you are looking at DK25q HiFi hi-end speaker Open Baffle Speaker 1.4 Horn 15 inch bass aluminum !!! please any questions before buy are welcome i believe communication is the key between seller and customer. Attn:, Attn:, Attn: please note item will be sent direct from my warehouse in china, usually item will arrive to USA between 15 days and rest of the world up to 20 days maybe less, it will take 1-3 days to take it out from warehouse Because this home theater is too big Free Shipping worldwide Specification: Communication: Audio LineDisplay Screen: NoBattery: NoSpeaker Type: CombinationPower Source: NoneNumber of Loudspeaker Enclosure: 2Cabinet Material: WoodAudio Crossover: Three-WayBuilt-in Microphone: NoChannels: 2 (2.0)Feature: NoneIntelligent Personal Assistant: NoneOutput Power: 500WRemote Control: NoSupport Memory Card: NoPlayback Function: NoneVoice Control: NoMaterial: WoodSupport Apt-x: NoDisplay Screen: NoWaterproof: NoSupport APP: NoModel Number: DK25q Product description: Model: DK25q Material: wood Impedance: 4~8Ω Interface type: RCA interface Color classification: white, dark green, royal blue, deep wine red Weight (Kg): 70KG Speaker structure: Hifi pair box Speaker type: front Power: 250W Sensitivity: 87dB/mW 1. Features of Open Baffle Speaker 1. The playback sound without sound dyeing, the true color of the faithful unit; 3. Space does not need to be processed and standing waves will not be generated; 4. The listening position that is not restricted by the emperor's position, even if it is off-axis by 30 degrees, the knot image is in the center However, Open Baffle Speaker also has its obvious defects: 1) Under the same conditions: inverting box, the low-frequency resonance frequency is the lowest, but the rate of decline is the steepest, -18dB; closed box, followed by the low-frequency resonance frequency, the rate of decline is -12dB; Open baffle, low frequency resonance frequency is the earliest, the drop rate is -6~-10dB, the reason for the indefinite value is because the size and area of Open Baffle Speaker are different 2) In the middle and low frequency bands, due to the effect of Open Baffle Speaker, there will be a raised peak of about 3~6dB. Depending on the size of Open Baffle Speaker, it will appear in the frequency band of 200~400hz; 3) In the middle and high frequency bands, due to the effect of Open Baffle Speaker, a sag valley will also appear. Product stereotypes Technical parameters - DK28q (dual 18 inch bass) Appearance size: 1560 (height) *600 (width) *600 (length) mm Frequency range: 28 (-3dB) ~ 40Khz Sensitivity: 88dB Frequency response (SPL) curve Technical parameters - DK25q (dual 15 inch bass) Appearance size: 1560 (height) *600 (width) *600 (length) mm Frequency range: 35 (-3dB) ~ 40Khz Sensitivity: 88dB Frequency response (SPL) curve Units and accessories If you are in 110V area, please tell us. About the international shipping/transportation cost, it isn't accuracy on some countries, if it is expensive, please contact us! Sometimes we can find a cheap way, we must 100% reply to you! Please carefully check the packing/box/parcel when the your receiving the parcel. Because of the sales quantity reason, we have no power to build after-sales service center in your local. But our products price is more cheaper under the same quality, we are trying to provide better service!The warranty period for all our items is 2 years. Within 2 years, we can provide repairing parts free. and you needn't pay the shipping fee from China, there need buyer and seller cooperation of problem fault diagnosis. After 2 years date, we can provide repairing parts free. But the buyer should pay the shipping fee from China.