standards and follow the latest issued Quad designs.
The 303 boards provide options for adjusting the sensitivity to either 500mV (standard), 1V, or 1.5V.
Unit
PCB complement
303
2 x amplifier boards, 1 x PSU board
405
2 x amplifier boards
Prices shown are per single board.
These prices fluctuate with the AUD/EU exchange rate.
We provide a fitting service for Dada Engineering PCBs at $A30 per board including full testing,
or a full inspection, test, and alignment service at $A60 after you've fitted your boards but before first power-up.
ZD-985 Desoldering Station
The ZD-985 desoldering station is widely used and excellent value.
However many users have mistakenly bought new guns for these when the vacuum goes
low, only to find that the problem wasn't the gun, it was the vacuum pump.
Dada Electronics is the only known retailer of the vital vacuum pump diaphragms,
which you can blow out by misusing the gun, e.g. blocking the inlet and operating the vacuum trigger.
Replacement diaphragms are available at low cost in sets of 2, including zip-ties.
We can replace screens and batteries in any model iPad, iPhone, or iPod.
Same day service.
We do not require your unlock code.
Test when you collect.
Booking and 50% deposit required.
Too many models to list here, please ask.
We can undertake repair and renovation of any valve-based
Fender,
Gibson,
Gretsch,
or Eminar
guitar amplifier at T&M.
We may be able to service other brands, subject to availability of service information.
We do not service solid-state guitar amplifiers.
We can also supply and fit the TBX-1 and Active Mid-boost controls for Fender Stratocasters,
and perform electrical repairs inside electric guitars.
After various entertaining incidents in our laboratory,
we can now undertake repair of
Tektronix TM500 mainframes and a number of plugin units.
Repairs are charged at T&M.
Please ask us about other Tektronix equipment not listed here,
but note that we do not service oscilloscopes of any kind, although we can service
certain 7000-series plugin units as shown below.
We can also perform alignments and Brian Beezley's modifications for
Sound Technology ST-1000A units, including the low-distortion oscillator modification,
the level offset to balance mono and stereo modes on the meter.
We can also fit the 400Hz oscillator and external rear input BNC jack options if absent.
The AWA A56010 Voltohmyst is probably the most commonly found VTVM in Australia.
The A56010 is based on the RCA WV-87A, modified for 240VAC and other local conditions,
with a locally designed cabinet and front panel.
They were made in tens of thousands by Amalgamated Wireless Australia, and very widely used by local repairmen, radio & TV technicians,
etc., in the period 1953–about 1970 when DVMs came into use.
They are still much sought after, as there is still really no replacement
for a high-impedance (10MΩ) analogue voltmeter that can measure to ±1500VDC,
4200VAC P-P, and with a centre-zero facility, the last feature being invaluable in tuner alignments.
We can perform a pretty precise DC+, DC-, and AC alignment of this unit.
We also offer a small regulated 1.5VDC PSU unit to replace the D cell battery used for resistance measurements.
We can also fit an illuminated mains switch and an internal AC fuse, both required under modern codes.
Replacement probes are also available, including a 1MΩ DC probe.
Please contact us for details.
Our workbench
Our highly equipped workbench consists of
Tektronix™,
Sound Technology™,
EMC™,
and B&K™
test equipment for
function and signal generation;
THD and IMD distortion analysis and measurement;
noise-floor and bandwidth measurement;
spectrum analysis;
AM and FM tuner alignment;
valve testing;
transistor curve tracing;
and power supply simulation and testing.
We can handle both 240VAC and 110VAC equipment.
Procedure
You can purchase online here via our PayPal™ shopping cart.
For servicing:
Decide what you want.
Ring or contact us as below to discuss if necessary.
Send your item(s) to us, well packed, with a covering letter detailing any known faults, and providing a return address, phone number, and email address for PayPal billing.
We will confirm arrival and progress of the work, and raise any issues with you as necessary.
We will complete the service and then bill you via PayPal.
When you pay we will re-pack your item(s), reusing your own packing, and send them back to you.
We will enter the Australia Post tracking number on your payment at PayPal: they will send you an email confirming shipping and providing this number.
12 month warranty on all new parts and labour, valves excluded.
Payment is due on invoice, which we will render via PayPal when service is complete, or in some cases to fund parts.
Please allow 1-2 weeks for delivery of online purchases to allow for items out of stock.
Purchaser pays freight both ways for services and warranty claims.
Current T&M rate is $A60/hour.
We charge a fee for preparing quotations or 'lifting the lid' on equipment not listed here.
We reserve the right to charge an inspection fee for frivolous warranty claims.
Repairer's lien applies after 30 days under the Sale of Goods Act 1959, State of Victoria.
Goods unclaimed and unpaid for may be sold at public auction to recover costs, with credit balance if any refunded to owner.
Storage charges may apply from two weeks after invoice at our discretion.
Except as expressly provided by the laws of the State of Victoria and the Commonwealth of Australia
Dada Electronics Australia accepts NO LIABILITY whether consequential or otherwise arising out of its work.
Electronic equipment contains dangerous voltages, and owners and users are expected to exercise all due and necessary care and caution and use their own judgment when operating these devices.
Items placed with Dada Electronics Australia for repair or review are
covered for insurance purposes by a house contents policy only,
and no other liability against loss is expressed or implied.
Prices shown do not include GST, which is charged at 10% to Australian customers.
