Construction difficulty: The PCB is easy to construct but the full modification is complex. An oscilloscope is required for calibration.
A single DN34 BBD PCB can replace one channel of the DN-34 saving the need for eight working SAD512D chips.
The DN-34 Analogue Time Processor effect was made by Klark Teknik™ in the late 1970s. It features two channels of analogue delay each capable of creating a delay from around 1mS to around 27mS. The delay time could be controlled from a front panel pot, an internal LFO with sine, triangle and square waveforms, and an external control voltage (CV). The two delays could be operated in series to give one longer delay or in parallel to create interesting effects such as through zero flanging. What was particularly good about the DN-34 was the very good sound quality available from the unit. Most BBD devices tend to be noisy and have limited bandwidth but the DN-34 excelled in both these areas.
Each delay channel was made from eight SAD512D bucket brigade delay (BBD) chips. These devices are very difficult to source today and when you can get them they can be very expensive. This Oakley Sound module is designed to replace one channel of the DN-34 which replaces eight of these ultra rare SAD512D chips and their ancillary circuitry with near identical performance. It is, of course, possible to use two of these modules to replace both channels and saving the need for sixteen SAD512D.
The Oakley Sound DN34 BBD module uses four Panasonic MN3207 BBDs - although you can also use V3207 and BL3207 devices with equal success. High speed, high current, non overlapping dual clock driver circuitry allows usage of the 3207 device up to clock frequencies of 1.3MHz.
The sound when using the replacement board is almost identical to the original circuitry - the only small difference is a slight loss of gain when the delay time is very small. In practice this makes little difference, if any, to the effect heard, even when using the device in self oscillating mode or very resonant flanging.
Klark Teknik™ is a registered trade mark and is the property of its owner. Oakley Sound Systems are not affiliated with Klark Teknik™ and the use of their trade mark in these documents in no way means that Klark Teknik™ have endorsed this product.
An original issue 1 DN34 BBD PCB. Issue 1.1 is similar in layout but the solder mask is green not blue.
The four layer PCB is 103mm x 120mm in size and is connected to the DN-34's main PCB via a series of interconnects. Two way 0.1" headers allow screened cable or just single core multistrand cable to make the three audio, one control voltage and one clock connections. The main board needs to be slightly modified. Several components need to be removed from the board and one resistor needs to be replaced. This can be all done without removing the main board from the chassis if you are careful. The original ICs can simply be removed by pulling them from their sockets. Novice builders are recommended to unscrew the main board from the chassis to get at the underside of the main board for easier desoldering and soldering.
To calibrate the DN-34 and DN34 BBD an oscilloscope is required.
To replace the BBDs in both channels of the DN-34 two of these replacement PCBs are required.
Prices
DN34 BDD issue 1.1 PCB ............................. 36GBP each
Most of the other parts should be able to be purchased from you usual electronic component supplier. Please see the Builder's Guide for more details.
See the Oakley Sound ordering page for ordering information, shipping charges and payment methods.
All prices include VAT at UK rates. Shipping/postage is additional to these prices. See also the FAQ page.
Project Downloads
DN34_BBD issue 1 Builder's and Installation Guide
DN-34 Service Manual Original Service manual - no component values unfortunately.
Construction Guide Our handy guide to building Oakley DIY projects
Parts Guide Our handy guide to buying parts for Oakley DIY projects
Schematics are only available to purchasers of the PCB and will be sent via e-mail when the board(s) are shipped.
Klark Teknik™ is a registered trade mark and is the property of its owner. Oakley Sound Systems are not affiliated with Klark Teknik™ and the use of their trade mark in these documents in no way means that Klark Teknik™ have endorsed this product.
It is possible to use two Oakley Sound DN34 BBD boards to replace all sixteen SAD512D BBDs.
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