Je te mets la description de l'ampli telle qu'elle était sur le site de Rat valve amps :
The Amp is All Valve, 'Class A', 'Single Ended', 'Cathode Bias' - In the New 'Head' Format. There is NO Heater 'Buzz' - NO Circuit 'HUM' - It uses a Nice 3 Stage Gain Design. Limited 'Clean' Headroom but Tons of Great Marshall 'Crunch' - The Build Quality is good and the Amp Looks and Sounds Fantastic.
This Marshall 'C5H' is a 'REAL' All Valve Amp - No Transistors, Chips, Digital Processing or SMT (Surface-Mount Technology). Totally Made in the UK.
On the Test Bench the 'Stock' Amp is Producing 5 Watts RMS and about 10 Watts Peak Power into 8 or 16 Ohms.
I think the Amp Sounds Great but I wanted it to have a bit more 'BITE' so I converted it to 'Dual Parallel'. The Amp now Produces 10 Watts RMS and about 16 Watts Peak Power. I have been careful to keep the Tone Structure the same and just Boost the Output Power. I have Also added a '5Y3WGTA' Valve Rectifier.
The Stock Marshall Transformers do Not allow any increase in Output Power, they are designed for a 5 Watt Amp, and that's it. I had to change both the Mains Power -and- Output Transformer in order to get any increase in Output Power.
The Overall effect of these Changes is a Much more 'Focused' Sound. The Voice of the Amp is Very 'Marshall Plexi' although this can be changed with the New 'Bias' -and- 'Gain' Switches. There is more Clean Headroom and The Bass is 'Tighter'. Turn it Up and the Amp is more 'Agressive'. The Valve Rectifier Smooth's things out Nicely and the Natural Sustain from this Amp is Much Improved.
- Additional 'RAT' Features -
1. - 'OPR' - Output Power Reduction.
www.ratvalveamps.com/power-scaling'OPR' lets you get a true 'Cranked Amp Sound' at VERY Low Volume Levels - Fat Harmonics - Sustain a Mile Long - the Full Works, but at a Volume level you can 'Talk' over. Simple to use, Just like a Normal Volume Control, but as you 'Dial Down the Power' - The Volume Drops but the Tone is Maintained. The Output Power of the Amplifier can be Varied from 100% down to Less than 1% of the Full Rating - Fully Maintaining the Warm Tone and Natural Harmonics of the Output Valves. Waste Heat from the Output Stage is Dramatically reduced as the Power is Dialled down, Greatly Extending Valve Life.
2. - I have Converted the Amp Output Stage to 'Dual Parallel'. This Runs 2x Marshall JJ 'EL84' Valves Side-by-Side and doubles the Output Power to 10 Watts RMS. The Class 'A', Single Ended, Cathode Bias configuration has been maintained. In order to do this I had to fit a New 'TCE' Mains Transformer and a Hammond '125DSE' Output Transformer. The Amp now has some Great 'BITE' to it.
3. - With the extra Power Available from the New Mains Transformer I was able to fit the RAT 'TRI-Rectifier' System using a NOS Jan/Philips '5Y3WGTA' Valve-
www.ratvalveamps.com/tri-recti(...)d-sag
Using the Valve Rectifier there is now some Fantastic 'SAG' Available from the Amp. Even more 'Plexi' Sounding.
4. - Variable Boost Footswitch - The Boost Footswitch has a Built-In Gain Control. The Footswitch Connects to the Back of the Amp and you can set Just how much Gain you want with A Rotary Control located next to the Push-Button On/Off Switch. It Works Great and Gives a HUGE Boost to the 'MIDS' and Harmonics. A Red LED Illuminates when 'Boost' is Selected.
5. - Series FX Loop - 'Send and Return' - Configured for 'Stomp Box' Type Effects (High Impedance). The 'Send' Socket can also be used as a PREAMP 'Line Out' for connection to a Slave Amp, Mixing Desk (DI) or Recorder. The 'Return' Socket can also be used for Direct Access to the Valve Power Amp, (Master Volume Control Active) - For use with an External Preamp or Multi-Effects Processor Unit.
6. Master Volume Control - Allows Preamp Overdrive -or- Power Amp Overdrive -or- Both.
7. 2x Speaker Outputs with Impedance Select Switch - 4, 8 or 16 Ohms. This is a much better setup than Stock. You can now Connect One -or- Two Cabinets and simply select the Correct Impedance.
8. Standby Switch - The Stock Amp does not have a 'Standby' Switch, so I have Added one to the Front Panel.
9. - '3x Bias' -and- '3x Gain' Switches.
www.ratvalveamps.com/preamp-bi(...)-gain
This gives you 9 Combinations of 'Voice' settings on the Preamp Valves. From 'Clean' -to- 'Major Crunch' - it makes the Amp a lot more Versatile with a high chance that you can find the sound you want.
10. - Modified 'Tone Stack' - The Factory Tone Controls do not allow total Tone Control, they Sweep in a 'Preset Range' - The RAT Modified Treble, Middle and Bass controls now Sweep from 'Zero-to-Max' on each Frequency.
11. - Dedicated 'Line Out' Socket - For Direct Connection (DI) to a Mixing Desk, Recorder or Slave Amp. The 'Line Out' Signal is Speaker Emulated (Open Back Cab) and taken from the Output Transformer, it can be used with-or-without a Speaker connected to the Amp.
12. - Headphone Socket - Uses Standard Stereo Headphones - The Headphone Output can be used with-or-without a Speaker connected to the Amp.
13. - Auto-Switching 'Dummy Load' on both Speaker Outputs. Protects the Amp from Destruction caused by Accidental 'Switch On' with NO Speakers Connected.
14. - The Valves are - 2x Marshall 'ECC83' - 2x Marshall JJ 'EL84' - 1x NOS Jan/Phillips '5Y3WGTA'.
15. - Full RAT User Manual detailing all of the Modifications.
16. - All Amps are 'PAT' Approved -
www.ratvalveamps.com/pat-approval
- And Finally -
A few words about 'OPR' (Output Power Reduction) - The Primary Purpose of 'OPR' is to give you access to the Sound of 'Output Valve Distortion' at Reduced Volume Levels. 'OPR' will do Little or Nothing until the Output Valves are being Driven Hard and Producing 'Harmonic Distortion' - Then, it Rules!!
This is a Superb Amplifier and you WILL be Delighted with it's Performance - If not, I will give you your Money Back.
I Modify a Selection of Valve Amplifiers with Different Specifications -
Quant aux samples il me semble que tu trouveras cela sur le site, ms en gros tu peux le faire sonner de façon JTM ou alors plexi suivant les réglages...
Je crois que dans le forum quelques samples ont aussi été mis, la seule différence c'est que le mien fait en plus 10w au lieu de 5w...
