LL9226XL Lundahl MC-Übertrager improved LL9226 MC transformer

Lundahl LL9226XL – flexible MC step-up transformer with 1:5, 1:10 or 1:20 ratios

The Lundahl LL9226XL is a moving-coil step-up transformer for passively matching low-output MC cartridges to an MM phono input. Three manufacturer-recommended winding arrangements provide 1:5, 1:10 or 1:20 ratios.

Compared with the LL9226, the XL version has approximately 40% more core cross-sectional area. Lundahl states that this increases headroom and reduces transformer distortion. The uncut amorphous cobalt strip core is enclosed in a double-thickness mu-metal case.

Suitable applications

• MC cartridges below approximately 100 Ω source impedance at 1:5
• MC cartridges below approximately 50 Ω source impedance at 1:10
• Low-output MC cartridges below approximately 25 Ω at 1:20
• Denon DL-103 using a suitable 1:10 connection
• Denon DL-103R and Audio-Technica AT33PTG/II using a suitable 1:10 or 1:20 connection
• Mono and stereo phono stages; stereo requires two transformers

Technical data

Product type

Moving-coil step-up transformer

Model

LL9226XL

Basic winding ratio

1+1+1+1:10+10

Recommended ratios

1:5, 1:10 and 1:20

Voltage gain at 1:5

Ideally approximately 14.0 dB

Voltage gain at 1:10

Ideally 20.0 dB

Voltage gain at 1:20

Ideally approximately 26.0 dB

Core material

Uncut cobalt-based amorphous strip core

Core cross-sectional area

Approximately 40% greater than the LL9226

Magnetic shielding

Double-thickness mu-metal enclosure

Faraday shield

Not fitted

DC resistance per primary winding

Approx. 5.5 Ω

DC resistance per secondary winding

Approx. 145 Ω

Frequency response

7 Hz to 70 kHz within ±1 dB

Extended frequency response

4 Hz to 90 kHz within ±1.5 dB

Frequency-response test conditions

-10 dBu, Alternative A, 50 Ω source and 47 kΩ load

Distortion

Below 0.1% at -2 dBu and 50 Hz with a 40 Ω source and series-connected primaries

Primary no-load impedance

Typically approximately 5 kΩ at 0 dBu and 50 Hz with all primaries in series

Winding-to-winding dielectric test

3 kV AC

Winding-to-core dielectric test

1.5 kV AC

Dimensions above the PCB

Approx. 33 × 27 × 16 mm

Weight

Approx. 42 g

Pin spacing

2.54 mm with a row spacing of 22.86 mm

Number of connections

Fifteen populated pins; the numbering omits pin 12

Recommended PCB hole diameter

Approx. 1.3 mm

Compatibility

Pin-compatible with the LL9226 but housed in a larger enclosure

Recommended connection alternatives

Alternative A – 1:5

Approx. 22 Ω primary and 290 Ω secondary copper resistance; recommended for MC cartridges below approximately 100 Ω

Alternative B – 1:5

Not recommended by the manufacturer

Alternative C – 1:10

Approx. 5.5 Ω primary and 290 Ω secondary copper resistance; recommended for MC cartridges below approximately 50 Ω

Alternative D – 1:10

Not recommended by the manufacturer

Alternative E – 1:20

Approx. 1.4 Ω primary and 290 Ω secondary copper resistance; recommended for MC cartridges below approximately 25 Ω

Reflected load with a 47 kΩ MM input

1:5

Approximately 1,880 Ω ideal reflected cartridge load

1:10

Approximately 470 Ω ideal reflected cartridge load

1:20

Approximately 117.5 Ω ideal reflected cartridge load

Calculation

MM input resistance divided by the square of the turns ratio; winding resistance and additional loading resistors modify the actual value

Selection for specific MC cartridges

Denon DL-103

0.3 mV output and 40 Ω output impedance; 1:10 ideally provides approximately 3 mV and meets the Lundahl guidance for sources below 50 Ω

Denon DL-103R

0.25 mV and 14 Ω; 1:20 ideally provides approximately 5 mV and remains within the manufacturer guidance for sources below 25 Ω

Audio-Technica AT33PTG/II

0.3 mV and 10 Ω; 1:20 ideally provides approximately 6 mV, while 1:10 provides approximately 3 mV

Important headroom note

The greatest calculated output is not automatically the best choice; consider MM gain, input sensitivity and overload margin

Grounding and stereo installation

The LL9226XL has no Faraday shields. Lundahl therefore recommends a common ground reference for the primary and secondary sides. Adapt the exact grounding arrangement to the phono stage, tonearm cable and enclosure.

Stereo requires two LL9226XL transformers. Both channels should use identical wiring, termination, cable routing and physical orientation.

The transformer handles extremely small signals. Use short wiring, effective shielding and adequate distance from mains transformers, motors and relays.

Comparison with the LL9226

The LL9226XL is pin-compatible and uses the same basic winding structure as the LL9226. Lundahl states that the larger amorphous cobalt core increases headroom and reduces transformer distortion. The larger enclosure still requires a physical-clearance check.

Questions about selection and use

Which MC step-up transformer suits the Denon DL-103 with 40 Ω and 0.3 mV output?

Lundahl LL9226XL is a suitable technical match in recommended 1:10 Alternative C. It ideally provides approximately 3 mV to the MM input and is intended for MC sources below 50 Ω.

Which Lundahl SUT suits the low-impedance DL-103R or AT33PTG/II?

Lundahl LL9226XL can use recommended 1:20 Alternative E with these low-impedance cartridges. The DL-103R ideally provides approximately 5 mV and the AT33PTG/II approximately 6 mV; verify MM gain and headroom first.

Can the LL9226XL be configured for 1:5, 1:10 and 1:20 ratios?

Yes, the LL9226XL can be configured for 1:5, 1:10 or 1:20 through the documented winding connections. Use recommended Alternatives A, C and E; Alternatives B and D should not be used.

Is the LL9226XL pin-compatible with the LL9226?

Yes, Lundahl states that the LL9226XL is pin-compatible with the LL9226. Its enclosure is larger, and the manufacturer drawing shows fifteen populated pins with number 12 omitted.