SKU: 68652837824

STAX SRM-400S Solid State Driver

Sale price$1125.00 Regular price$1250.00
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Description

STAX SRM-400S Solid State DriverMiddle class semiconductor driver unit is renewed. New DC amplifier which FET are installed in all stages. STAX introduces a new semiconductor driver unit SRM 400S, the successor model of SRM 353X. STAX custom made low noise DUAL FET is installed on First Stage. And FET is also installed on Last Stage. The characteristics of right FET and left FET are measured strictly. Selected FET are installed as well as SRM 700S. SRM 400S succeeds to the design

Middle-class semiconductor driver unit is renewed.
New DC amplifier which FET are installed in all stages.

STAX introduces a new semiconductor driver unit SRM-400S, the successor model of SRM-353X. STAX custom-made low noise DUAL FET is installed on First Stage. And FET is also installed on Last Stage. The characteristics of right FET and left FET are measured strictly. Selected FET are installed as well as SRM-700S. SRM-400S succeeds to the design and the manufacturing method of the high end model SRM-700S, the amplifier which FET are installed in all stages.

In addition to the conventional power transformer for the high voltage circuit, the newly designed power transformer with the winding for the low voltage circuit is installed in SRM-400S. The low voltage winding enables to improve the power efficiency and achieve further power saving and better sound quality than the conventional driver units such as SRM-353X.

The new chassis which is more rigid than the conventional model is installed. The chassis has a hybrid structure using a lot of non-magnetic aluminum and further reduces the effect of the environmental noise factors such as vibrations. The inputs are RCA and XLR, the mutual exclusion inputs. The custom made concentric dual volume knob which is common to STAX products and RCA PARALLEL OUT functions are installed same as the conventional driver units. All electric components are strictly selected considering the environment. Also the sound quality and the performance is improved. The complete DC amplifier configuration that the signal circuit includes no coupling condensers is one of the biggest traditional features.

SRM-400S takes over the high resolution sound which is unique to the semiconductor circuit and dynamic low range sound reproduction. Simultaneously, the good sound balance is further pursued than SRM-353X. From the low range to the high range, the sound of each range is well harmonized. Not only for the combination with the advanced lambda series, SRM-400S is also ideal for the upgrading from the entry level SRS-3100. This is the promising new model which covers from beginners to intermediates among the renewed driver unit lineup.

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    Exchange/Return Notes
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    SKU: 68652837824

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    Great dress
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    These are without a doubt the most comfortable shoes/boots, I with a pointed toe, that I have ever worn. The heel is a perfect height to elevate your look without forcing your foot too far forward into the toe box. I have worn these all day long, and have never had them pinch my toes. I’ve even worn them walking through cobblestone streets in London without discomfort. These boots also look amazing with a skirt, dress, or even a pair of jeans. The color is rich and the suede is butter soft. They fit true to size. I wear a 6.5 M. I find this true with all of the shoes I own from Sam Edelman. The quality is much better than the price suggests. I highly recommend these boots. You won’t regret your purchase!
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    Los Angeles, US
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    Calf shaft runs big
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    Beautiful suede boots. The shaft does run a bit loose so if you’re on the fence about ordering a wide version you may want to try the regular size first. I sized up half a size so I could wear a sock but probably didn’t need to. The kitten heel height is perfect for my comfort. I liked these so much I got them in dark walnut and black.
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    Dallas, US
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    Stylish boot with low heel. Good suede and rubber no-slip sole. I purchased wide calf and they fit well. My calf measures 16.5 inches. I purchased also in brown and chianti colors.
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    Reviewed in the United States on March 25, 2026

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