Great speaker for my Tone King Imperial MK II guitar amp. The stock speaker had a ceramic magnet and the Celestion Ruby with alnico magnet further enhanced the sound of this excellent amplifier. The speaker sounds very vintage: warm, slightly darker (mitigated those unpleasant high frequencies), nice full bass and midrange. Even the effects on the amplifier - reverb and tremolo sound even better. The speaker is relatively new, still not fully tuned, so the sound will only get better in the coming weeks. Thank you Boris for your kindness and help with the purchase.