It is currently Mon Mar 16, 2020 8:29 am

All times are UTC - 7 hours



Post new topic Reply to topic  [ 92 posts ]  Go to page Previous  1 ... 3, 4, 5, 6, 7
Go to page Previous  1 ... 3, 4, 5, 6, 7
Author Message
Post subject: Re: Any opinions on the Fromel Electronics HRD amp mod?
Posted: Sat Apr 06, 2019 6:03 pm
Offline
Hobbyist
Hobbyist

Joined: Fri Sep 12, 2008 12:40 pm
Posts: 75
TimsAudio wrote:
Welcome back to the forum.
Changing C24 will cut bass, but will also kill mids and reverb.
If you need more gain from the first stage, a common mod is to go to a 220K plate resistor. This also gives a buit more bounce to the tone.
If you want touch sensitive breakup, change the cathode resistor, R5, from 1.5K to 2.7K, 3.3K, or 4.7K for increasing sensitivity to string pressure. It causes tube breakup by changing the center of the operating point of the tube.

would also recommend the TBV mod I posted last year.


Hello Tim

Recently I changed the R4 (plate resistor) from 100K to 180K (could not find a 220K as you recommended). Since I have a C1 2,2 uF you recommended to change R4 to 220K, but I want to lower C1 more, to 1 uF because my Les Paul still sounds a bit bassy. Should I change R4 to another value if I lower C1 again? If I find the 220K what difference will make it in the sound? Will it help to break up the amp earlier in clean mode, what will happen if I go up to 300K?


Top
Profile
Fender Play Winter Sale 2020
Post subject: Re: Any opinions on the Fromel Electronics HRD amp mod?
Posted: Sun Apr 07, 2019 5:05 am
Offline
Hobbyist
Hobbyist

Joined: Thu May 26, 2016 5:40 pm
Posts: 87
My opinion: After you do the mods, insert the right preamp tubes and speakers you have a very decent amp. And it shouldn't be judged next to vintage Fenders but viewed on its own merits.

One needs to have a tech go over the amp strengthing the welds, replacing the resistors at R78 & R79 if it's one of the early models. I gigged 2001 HRD for years, I had a tech remove the Drive channel and put a master volume for the clean. It was an excellent amp. Sold it (wish I didn't)

Acquired a HRDeluxe III in a trade, sent it off to a tech who moded it (probably close to what the IV now is) Dropped my favorite tubes in and replaced the Celestion 12p80 with an old Oxford 12T6 I had. This amp has extinguished any and all gas I've had for Deluxe Reverb (I know its a different tone stack but damn this amp sound good) Full service, both the clean and Drive channel are stage-worthy, right size, right weight... and hangs with my vintage Fenders (gets just as much practice and gig time as them)


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 92 posts ]  Go to page Previous  1 ... 3, 4, 5, 6, 7
Go to page Previous  1 ... 3, 4, 5, 6, 7

All times are UTC - 7 hours

Fender Play Winter Sale 2020

Who is online

Users browsing this forum: TimsAudio and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to: