Bottlehead Crack, what makes it special?

[hoangdo]

Hello everyone
I’m new to the audiophile world and I’m looking for an amp that can work well with my HD650 headphones. After researching from many different sources, I found that the Bottlehead Crack is one of the most highly recommended one. I also looked deeper into the Bottlehead Crack, and I really don’t understand how it can bring the HD650 to a the new level like everyone says. The components are very ordinary (for example, the tubes are just regular types) and the manual assembly — how could that possibly be better than other devices that are assembled by machines and professional technicians with higher-end components? I’m sorry if this is a silly question, but in my country (Vietnam) I almost can’t find a Bottlehead Crack to experience it for myself, so I have to ask what might seem like a laughable question here.

 

[respice finem]

see here

Bottlehead Crack Headphone Amplifier Kit Review

This is a review and detailed measurements of a (built) Bottlehead Crack Tube headphone amplifier. It was sold from one member to another and kindly sent to me in between for testing. The version I have has the "speed ball" current source which brings its cost up to US $430. The original...

www.audiosciencereview.com

 

[majingotan]

It’s both output impedance and tube harmonic distortion characteristics that some people prefer over the highly accurate and correct sounding well implemented solid state amps.

Best approach is to always EQ to your tastes rather than buying blind and not preferring the BH Crack coloration to the sound

 

[DVDdoug]

What's wrong with what you have? What are you trying to change or improve? Your headphones are highly regarded.

All headphones and speakers sound different (better or worse) but most electronics are better than human hearing unless you overdrive and amplifier (or something) into clipping/distortion.

It's not "hard" or expensive to build a good headphone amp. You usually only need less than 1 Watt and you certainly don't need 1950s tube technology.... Most of the cost of a headphone amp goes into the case, connectors, controls, power supply, etc. And it's a "specialty item" so the marketing & distribution costs are high compared to high-volume products like TVs & AVRs. The actual amplifier electronics are cheap (at least with modern solid state electronics).

If your headphones aren't going loud enough you need an amplifier with more output voltage. (The HD650 is higher-than-average impedance and that generally means less sensitivity.

According to the review here, your headphones are slightly lacking in bass so simply boosting the bass may be the "solution". And boosting the bass may also require more output from the headphone amp.

I’m new to the audiophile world

Beware!!! MOST of the audiophile community is nuts! This is one of the few scientific-rational resources. Most "audiophiles" and reviewers don't trust measurements and "don't believe in" blind listening tests. They are also often fascinated with tubes, vinyl records, and other outdated technology. And, a higher price in the audiophile market tends to make it more desirable, even if most can't afford it!

Amir (our host here who does most of the reviews) doesn't do blind listening tests (it's VERY time consuming to do it properly and not everybody has the same hearing ability) but he backs-up what he hears with measurements.

See Audiophoolery. He talks about the few REAL characteristics of sound quality and it will help you to spot (and hopefully ignore) all of the nonsense terminology about the "sound" of different amplifiers, etc. Also see What is a blind ABX test?

The components are very ordinary (for example, the tubes are just regular types) and the manual assembly — how could that possibly be better than other devices that are assembled by machines and professional technicians with higher-end components? I’m sorry if this is a silly question

It's not a silly question, especially with all of the "audiophile nonsense" you might be reading...

IMO - tubes are dumb. There is no technical advantage.*
You can make a good amplifier with tubes OR solid state electronics. But it's more expensive to to make one with tubes. Tube power amps require an output transformer to drive the low impedance of speakers, and that adds even more cost and difficulty. Impedance can be an issue with tube headphone amps too, but your headphones are high-enough impedance that it shouldn't be a problem.

The tubes don't have to be "special", just appropriate for the application. The important thing is a "good" circuit design. Tubes, transistors, MOSFETs and IC's all have tolerances and variations and the engineer's job is to make the amplifier work properly as long as the parts are in-spec. Some tube amps are NOT well designed so you can get variations swapping tubes, or as the tubes age, etc.



* Guitar players tend to favor tube amps, especially for for the way they sound when over-driven into distortion. (You're not supposed to over-drive your hi-fi amp.) And guitar amps are not intended to be high-fidelity. You wouldn't want to hear the whole band through a distorted guitar amp! And they don't all sound the same so most guitar players have their favorite guitar and favorite amp. Of course, they make solid state guitar amps that distort like tubes, and software to simulate the sound of different amps & cabinets, but most musicians are passionate about their instrument and equipment.

 

[hoangdo]

see here

Bottlehead Crack Headphone Amplifier Kit Review

This is a review and detailed measurements of a (built) Bottlehead Crack Tube headphone amplifier. It was sold from one member to another and kindly sent to me in between for testing. The version I have has the "speed ball" current source which brings its cost up to US $430. The original...

www.audiosciencereview.com

Thanks, it is very nice post

 

[hoangdo]

It’s both output impedance and tube harmonic distortion characteristics that some people prefer over the highly accurate and correct sounding well implemented solid state amps.

Best approach is to always EQ to your tastes rather than buying blind and not preferring the BH Crack coloration to the sound

Yes, those are general opinions about tube amps. What I don’t understand is why the Bottlehead Crack is rated so highly, while other tube amps in the same segment like those from Darkvoice or Woo, etc., aren’t . And thank you for your advice, that really is a good idea to adjust the EQ, but honestly I don’t know whether the sound quality in a certain frequency range would actually be as good using EQ compared to the sound that the amp itself gives without the need of EQ

 

[oleg87]

Probably most likely because the HD650 is flattered by the Crack's sky-high output impedance.
If the idea of DIY tube amp doesn't appeal to you, you certainly don't need one to get the HD650 to sound good.

 

[hoangdo]

Thank you very much for your sincere advice and all the detailed information you’ve shared. I really trust careful and neutral advice like yours. My current issue is that I want to upgrade the amp for my headphones. I’m using a Topping DX3 Pro Plus DAC/AMP, and I’m not completely satisfied with it because I still feel it lacks bass, which I think is pretty noticeable, and even with higher frequencies, I’m not really happy with the level of detail. There are many instruments (sorry, I don’t know their exact names) that I can hear very clearly at a live concert or through a good speaker setup, but they feel rather shallow when I listen on my HD650 headphones with my current DAC/AMP. I’ve read Amir’s review of the Bottlehead Crack, and I think he’s like you, preferring solid-state amps over the Bottlehead Crack. After reading both your posts, I completely agree with that. If I bought a Bottlehead Crack kit and added shipping to Vietnam, the price would be about the same as a Topping A90. The most obvious benefit of the Topping A90 compared to the Bottlehead Crack is that it will work well with many types of headphones, so I’ll try pairing my headphones with a Topping A90 amp first to decide whether to upgrade my amp or not. Once again, thank you very much.
About my question: why is the Bottlehead Crack rated so highly? I think it’s partly the reward that comes from the DIY process. Maybe I would love it more and be biased toward it if I spent a weekend building a complete amp myself from individual components

 

[unpluggged]

the sound that the amp itself gives

A good amp does not "give" any sound.

My recommendation is to get the Qudelix 5K and a 2.5 mm balanced cable for your phones and make use of the EQ.

 

[oleg87]

About my question: why is the Bottlehead Crack rated so highly? I think it’s partly the reward that comes from the DIY process. Maybe I would love it more and be biased toward it if I spent a weekend building a complete amp myself from individual components

That certainly is a factor. I wouldn't underestimate the power of sighted bias induced self-reinforcing groupthink either.
I've listened to the Crack with my HD600 and it sounds perfectly nice... but it's just an amp. If you want more bass, save yourself a heap of money and EQ in more bass.

 

[Soandso]

Because it appeared at a point in time when the revival of tube amplifiers as something that guys could assemble happened to arise in the era of internet access. With group support for assistance it became a totem replete with vast minutia to socially bond over. This mutually reinforced a sense of achievement derived from the physical product which reflexively garnered elevated praise for reliably working as an amplifier.

 

[kemmler3D]

I’m using a Topping DX3 Pro Plus DAC/AMP, and I’m not completely satisfied with it because I still feel it lacks bass, which I think is pretty noticeable, and even with higher frequencies, I’m not really happy with the level of detail.

This will be due to the headphones themselves, not the DAC/AMP. If you want to correct that, EQ is the best way.

I don’t know whether the sound quality in a certain frequency range would actually be as good using EQ compared to the sound that the amp itself gives without the need of EQ

The difference might come into play if the tubes are creating nonlinear / dynamic effects rather than a simple change to the frequency response. The problem with this type of "enhancement' is it's expensive, and you have no control over what it actually does to the sound, you just have to plug and pray.

For a static change to the signal (i.e. doesn't change depending on input) I believe the changes to "certain frequency ranges" would be mathematically and practically the same.

A long way of saying, these two methods may not sound exactly the same, but the *quality* of the change that you actually intend to make will be exactly the same.

EQ is cheap / free, you should just try it and see how you like it, before spending real $$ on new gear.

 

[DenverW]

Thank you very much for your sincere advice and all the detailed information you’ve shared. I really trust careful and neutral advice like yours. My current issue is that I want to upgrade the amp for my headphones. I’m using a Topping DX3 Pro Plus DAC/AMP, and I’m not completely satisfied with it because I still feel it lacks bass, which I think is pretty noticeable, and even with higher frequencies, I’m not really happy with the level of detail. There are many instruments (sorry, I don’t know their exact names) that I can hear very clearly at a live concert or through a good speaker setup, but they feel rather shallow when I listen on my HD650 headphones with my current DAC/AMP. I’ve read Amir’s review of the Bottlehead Crack, and I think he’s like you, preferring solid-state amps over the Bottlehead Crack. After reading both your posts, I completely agree with that. If I bought a Bottlehead Crack kit and added shipping to Vietnam, the price would be about the same as a Topping A90. The most obvious benefit of the Topping A90 compared to the Bottlehead Crack is that it will work well with many types of headphones, so I’ll try pairing my headphones with a Topping A90 amp first to decide whether to upgrade my amp or not. Once again, thank you very much.
About my question: why is the Bottlehead Crack rated so highly? I think it’s partly the reward that comes from the DIY process. Maybe I would love it more and be biased toward it if I spent a weekend building a complete amp myself from individual components

You're absolutely correct on the 'proud papa' factor of building and then listening to an amp. One of the benefits of building a kit such as the crack is the learning process of amp building, soldering, and trouble shooting. Some people find the building process fun, others don't. If you enjoy it, the things you learn carry over to other areas such as making cables, or repairing gear that fails.

As far as why the amp is regarded so highly outside of this site, I don't think you're going to get a satisfying answer. There is some great advice above regarding tube amps vs solid state. So, if that's the case, why is the crack so popular elsewhere? It is short sighted and dismissive to label everyone who enjoys it as an "audiophool." The only way you're going to answer this question for yourself is to try it and determine if you enjoy it. The amp does add harmonic distortion, so if you want a pure representation of the signal you're listening to then take that into consideration. Does the coloration actually make a more pleasant listening experience on your HD650? Only you can answer that for yourself.

 

[Phatfish]

I'll chime in and say that it was actually Amir's positive subjective impressions that sold me on building my bottlehead crack. A good friend of mine once declared that a hobby wasn't just buying stuff, and I'll parrot that here adding that listening to something you built yourself AND sounds good is addictive/intoxicating. I think that is a big reason this kit is so well received. Currently building my 5th bottlehead kit and I've been thrilled with the experience and support from them. Cheers.