Can anyone explain, or help me find a resource explaining which types of components to use along the specific stages of an amplifier. I know resistors can be carbon film or metal film, and capacitors can be film, electrolytic or ceramic.
I'm a novice-level amp guy who is interested in building an amp. I have already successfully built a Ceriatone HRM50, but the board was preassembled. I think I'd like to build an easier design like maybe a bassman or plexi, but do it component by component. I can go through a schematic and find all the values to buy, but I'm a bit lost regarding exacty which types of those components I should be getting.
For example,...
- Are carbon film resistors ok to use throught the entire amp as long as their wattage rating is sufficient?... other than the larger wattage cement resistor on the screen grid.
- Are the types of caps solely determined by power requirements?... Electrolytics for powersupply & coupling, and ceramics for smaller audio signal voltages??
Any help would be appreciated.
Component type choices (Novice question)
Moderators: pompeiisneaks, Colossal
Re: Component type choices (Novice question)
I'll probably rub some people here the wrong way. It's a big tent; room for various opinions and thoughts. I suggest that you shouldn't be too concerned about it. Don't buy too cheap [1] and don't go overboard on the kind of expensive parts that have snake oil inside. (Snake oil <> mojo.)
[1] Too cheap: I'm not specifically talking about price point, but it's a real factor. Don't overspend. I suggest many of the inexpensive brands are more than good enough in a guitar amplifier. Remember, a guitar amp has a pretty narrow audio range. Some stuff really is too cheap/poor quality and some of it is counterfeit. A newbee may have trouble distinguishing. That is a reason to buy from a reputable source. If you use a place like Mouser, there might be a zillion items that meet your selection criteria, which can be very confusing. You will, however, get excellent pricing. The thing to remember is to be sure to get everything you need in one order. That one thing you omitted for which you need a second order, that costs $1, will cost you $15 with shipping.
As for carbon comp resistors, these can be problematic (noisy) and should be avoided as plate load resistors. IMO, metal film is a better choice for plate load. Otherwise, get what you like. You can build a very decent sounding amp with metal film and carbon film resistors. Carbon comp is harder to get these days and prices are rising. I'm not convinced they are worth the spend.
On your question about caps, yes, electrolytic caps of proper voltage rating are needed in the power supply and also fairly low voltage rating for cathode bypass and in the bias circuit. Other caps are generally whatever type of ordinary film caps you want to choose. The substrate varies: polystyrene, polypropylene, etc. Some swear there are tonal differences. I think you'd need to experiment to really know if *you* can hear a difference. Give yourself permission to buy the ones with the color you like (orange drop vs. yellow barrel vs. green chicklets, etc.) The brown ones aren't as pretty but probably aren't bad for your amp!
[1] Too cheap: I'm not specifically talking about price point, but it's a real factor. Don't overspend. I suggest many of the inexpensive brands are more than good enough in a guitar amplifier. Remember, a guitar amp has a pretty narrow audio range. Some stuff really is too cheap/poor quality and some of it is counterfeit. A newbee may have trouble distinguishing. That is a reason to buy from a reputable source. If you use a place like Mouser, there might be a zillion items that meet your selection criteria, which can be very confusing. You will, however, get excellent pricing. The thing to remember is to be sure to get everything you need in one order. That one thing you omitted for which you need a second order, that costs $1, will cost you $15 with shipping.
As for carbon comp resistors, these can be problematic (noisy) and should be avoided as plate load resistors. IMO, metal film is a better choice for plate load. Otherwise, get what you like. You can build a very decent sounding amp with metal film and carbon film resistors. Carbon comp is harder to get these days and prices are rising. I'm not convinced they are worth the spend.
On your question about caps, yes, electrolytic caps of proper voltage rating are needed in the power supply and also fairly low voltage rating for cathode bypass and in the bias circuit. Other caps are generally whatever type of ordinary film caps you want to choose. The substrate varies: polystyrene, polypropylene, etc. Some swear there are tonal differences. I think you'd need to experiment to really know if *you* can hear a difference. Give yourself permission to buy the ones with the color you like (orange drop vs. yellow barrel vs. green chicklets, etc.) The brown ones aren't as pretty but probably aren't bad for your amp!
Re: Component type choices (Novice question)
Aiken has a couple of pages where such topics are discussed, one's down at the moment but here's the wayback capture https://web.archive.org/web/20220520201 ... hnical-q-a
https://www.aikenamps.com/index.php/res ... -it-matter
https://www.aikenamps.com/index.php/res ... -it-matter
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Re: Component type choices (Novice question)
FWIW, Aiken is worth the read.
I wanted to mention something else. Nearly everyone builds to a budget. Few have the deep pockets to get all boutique parts. Spend your money on a good output transformer and good speaker. These will, IMO, make more of a difference that what kind of cap or resistor you choose.
I wanted to mention something else. Nearly everyone builds to a budget. Few have the deep pockets to get all boutique parts. Spend your money on a good output transformer and good speaker. These will, IMO, make more of a difference that what kind of cap or resistor you choose.
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Re: Component type choices (Novice question)
I can't agree more, especially the speaker. This is one of the biggest impact on tone that you can get...Phil_S wrote: ↑Wed Nov 16, 2022 5:03 pm FWIW, Aiken is worth the read.
I wanted to mention something else. Nearly everyone builds to a budget. Few have the deep pockets to get all boutique parts. Spend your money on a good output transformer and good speaker. These will, IMO, make more of a difference that what kind of cap or resistor you choose.
~Phil
tUber Nerd!
Re: Component type choices (Novice question)
What Phil said is my same experience. To add to that, I avoid ebay and Amazon for buying the cheap resistors and other parts. I trust Digikey, Mouser, and the amp parts vendors much more (Hoffman Amps, Tube Depot, Amplified parts, etc). There's a really good YouTube video comparing capacitor types and I couldn't hear one bit of difference between them, and the people in the video didn't seem to be able to tell the difference either. Getting the right voltage spec and capacitor value for a given area of the amplifier is much more important. I recently splurged for some new Celestion Creambacks in a 2 x 12 bottom for a new amp I just built. OMG they sound like pure heaven. Yes I spent about $320 for the pair but the sound I'm hearing is just ear candy. Why go to all the trouble of building an amp and then use some crappy speakers? So worth the money. Same for transformers. Picking the right spec for the transformer and good quality is the most important. You can go to YouTube and watch a lot of videos that compare sounds of different parts of the amp. That's how I picked my speakers. They do all the work for you. 