Hoffman 5f1/More Clean Headroom

[jamaio]

I built the Hoffman 5f1 2 years ago and the amp has performed well. I used a Fender Sidekick Reverb 35 as a donor for the cabinet and chassis. When I first built it I did not expect much and I bought a cheap speaker just to fill the hole, a Celestion Rocket 50. I started experimenting with different speakers, I have a Deluxe Reverb Cabinet with 2 Jensen C10Q speakers, I plugged those speakers into the 5f1 and the tone I get is awesome so I ordered a Jensen C12Q for the 5f1. The sweet spot for tone is with the volume at 6.5, however, there is more distortion then I like. I replaced the 12ax7 with a 12at7 and that cleaned up the distortion at the same volume level. I don't think I lost much volume or tone but I was wondering if there was a better way to smooth out the distortion, or maybe a better preamp tube. I am using a Fender Strat with single coil pickups plugged straight into the amp, using the neck and middle pickups. The tone I am looking for is tight lows, bright highs and scooped mids with a little crunch. I am not looking to be a rock star, I don't play with a band, just entertaining myself in my living room.

For reference I built the amp to Doug's specs: https://el34world.com/Hoffman/files/Hoffman_5F1.pdf

Here is a link to my build: http://el34world.com/Forum/index.php?topic=21444.msg227532#msg227532

[sluckey]

You're probably at the limit of clean with that amp. A different speaker can get some more clean listening volume. JBLs and Electro-Voice come to mind.

I got one of these a while back. Loud, clean, excellent low end and good high end. Mids are good too, but any crunch/breakup you get will be coming from that amp, not the speaker.

https://www.amazon.com/Electro-Voice-Unpowered-Speaker-Cabinet-EVM12LCLSC8/dp/B000Z33HYI/ref=sr_1_6?ie=UTF8&qid=1550342681&sr=8-6&keywords=evm+12l

I also have a Weber California 12 that has a good clean sound with tight bass, strong mids and clear highs. No breakup.

[jamaio]

You're probably at the limit of clean with that amp.

Thanks for the reply!! I thought that might be the case.

The Jensen C12Q I ordered will be in next week, I will see how it sounds. I may order a 5751 pre amp tube to try, it will pass the same current as the 12ax7 but with a gain factor of 70.

I have also tried using a TS-808 Tube Screamer with the gain set at 2, tone on max and the volume set at 7. I get more clean highs and sustain but less lows. I also have to have the amp volume set at 3 to keep distortion down.

I will let you know how it sounds with the new speaker and different tubes, 12at7 and 5751.

[sluckey]

12AU7 and 12AY7 are also candidates. I think the speaker is gonna do the trick for you. I have a C12N in my 5E3 and like it pretty good.

[Slimtim]

i second everything steve said.the ev speakers are great.had a 15l i'll kick myself forever for getting rid of.also i use a 12au7(6189 actually) in v1 in my ao35 alot.also switch out an old 5star 5751 sometimes.

[jamaio]

I think the speaker is gonna do the trick for you.

I finally found time to install my new speaker, Jensen C12Q8, and it sounds awesome. I am using the 12AX7, the low end is very punchy so I was able to turn the volume down to clean up the distortion without losing tone.

Thanks for the suggestions.

[jamaio]

Today I replaced the 12ax7 with a 5751, I tested the volume of both tubes with an SPL. I had a little more than 1 dB drop with the 5751, however, the distortion cleaned up nicely. I am able to get clean tones up to 7 on the volume, after that the natural breakup is very smooth. I cranked the volume to max, "12", and played the intro to "Smoke on the Water", the amp sounds awesome!! I am playing a Strat with single coil pickups, neck and middle, plugged straight into the amp.

I am very pleased with the new speaker and the 5751 preamp tube.