In-line preamps: why so many?

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gsbe

Member
Joined
Jun 16, 2012
Messages
9
Location
Winchester, VA
I’d love to see a comparison of all the inline preamp boxes (Cloudlifter, Royer, KlarkTeknik, Triton, sE, Soyuz, Crimson etc…).

Why are there so many - do they all have different designs? How can I determine which is “best” for the price?

Thanks for pointing me to any resources online that already exist that I have overlooked.
 
Why are there so many - do they all have different designs? How can I determine which is “best” for the price?
I think there is quite a big market for it, because a lot of people want to connect hip but output weak SM7 mics to their preamps built into their audio interfaces. All the streamers, twitchers, youtubers are going for SM7s because then their bad room acoustics don't stand out as much and it looks cool too.

Even my 13 year old niece insists on a SM7, because she is now a microphone expert (thanks to influencer marketing). The mentioned pre-preamps are also relatively easy to manufacture.
 
I think there is quite a big market for it, because a lot of people want to connect hip but output weak SM7 mics to their preamps built into their audio interfaces. All the streamers, twitchers, youtubers are going for SM7s because then their bad room acoustics don't stand out as much and it looks cool too.

Even my 13 year old niece insists on a SM7, because she is now a microphone expert (thanks to influencer marketing). The mentioned pre-preamps are also relatively easy to manufacture.
At this point I think people buy SM7's just because they see everyone else using them. I'd use a Heil PR40 100 out of 100 times over an SM7.
 
I’d love to see a comparison of all the inline preamp boxes (Cloudlifter, Royer, KlarkTeknik, Triton, sE, Soyuz, Crimson etc…).

Why are there so many - do they all have different designs? How can I determine which is “best” for the price?
I think like so many things in this business, as long as you choose a good one that gives you lots of clean gain, you're going to be fine.
 
I’d love to see a comparison of all the inline preamp boxes (Cloudlifter, Royer, KlarkTeknik, Triton, sE, Soyuz, Crimson etc…).

Why are there so many - do they all have different designs? How can I determine which is “best” for the price?

Thanks for pointing me to any resources online that already exist that I have overlooked.
Many of them are very similar. I wouldn't agonize over the differences if you just need some extra gain...pick the one closest to your needs snd price point and if there is something deficient about it it should be pretty easy to tell and return.

I'm speculating but wouldn't be surprised if the Klark technic is a straight clone too.
 
The Klark-Technik works just fine, and currently the 2 channel is on sale for about $60/shipped in the US. They're all mostly the same thing. Differences being input Z. Exceptions being the Mogaine which is a transformer step-up with active buffer.
 
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I’d love to see a comparison of all the inline preamp boxes (Cloudlifter, Royer, KlarkTeknik, Triton, sE, Soyuz, Crimson etc…).

Why are there so many - do they all have different designs? How can I determine which is “best” for the price?

Thanks for pointing me to any resources online that already exist that I have overlooked.

i got my cloud lifters originally for my ribbons but yes, also always use on Sm7’s too. They are just lil FET gain circuits-clean n fast. the Soyuz on the other hand has a ton of color to it by design. On some things its not so obvious, on others its night n day. Build your own-i think the schemo is pinned here somewhere. Or as others suggested, just go for the price point that suits you.
 
Correct me if I'm wrong, but isn't the 60db, -129 EIN gain of an average interface input sufficient for most purposes? What is the need for an in-line pre that may even be noisier than some interface pres? Maybe a ribbon would need more gain for spoken word, but who in this day and age is using a ribbon like that? An sm7b might be low gain but enough to need a booster? Probably not. I think the perceived need for in-line pres comes from the fact that the gain in most interface pres isn't linear along the trim pot, and the boost in gain at the very end leads to the impression of increased noise.
 
Correct me if I'm wrong, but isn't the 60db, -129 EIN gain of an average interface input sufficient for most purposes? What is the need for an in-line pre that may even be noisier than some interface pres? Maybe a ribbon would need more gain for spoken word, but who in this day and age is using a ribbon like that? An sm7b might be low gain but enough to need a booster? Probably not. I think the perceived need for in-line pres comes from the fact that the gain in most interface pres isn't linear along the trim pot, and the boost in gain at the very end leads to the impression of increased noise.

There are a lot of lower priced bus powered interfaces that will reveal their noise floor at higher gains with low output mics and low sources. Get gain externally before internal gain cranks internal crud. Likewise, the best place for them ever is at the end of a very long line before a low output mic, like an analog stage snake running through lots of power. Get level up before it sees the rest of the path.

The extra noise penalty can be insignificant in comparison. The K-T I measured recently, you can see where it's higher noise at apples to apples gain, but it's very slight and I'd have to say I might imagine more noise, or not, if I want to believe one way or the other.

input Ω - listening to some ribbons comparing it's 7K to a transformerless 2K, I also don't really hear any tonal change. Yamaha QL series preamps are 7K5, A&H SQ series are 5K. The ones that are 22K or higher might or might not do something for ya.

Good transformer pre's can measure much higher Z in the midband, and the impedance curve will affect a ribbon positively at times. You'd lose that sticking one of these things in between.
 
There are a lot of lower priced bus powered interfaces that will reveal their noise floor at higher gains with low output mics and low sources. Get gain externally before internal gain cranks internal crud. Likewise, the best place for them ever is at the end of a very long line before a low output mic, like an analog stage snake running through lots of power. Get level up before it sees the rest of the path.

The extra noise penalty can be insignificant in comparison. The K-T I measured recently, you can see where it's higher noise at apples to apples gain, but it's very slight and I'd have to say I might imagine more noise, or not, if I want to believe one way or the other.

input Ω - listening to some ribbons comparing it's 7K to a transformerless 2K, I also don't really hear any tonal change. Yamaha QL series preamps are 7K5, A&H SQ series are 5K. The ones that are 22K or higher might or might not do something for ya.

Good transformer pre's can measure much higher Z in the midband, and the impedance curve will affect a ribbon positively at times. You'd lose that sticking one of these things in between.
Impedance is a good point. However, are these interface pres really "obtaining" noise at high gain, or is the inherent noise merely more apparent? I'm actually rather inexperienced, so your learned wisdom would be much appreciated.
 
Impedance is a good point. However, are these interface pres really "obtaining" noise at high gain, or is the inherent noise merely more apparent? I'm actually rather inexperienced, so your learned wisdom would be much appreciated.
The only cases where I noticed a real improvement were:
  • Noisy lines between mic and pre
  • Microphones with unduly high impedance
I've never experienced it but I could think it would be helpful with a preamp that has not enough gain, or is very noisy.
It is known since ages that in order to provide the best S/N ratio, the first element in the chain must be the one with the lowest intrinsic noise. A typical FetHead, Cloudlifter... has an input noise of about -125dBu, when many preamps have a significantly better figure, particularly at high gain, so in many cases, if the preamp has not enough gain, it is better to put gain after it than before it.
Of course it supposes clean connections between all the elements of the chain.
Indeed, most preamps gain control are not that good in terms of resolution when used close to their maximum gain; that's where operability becomes dominant over pure performance.
Some people believe that turning a knob over the 4 o'clock position is bad practice.

There's a few other threads in this group where I explain why I had to use an in-line booster, basically because I had a case of both noisy lines and wrong impedance mic (2500 ohms instead of advertised 200). Originally I used a FetHead (1st version) and was not very pleased with the result.
I then decided to look at designing one, which had none of the Fethead issues. It does what I need and there are now about a hundred of them in use, apparently with great satisfaction.
Me, I just kept one, that I use only with said wrong Z mic.
The one I designed has an input impedance of 40 kohms, but I haven't noticed any sonic difference with some of the other preamps I have.
I agree that too low an input impedance is detrimental to the sonic quality. In particular, I had a GT "The Brick", which input Z is about 500 ohms and it muffles the sound of dynamic and ribbon mics. I also have a few variable-Z preamps and it is obvious that the low settings never result in good performance.
 
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My biggest problem is that this stuff is generally marketed towards the inexperienced podcasters, who faultlessly don't know much about audio production or theory. It seems like predatory marketing; creating a need where none exists. The podcasters don't NEED the in-line pres to produce good, clean audio. It may help, in certain cases, but not really in a way where it is worth the extra expenditure. True, getting an exact level with just the trim pot at that setting may take a little fiddling. But considering that we live in the age of free digital gain, what does a few db or even 5 matter? The audio's going to be processed and mixed anyway. Considering that podcasters might have less than 500 at best to spend on their audio equipment, convincing them to make an unnecessary expenditure which would constitute 20% or more of their budget, money they may just barely have, is just an example of people trying to milk every penny out of the streaming/influencer craze.
 
just an example of people trying to milk every penny out of the streaming/influencer craze.
I agree with most of your comment, however in-line boosters existed way before the podcast boom.
They came out from the observation that many ribbon mics did not sound right with preamps that had too low an input impedance. AEA came with their own preamp, insisting that its super high input impedance was the main cause of improvement, with which I don't disagree. It then triggered a search for ways of improving the input impedance of existing preamps, which could be achieved practically and cost-effectively by providing extra gain. Since advertising gain is even simpler than input impedance, that's the angle marketeers put forward.
 
I’d love to see a comparison of all the inline preamp boxes (Cloudlifter, Royer, KlarkTeknik, Triton, sE, Soyuz, Crimson etc…).

Why are there so many - do they all have different designs? How can I determine which is “best” for the price?

Thanks for pointing me to any resources online that already exist that I have overlooked.
there are so many because customers apparently are buying them....

JR
 

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