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Helm Audio Bolt Review (Portable DAC & Amp)

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amirm

amirm

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Rottmannash

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Monoprice has a portable DAC/amp with 2 THX AAA 78 amp modules and a AKM 4493 chip for $299. And something called Dirac Sensurround II. 220 mW in 16 ohm, 340 mW in 32 ohm.

So THX seems to be expanding its offerings a bit.
 

Billy Budapest

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So who is it for really? Maybe some business deal, THX willing to get their brand out there, and Helm willing to try a AAA amp module on future products, and trying to get some « partnership, one stop, we not only provide amplification circuitry, but also stamp and measure your other products, or something like that. The THX new business model is hard to follow. I don’t know if it’s evolving, but before the first THX head amps where out, I know their licences and royalties where out of control expensive. I see it now on relatively inexpensive gear so it may have changed.
Helm does in fact sell a $199 amplifier featuring THX AAA circuitry. However, it is curiously designed to be an “in-line“ amplifier fed through a cellphone‘s (or DAP’s) headphone output. So, however good/bad the performance is of the cellphone’s analog output circuitry will be a limiting factor.

https://www.thx.com/blog/helm-launches-headphone-amplifier-with-thx-aaa/

https://helmaudio.com/products/db12

A very odd product.

1613447218829.jpeg
 

capslock

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I believe WolfX measured them, check out l7audiolabs.

Ok, thanks, found it. Nothing to write home about. The balanced DC04 sits at about -105 db, the unbalanced DC03 at -118 dB. Both have a phase wraparound issue that has been fixed with a firmware update that might have other issues (google translate does not do a good gob of translating the comments.

https://www.l7audiolab.com/f/measurement-of-ibasso-dc-03/
https://www.l7audiolab.com/f/measurement-of-ibasso-dc-04/
https://www.l7audiolab.com/f/ibassodc0304phasefixed/
 

GWolfman

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Guys, I've no idea what JohnYang1997 talking about, and we have no any confrontation as I know ;) I said that ESS cheating with specs, and this case isn't first.
The specs are likely based on best-case numbers in a desktop environment with clean/filtered power with much more power and short/minimized leads.
 

ZolaIII

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Let's face it CS is way above competition with its CS43131, CS43198 line's when it comes to power efficiency and the worst design so far mesured doesn't go under 106 dB SINAD. Cheap TempoTec Sonata HD Pro with all of it's flows is still king of the hill in this category. I would really like to see HiBy R3Pro (non Sabre - CS version) DAP measurements.
 

blse59

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At $80 you have the S8 which squeezes out a minuscule amount of more power with the 2V SINAD being over 10dB better.

I guess this premium is for MQA.
The Tempotec Sonata HD Pro, which I think is the same as the S8, is only $40 for the Android and $60 for the Android/iOS!
 

ZolaIII

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The Tempotec Sonata HD Pro, which I think is the same as the S8, is only $40 for the Android and $60 for the Android/iOS!
Well it got to 36~40$ at it's lowest and yes it's the same (same PCB and all on it).
 

IVX

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ZolaIII, actually, es9280/9281 datasheet promises 94mW consumption in "hifi mode 2", it is quite effective as well. Another point is interesting, the price of Meizu HiFi DAC in China reaches $13 i.e. the brand new unit in the original package, the same time es9280 based noname PCBA(populated and soldered PCB, you can buy such things and assemble your own "$99" DACs) about $20-30. It seems, wholesales price for the CL solution is noticeable less than ESS.
PS: However, es9280 is the single-chip solution when CL is the two-chips chipset, hence ESS has to be more expensive due to higher integration(easier production, even less size) if performances are comparable(that's is not really). To be honest, es9280/9281 integration isn't a top one, because external flash IC is required and 2 regulators 1.8/3.3v as well. As an example of full integration, I recollect Realtek ALC4050 which has 64KB flash onboard, ADC/DAC+HPA, all rails are internally implemented(5v only needed, and a few MLCCs) and core voltage 1.1V i.e. more advanced silicon process makes that chip superb power and cost effective($1). One bottleneck is there its DAC is completely garbage with DR 100db(A) and THD+N .01%
 
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ZolaIII

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@IVX well for the same lv of integration to keep thing's on pair CS43131 is equal to ES9028K2M (DAC and AMP) or ES9018K2M to CS43198 (no amp) but how ever you put it ESS is playing catchup and not very well. Simply CS43131 is very efficient and i think the Meizu dongle you mentioned is a champion regarding power efficiency metric (so far people did calculate for). I actually think CS43131 can even do a lot better, it's a complex design and every interface so far (we never got USB audio 3.0 finalised) is actually pulling it down. That's why I would like to more closely inspect it's performance on better SoM and without USB.

Best regards.
 

Billy Budapest

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Rottmannash

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The Tempotec Sonata HD Pro, which I think is the same as the S8, is only $40 for the Android and $60 for the Android/iOS!
I've heard it's a decent device.
 

noel_fs

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thanks for doing multiple impedances, could you do 150ohm instead of the 12ohm step
 

Palfim

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[QUOTE=" I would really like to see HiBy R3Pro (non Sabre - CS version) DAP measurements.[/QUOTE]

Me too. I compared the spec sheets on both versions, and the normal r3 pro cirrus version has way better thd values compared to their more expensive and hyped up "saber r3 pro". Hiby sometimes gives their specs on "unloaded" 32 ohm, which makes them look better...but If you look closely and compare loaded Vs loaded on the cs and ess specs, the CS variant scores WAY better on thd, snr and other values .except with a little less output power on the Cs side.

I was about to order the normal r3 pro CS to use as an usb DAC /amp/bt all in one device, sort of a qudelix5 but with better thd , and an integrated dap ontop....well but in the end I went with the e1da susumu 3k. You just can't beat this one, if you want no compromises. Who cares for bt and LTE. When I want to enjoy music I could care less for missing a phone call. It's even a plus to have no BT, as it's too easy to take phone calls while listening to music.....which sucks! People should take their time to really enjoy and honour good music, instead of being always available everywhere
And the guys from e1da show a lot of dedication, always on the hunt to improve more and more ...but don't hurry too much to release an even better Cirrus device, as I would have to switch again so soon after aquiring the awesome 9038s gen3 jk
 

ZolaIII

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Well @Palfim guess what? The @IVX is a E1DA designer. Even R3Pro uses old CPU and USB it's one of the better SoM's for such. I find a BT control of playback of content streamed or on device's storage as the most useful, practical you can leave it laying in your pocket and do it all on the mobile when it comes to HiBy Music (with DAP or any device with the app).
Best regards.
 

Palfim

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Well @Palfim guess what? The @IVX is a E1DA designer. Even R3Pro uses old CPU and USB it's one of the better SoM's for such. I find a BT control of playback of content streamed or on device's storage as the most useful, practical you can leave it laying in your pocket and do it all on the mobile when it comes to HiBy Music (with DAP or any device with the app).
Best regards.
That bt control thing is actually a good idea, since I can't get a stable 990kbps signal from too many 2,4ghz routers around me, but using it only for controlling is brilliant. Yeah , IVX's post are brilliant , providing slot of technical background from a manufactures view is invaluable .
With the e1da only weighting 10g and a nice flexible usb cable it should be comfortable enough , almost like wireless
 

0RF30

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I bought a Hidizs 8 and it was very good, but the physical quality was poor. There was some kind of problem with the connection between the telephone and the dongle, sometimes it worked and sometimes it did not, and the supplied cables and connectors were lousy. I sent it back and ordered a Hidizs 9 instead. It has even better specifications, and it is better built, but too late I realized that it also drains the battery in a smartphone very quickly. Now I use Hidizs 9 only for my desktop computer, but am thinking of giving Hidizs 8 a second chance.

I stopped using Hidizs S8 on my android phone for the same reason. Provided USB-C to micro USB cable is pure crap. I had to order an aftermarket USB-C cable for my E1DA 9038D and 9038GS3 (provided ones had no connection issues but were very stiff and and the metal part got lose in the plastic with time).
I got this one : https://fr.aliexpress.com/item/32961312907.html?spm=a2g0s.9042311.0.0.38156c37o8Q6Xk , and was so perfectly happy with that I ordered his USB-C to micro USB brother for the S8 : https://fr.aliexpress.com/item/1005002053361868.html?spm=a2g0s.9042311.0.0.38156c37o8Q6Xk .
No connection issues since, I can use my S8 mobile again, wich is nice, it's a great dongle (maybe a bit power shy for running power hungry headphones with strong EQ). The only real issue left in mobile use is maybe the physical volume controls. Buttons are easily triggered in your pocket or against clothes or external surfaces if you let the dongle lay on his cable. Increments are huge, so they're basically useless anyway, and it can be a very bad surprise for your ears if you're listening at a strong volume and increase it more by accident.

I now own Hidizs S8 and S9, E1DA 9038D, 9038GS3 and Powerdac V2, I'll maybe try to write a subjective comparative review about them, all are great devices, all with their own strengths and weaknesses (in comparison to the others, I think most people will be happy with any of them, I enjoy all of them in different ways). I have eyes on Luxury & Precision recently bread dongles, I usually like well implemented Cirrus Logic dacs, the ones I have and had always provided a nice balance between details, bass body, imaging and separation. From the previously mentioned dongle, the S8 is maybe the most balanced regarding these points.
 
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