A-137 is a voltage controlled Wave Multiplier. The basic idea of a wave multiplier is to multiply the waveform of an incoming signal (e.g. triangle/saw/sine from a VCO) within one period of the waveform. This leads to additional harmonics of the incoming signal. The period and consequently the pitch of the signals remains unchanged (in contrast to frequency multiplication e.g. with the PLL module A-196). The A-137 works as a kind of "inverse low pass filter", i.e. it adds a lot of harmonics to a signal that contains none or only a few harmonics (e.g. sine or triangle waveform). In contrast to that a low pass filter (e.g. A-120) removes harmonics from a signal that contains a lot of harmonics (e.g. saw or rectangle waveform). Consequently the best results are obtained in combination with input signals poor in harmonics (e.g. sine or triangle). The A-137 can be used with signals rich in harmonics too (e.g. saw) but the effect is not as remarkable as for triangle or sine waves. For rectangle signals none or only little effects are obtained.
The A-137 is a very sophisticated wave multiplier that offers much more features, more controls and more waveform manipulations than other wave multipliers available so far. In addition all parameters are both manually adjusted and controlled by external voltages. These are the features of the module:
Controls:
Input Level (to adjust the input level for best effect of the succeeding controls)
Multiples (number of waveform multiplications, manual control)
Harmonics (additional effect that adds more harmonics similar to the resonance/emphasis control of filters, manual control)
Folding Level (controls upper and lower folding level, manual control)
Symmetry (controls symmetry between upper and lower folding level, manual control)
Inputs/Outputs:
Audio In (also suitable for control signals)
Multiples CV In (with attenuator)
Harmonics CV In (with attenuator)
Folding Level CV In (with attenuator)
Symmetry CV In (with attenuator)
Audio Out (resp. processed control signal output)
The Multiples parameter (manual and ext. CV) defines the number of basic wave multiplications within one period. With the Folding Level and Symmetry parameter (both manual and ext. CV) the upper and lower clipping levels of the wave folder units are controlled. The Harmonics parameter (manual and ext. CV) adds some harmonic content by sharpening the waveform edges and adding overshoot peaks. It works a little bit like the resonance control of a VCF. The module is fully DC coupled, i.e. even control signal can be processed with the modules.
Width: 14 HP / 70.8 mm
Depth: 65 mm (measured from the rear side of the front panel)
Current: +40mA (+12V) / -20mA (-12V)
How much is my shipping?
Shipping is automatically calculated before you submit your payment information. Simply add items to your cart and proceed to the checkout page, where you'll be offered shipping options and their prices. In the UK, 'next working day' shipping is free if the order value is over £150, and £5 otherwise. We can also ship on a 'next working day before 12pm' service, which costs £6 for orders over £150 and £7.50 for orders under £150.
Shipping to mainland EU typically costs between £7 and £20, depending on the shipping method and the size and weight of the order.
Do you ship to my country?
Almost certainly - the site will give you an estimate of shipping costs if you add an item to the cart and then enter your country and postcode. If you have specific requirements (such as if you prefer UPS over FedEx, for example) then let us know in advance and we'll try to work something out for you.
Shipping methods
We use a combination of DPD, Royal Mail and Parcelforce for the UK, and for international orders it's either DHL, FedEx, UPS, Royal Mail or Parcelforce depending on where you are in the world. If you have a particular preference then try to let us know BEFORE you order so we can look into it for you. Please note that there may occasionally be additional shipping charges if you live in a remote area, depending on what surcharges are applied by the shipper. We'll get in touch to discuss this with you in such cases.
Dispatch times
For UK orders, we aim to dispatch the same working day if we get the order before 16:00. If you have a really urgent situation then of course drop us an email before ordering and we'll always do our absolute best to accommodate you.
For international orders, we normally dispatch the same day if we get the order before 13:00 but again, occasionally it might be the next day before we can send it out, and sometimes the couriers may come to collect a little earlier than scheduled which would also push an order into the next day.
Saturday/Sunday shipping
If you're in the UK and you order before 16:00 on a Friday then we can send something for a Saturday or Sunday delivery with DPD. This is FREE for order values over £350, £5 for order values between £75 and £250, and £7 for order values under £75. (NB: this applies to UK mainland addresses only). Please note that any orders placed after 16:00 on a Friday will ship on the Monday.
International shipping times
Since April 2020, the couriers we use have suspended guarantees for shipping times, so even though we're paying them for priority services - 24-48 hours for most of the world - in practice it's often an extra day on top and sometimes it can be longer. There is absolutely nothing we can do about this, unfortunately. If you are outside the UK and it's a life-or-death situation where you absolutely MUST have that passive mult for the next day then... it may be better to find a local supplier.
Pre-orders
If a product is listed as a pre-order, it means we've ordered it from the supplier but it's not physically in stock yet. The product listing will include an estimated shipping date based on the best information we have from the supplier, but do bear in mind this is subject to change and is not a guaranteed date.
If you place an order containing a mixture of in-stock and pre-order items, we'll normally hold off on shipping anything until the pre-order item(s) have arrived, rather than splitting it into multiple shipments. If you need the in-stock items sooner, we'd recommend placing separate orders. As always, please get in touch if you have questions.
Product Overview
A-137 is a voltage controlled Wave Multiplier. The basic idea of a wave multiplier is to multiply the waveform of an incoming signal (e.g. triangle/saw/sine from a VCO) within one period of the waveform. This leads to additional harmonics of the incoming signal. The period and consequently the pitch of the signals remains unchanged (in contrast to frequency multiplication e.g. with the PLL module A-196). The A-137 works as a kind of "inverse low pass filter", i.e. it adds a lot of harmonics to a signal that contains none or only a few harmonics (e.g. sine or triangle waveform). In contrast to that a low pass filter (e.g. A-120) removes harmonics from a signal that contains a lot of harmonics (e.g. saw or rectangle waveform). Consequently the best results are obtained in combination with input signals poor in harmonics (e.g. sine or triangle). The A-137 can be used with signals rich in harmonics too (e.g. saw) but the effect is not as remarkable as for triangle or sine waves. For rectangle signals none or only little effects are obtained.
The A-137 is a very sophisticated wave multiplier that offers much more features, more controls and more waveform manipulations than other wave multipliers available so far. In addition all parameters are both manually adjusted and controlled by external voltages. These are the features of the module:
Controls:
Input Level (to adjust the input level for best effect of the succeeding controls)
Multiples (number of waveform multiplications, manual control)
Harmonics (additional effect that adds more harmonics similar to the resonance/emphasis control of filters, manual control)
Folding Level (controls upper and lower folding level, manual control)
Symmetry (controls symmetry between upper and lower folding level, manual control)
Inputs/Outputs:
Audio In (also suitable for control signals)
Multiples CV In (with attenuator)
Harmonics CV In (with attenuator)
Folding Level CV In (with attenuator)
Symmetry CV In (with attenuator)
Audio Out (resp. processed control signal output)
The Multiples parameter (manual and ext. CV) defines the number of basic wave multiplications within one period. With the Folding Level and Symmetry parameter (both manual and ext. CV) the upper and lower clipping levels of the wave folder units are controlled. The Harmonics parameter (manual and ext. CV) adds some harmonic content by sharpening the waveform edges and adding overshoot peaks. It works a little bit like the resonance control of a VCF. The module is fully DC coupled, i.e. even control signal can be processed with the modules.
Technical Specs
Shipping Details
How much is my shipping?
Shipping is automatically calculated before you submit your payment information. Simply add items to your cart and proceed to the checkout page, where you'll be offered shipping options and their prices. In the UK, 'next working day' shipping is free if the order value is over £150, and £5 otherwise. We can also ship on a 'next working day before 12pm' service, which costs £6 for orders over £150 and £7.50 for orders under £150.
Shipping to mainland EU typically costs between £7 and £20, depending on the shipping method and the size and weight of the order.
Do you ship to my country?
Almost certainly - the site will give you an estimate of shipping costs if you add an item to the cart and then enter your country and postcode. If you have specific requirements (such as if you prefer UPS over FedEx, for example) then let us know in advance and we'll try to work something out for you.
Shipping methods
We use a combination of DPD, Royal Mail and Parcelforce for the UK, and for international orders it's either DHL, FedEx, UPS, Royal Mail or Parcelforce depending on where you are in the world. If you have a particular preference then try to let us know BEFORE you order so we can look into it for you. Please note that there may occasionally be additional shipping charges if you live in a remote area, depending on what surcharges are applied by the shipper. We'll get in touch to discuss this with you in such cases.
Dispatch times
For UK orders, we aim to dispatch the same working day if we get the order before 16:00. If you have a really urgent situation then of course drop us an email before ordering and we'll always do our absolute best to accommodate you.
For international orders, we normally dispatch the same day if we get the order before 13:00 but again, occasionally it might be the next day before we can send it out, and sometimes the couriers may come to collect a little earlier than scheduled which would also push an order into the next day.
Saturday/Sunday shipping
If you're in the UK and you order before 16:00 on a Friday then we can send something for a Saturday or Sunday delivery with DPD. This is FREE for order values over £350, £5 for order values between £75 and £250, and £7 for order values under £75. (NB: this applies to UK mainland addresses only). Please note that any orders placed after 16:00 on a Friday will ship on the Monday.
International shipping times
Since April 2020, the couriers we use have suspended guarantees for shipping times, so even though we're paying them for priority services - 24-48 hours for most of the world - in practice it's often an extra day on top and sometimes it can be longer. There is absolutely nothing we can do about this, unfortunately. If you are outside the UK and it's a life-or-death situation where you absolutely MUST have that passive mult for the next day then... it may be better to find a local supplier.
Pre-orders
If a product is listed as a pre-order, it means we've ordered it from the supplier but it's not physically in stock yet. The product listing will include an estimated shipping date based on the best information we have from the supplier, but do bear in mind this is subject to change and is not a guaranteed date.
If you place an order containing a mixture of in-stock and pre-order items, we'll normally hold off on shipping anything until the pre-order item(s) have arrived, rather than splitting it into multiple shipments. If you need the in-stock items sooner, we'd recommend placing separate orders. As always, please get in touch if you have questions.
