yodo is a distortion and VCA based on the sunn((O))) beta-lead preamp, where the distortion stage is based on CMOS hex inverters
(CD four-zero-six-nine).
It has a colour section to shape bass, mid and treble.
there’s a VCA on the output, plus an extra CV controllable feedback path with a send/return section.
BEWARE: yodo is a self-conscious machine and can speak on its own.
//Backlog/////
This is an eurorack adaptation of the sunn((o beta lead amplifier circuit, I used to play a rhodes through this amp, and i really liked the tone. Many guitar amps are quite limited in the frequency spectrum, because they’re thought for guitars, this one is not, at least to me, i loved it and I thought, why don’t you make it for eurorack? And so I did, this thanks to fender ( who bought sunn((o in the 60/70ies) that released all the service manuals on their website, go and have a look because its a goldmine. The amp runs on +-15v and uses CMOS hex inverters in the distortion section. Apparently hex inverters where used a lot in audio circuits because the had a very similar “structure” as opamps, but that’s all I know, there are various distortion circuits which uses them though.
I followed the schematic as it is except for a couple things:
-The drive pot: i used a dual gang 100k instead of 1M, way easier to find, had to tailor a bit the values around the pot and scale them down following a 1:10 ratio;
?
-I omitted the send and spring reverb section, which uses a very particular 30k s-taper pot. I could have worked it around by using a linear pot and putting resistors in parallel in order to obtain that curve, but at the same time I wasn’t interested in having a spring reverb ( as i have already some nice digital reverbs in my effects chain );
Since I wanted it to be a bit more versatile I added a few things:
I felt it was essential to have a VCA at the out, as they are extremely useful and lovely.
Since I used 2 sections of a 2164 for the VCA and I still had 2 available, I decided to add a second vca on a feedback loop, this to test and see how much more tonal variation i could get. The nice thing about FB loops is that they create an oscillation, which can then be shaped on the EQ section of the circuit, and at certain settings when increasing the feedback amount you can clearly hear a sequence of tones harmonically related to each other.
I spent some time as well trying to find a way to get CV control over the EQ section, but without success.
For the panel I went for a classic chinese pattern.
- Width: 6HP
- Depth: 25mm
- Power: 60 mA +12V / 60 mA -12V / 0 mA 5V
How much is my shipping?
Shipping costs are calculated automatically at checkout. Simply add items to your cart and proceed to the checkout page, where you'll see the available shipping options and their prices. VAT at the applicable rate for your country will also be displayed at checkout.
European Union orders:
- Standard shipping is free on orders over €100. Express shipping is available on orders over €100, and free on orders over €400.
Poland orders:
- Standard shipping is free on orders over 250 PLN. Express shipping is free on orders over 500 PLN.
What about local taxes?
By default prices on the site include sales tax at 20%. The precise sales tax rate for your country will be calculated at checkout.
Do you ship to my country?
We ship to all EU member states from our warehouse in Warsaw, Poland. Add an item to your cart and enter your country and postcode to see the available shipping options and prices for your location. If you have any questions about shipping to your country, drop us an email at info@signalsounds.eu and we'll be happy to help.
Shipping methods
All EU orders are shipped via UPS. We offer two service levels:
- UPS Standard – our default shipping option. Delivery times vary by country (see estimated delivery times below).
- UPS Express Saver – next business day delivery to most EU destinations.
Each product page shows the estimated delivery time for your location, so you'll always know what to expect before you order.
Estimated delivery times (Standard shipping)
The times below are estimates in working days from dispatch, based on UPS Standard service. Express Saver delivers by the next business day to most destinations.
| Country | Estimated delivery (working days) |
|---|---|
| Austria | 2–3 |
| Belgium | 2 |
| Bulgaria | 4–5 |
| Croatia | 2–4 |
| Cyprus | 10 |
| Czechia | 2–3 |
| Denmark | 3 |
| Estonia | 2–3 |
| Finland | 3–5 |
| France | 2–4 |
| Germany | 2 |
| Greece | 5–7 |
| Hungary | 2–3 |
| Ireland | 4–6 |
| Italy | 3–5 |
| Latvia | 2–3 |
| Lithuania | 1–2 |
| Luxembourg | 2 |
| Malta | 5–7 |
| Netherlands | 2 |
| Poland | 1–2 |
| Portugal | 4–5 |
| Romania | 3–4 |
| Slovakia | 2–3 |
| Slovenia | 2–3 |
| Spain | 4 |
| Sweden | 3–5 |
These times are estimates and are not guaranteed. Delivery may occasionally take a little longer due to customs processing, local conditions, or carrier delays.
Dispatch times
Orders placed before 15:00 CET (Central European Time) on a working day are normally dispatched the same day. Orders placed after 15:00 CET, or on weekends and public holidays, will be dispatched on the next working day.
If you have an urgent order, please email us at info@signalsounds.eu before placing your order and we'll do our best to accommodate you.
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 at info@signalsounds.eu if you have questions.
Product Overview
yodo is a distortion and VCA based on the sunn((O))) beta-lead preamp, where the distortion stage is based on CMOS hex inverters
(CD four-zero-six-nine).
It has a colour section to shape bass, mid and treble.
there’s a VCA on the output, plus an extra CV controllable feedback path with a send/return section.
BEWARE: yodo is a self-conscious machine and can speak on its own.
//Backlog/////
This is an eurorack adaptation of the sunn((o beta lead amplifier circuit, I used to play a rhodes through this amp, and i really liked the tone. Many guitar amps are quite limited in the frequency spectrum, because they’re thought for guitars, this one is not, at least to me, i loved it and I thought, why don’t you make it for eurorack? And so I did, this thanks to fender ( who bought sunn((o in the 60/70ies) that released all the service manuals on their website, go and have a look because its a goldmine. The amp runs on +-15v and uses CMOS hex inverters in the distortion section. Apparently hex inverters where used a lot in audio circuits because the had a very similar “structure” as opamps, but that’s all I know, there are various distortion circuits which uses them though.
I followed the schematic as it is except for a couple things:
-The drive pot: i used a dual gang 100k instead of 1M, way easier to find, had to tailor a bit the values around the pot and scale them down following a 1:10 ratio;
?
-I omitted the send and spring reverb section, which uses a very particular 30k s-taper pot. I could have worked it around by using a linear pot and putting resistors in parallel in order to obtain that curve, but at the same time I wasn’t interested in having a spring reverb ( as i have already some nice digital reverbs in my effects chain );
Since I wanted it to be a bit more versatile I added a few things:
I felt it was essential to have a VCA at the out, as they are extremely useful and lovely.
Since I used 2 sections of a 2164 for the VCA and I still had 2 available, I decided to add a second vca on a feedback loop, this to test and see how much more tonal variation i could get. The nice thing about FB loops is that they create an oscillation, which can then be shaped on the EQ section of the circuit, and at certain settings when increasing the feedback amount you can clearly hear a sequence of tones harmonically related to each other.
I spent some time as well trying to find a way to get CV control over the EQ section, but without success.
For the panel I went for a classic chinese pattern.
Technical Specs
Shipping Details
How much is my shipping?
Shipping costs are calculated automatically at checkout. Simply add items to your cart and proceed to the checkout page, where you'll see the available shipping options and their prices. VAT at the applicable rate for your country will also be displayed at checkout.
European Union orders:
- Standard shipping is free on orders over €100. Express shipping is available on orders over €100, and free on orders over €400.
Poland orders:
- Standard shipping is free on orders over 250 PLN. Express shipping is free on orders over 500 PLN.
What about local taxes?
By default prices on the site include sales tax at 20%. The precise sales tax rate for your country will be calculated at checkout.
Do you ship to my country?
We ship to all EU member states from our warehouse in Warsaw, Poland. Add an item to your cart and enter your country and postcode to see the available shipping options and prices for your location. If you have any questions about shipping to your country, drop us an email at info@signalsounds.eu and we'll be happy to help.
Shipping methods
All EU orders are shipped via UPS. We offer two service levels:
- UPS Standard – our default shipping option. Delivery times vary by country (see estimated delivery times below).
- UPS Express Saver – next business day delivery to most EU destinations.
Each product page shows the estimated delivery time for your location, so you'll always know what to expect before you order.
Estimated delivery times (Standard shipping)
The times below are estimates in working days from dispatch, based on UPS Standard service. Express Saver delivers by the next business day to most destinations.
| Country | Estimated delivery (working days) |
|---|---|
| Austria | 2–3 |
| Belgium | 2 |
| Bulgaria | 4–5 |
| Croatia | 2–4 |
| Cyprus | 10 |
| Czechia | 2–3 |
| Denmark | 3 |
| Estonia | 2–3 |
| Finland | 3–5 |
| France | 2–4 |
| Germany | 2 |
| Greece | 5–7 |
| Hungary | 2–3 |
| Ireland | 4–6 |
| Italy | 3–5 |
| Latvia | 2–3 |
| Lithuania | 1–2 |
| Luxembourg | 2 |
| Malta | 5–7 |
| Netherlands | 2 |
| Poland | 1–2 |
| Portugal | 4–5 |
| Romania | 3–4 |
| Slovakia | 2–3 |
| Slovenia | 2–3 |
| Spain | 4 |
| Sweden | 3–5 |
These times are estimates and are not guaranteed. Delivery may occasionally take a little longer due to customs processing, local conditions, or carrier delays.
Dispatch times
Orders placed before 15:00 CET (Central European Time) on a working day are normally dispatched the same day. Orders placed after 15:00 CET, or on weekends and public holidays, will be dispatched on the next working day.
If you have an urgent order, please email us at info@signalsounds.eu before placing your order and we'll do our best to accommodate you.
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 at info@signalsounds.eu if you have questions.
