Bottlehead Forum

General Category => General Discussion => Topic started by: tube747 on January 14, 2025, 08:42:19 PM

Title: Input Impedance of Kaiju 300B Amplifier
Post by: tube747 on January 14, 2025, 08:42:19 PM

Hello!
What is the input impedance of Kaiju 300B Amplifier?

Thanks!

Title: Re: Input Impedance of Kaiju 300B Amplifier
Post by: Doc B. on January 15, 2025, 05:10:16 AM

100K ohms

Title: Re: Input Impedance of Kaiju 300B Amplifier
Post by: Paul Birkeland on January 15, 2025, 05:38:25 AM

It will dip to more like 65K at 20kHz, though that assumes that both trim pots are turned all the way up. 

Title: Re: Input Impedance of Kaiju 300B Amplifier
Post by: tube747 on January 22, 2025, 11:12:21 PM

I still have few pairs of Magnequest SE output transformer that bought from your company long time ago, can i use it on the  Kaiju?

Thanks!

Title: Re: Input Impedance of Kaiju 300B Amplifier
Post by: Paul Joppa on January 23, 2025, 03:43:20 AM

Magnequest Mike made a lot of different transformers - which ones do you have? There are a few that could work, with suitable modifications (minor circuit changes and a few new mounting holes.) It won't save money (custom packing is costly) and Bottlehead strongly recommends building the kit debugging it in stock form before making changes; otherwise we are not able to provide as much useful help when things go wrong. But it can be quite satisfying to make use of something you've laid away long ago!