What tubes do you plan to use in your DHT?

decur · « **Reply #160 on:** 13 Feb 2018, 10:38 pm »

Kr px4 can be purchased at best300b.com

bernardo · « **Reply #161 on:** 14 Feb 2018, 11:03 pm »

I looked over the most recent threads and decided this is likely the best place to post this. I purchased a LIO DHT about a month ago over several other highly regarded preamps. I was wondering if any owners with the DHT option have tried Herbie’s Audio Lab Ultrasonic Rx-50 tube dampers on their 2A3 tubes and, if so, what was the difference they brought about.

jhrlrd · « **Reply #162 on:** 2 Mar 2018, 07:51 am »

i've heard good things about the KR PX-4 but has anyone tried the KR 300B?

Vinnie R. · « **Reply #163 on:** 2 Mar 2018, 05:42 pm »

Quote from: jhrlrd on 2 Mar 2018, 07:51 am

i've heard good things about the KR PX-4 but has anyone tried the KR 300B?

Hi jhrlrd,

I am only familiar with the KR PX-4, but I plan to attend the Munich Show in May and will meet with KR Audio,
and see if I can get a few of their other DHT's (like their 300B) to evaluate.

Once I do, I'll post my findings.

Best regards,

Vinnie

jhrlrd · « **Reply #164 on:** 2 Mar 2018, 08:12 pm »

Thanks Vinnie, I didn't know about the KR 300b until I saw an advertisement for it the other day. A little less expensive than the Tak 300bs.
I don't even have my used DHT yet and I'm already planning tubes to try!

ebag4 · « **Reply #165 on:** 3 Mar 2018, 08:00 pm »

An update on the Elrog 300Bs, I have noticed that they can ring, I believe this is what is considered to be microphonic. The ringining is most noticeable when you stop a loud passage. I may try a cover over the tubes to see if that makes any difference. Just wanted to throw this out there for anyone who may be considering the Elrog.

Best,
Ed

CCJ · « **Reply #166 on:** 4 Mar 2018, 10:57 pm »

Regarding KR, I have their PX-4 and 45. Both are excellent build quality. The PX-4, as many have mentioned before do about everything well with little noise or hum. They are reference tubes in my mind.

The 45s are much warmer with better base extension and bit more noise and hum than PX-4, but nowhere near as noisy as the EML 45-mesh I have. The KR-45 are comparable to the RCA circa 1950 NOS I have in sound and noise. I prefer the KR 45 sound and they are less noisy

Someday will write up a more detailed comparison of KR PX-4 and the assortments of the 45s I have

czubero · « **Reply #167 on:** 5 Mar 2018, 04:57 pm »

I have a friend who brought a pair of Elrogs 300B, a first batch, which have reported to be flawed but still working. These Elrog shines on the LIO, There is more 3d presence and the sound stage opens up a little bit more. Also Vocals are more fleshed. I could not imagine something better than the TAKS in my system until now. I also replaced the LIO fuses with SR blue which also slightly improve the bass and high extensions.

My question to Vinnie, based on my research of prior Elrogs failures: Is the current of LIO DHT Power Supply limited with soft start at Power up, or if you have implemented some sort of initial current limiting at start up?

I believe that above may help with longer tubes life, specially the Elrogs.

czubero · « **Reply #168 on:** 5 Mar 2018, 04:58 pm »

Hope the new Elrogs rev were built to last from not very pleasant prior reports!

Vinnie R. · « **Reply #169 on:** 5 Mar 2018, 06:41 pm »

Quote

I don't even have my used DHT yet and I'm already planning tubes to try!

Hi jhrlrd,

That's the spirit!

Quote from: ebag4 on 3 Mar 2018, 08:00 pm

An update on the Elrog 300Bs, I have noticed that they can ring, I believe this is what is considered to be microphonic. The ringining is most noticeable when you stop a loud passage. I may try a cover over the tubes to see if that makes any difference. Just wanted to throw this out there for anyone who may be considering the Elrog.

Best,
Ed

Hi Ed,

Yes, sounds like microphonics. Some DHT's are definitely more microphonic than others. Thanks for the info.

Quote

Regarding KR, I have their PX-4 and 45. Both are excellent build quality. The PX-4, as many have mentioned before do about everything well with little noise or hum. They are reference tubes in my mind.

The 45s are much warmer with better base extension and bit more noise and hum than PX-4, but nowhere near as noisy as the EML 45-mesh I have. The KR-45 are comparable to the RCA circa 1950 NOS I have in sound and noise. I prefer the KR 45 sound and they are less noisy

Someday will write up a more detailed comparison of KR PX-4 and the assortments of the 45s I have

Hi CCJ,

Thank you for posting about the KR 45's! Besides lower hum/noise, do you find anything else sonically that you prefer with the KR PX4 compared to the KR 45? Or do you prefer the KR 45 overall?

Quote

My question to Vinnie, based on my research of prior Elrogs failures: Is the current of LIO DHT Power Supply limited with soft start at Power up, or if you have implemented some sort of initial current limiting at start up?

Hi czubero,

Thanks for sharing your impressions of the Elrog 300B! This might be the DHT that I want to try next, especially since you prefer them to the TAK TA-300B in your LIO (an extremely formidable opponent!

).

LIO DHT PRE indeed has a soft-start circuit (in-rush current limiting for the cathodes), and is very kind to DHTs in general because we are using them in the linestage and NOT powering speakers, so they don't run nearly as hot as in a SET output stage. In fact, I really cannot think of any other circuit out there that you will get more life out of your DHT's than LIO DHT PRE. So when you get your new pair of ELROG 300B, you can expect them to last a very long time (yes, assuming they were manufactured well).

BTW - have you experienced any of the microphonics that ebag4 mentioned above with his ELROG 300B?

Thanks

Vinnie

czubero · « **Reply #170 on:** 5 Mar 2018, 11:30 pm »

Vinnie, Not at all, but will test at higher volumes and without the isolation foots.

jhrlrd · « **Reply #171 on:** 20 Mar 2018, 04:55 am »

Can anyone generalize that the 45's are more authoritative, with more solid tighter bass than the 300B or 2A3?
or is it brand dependent?

FullRangeMan · « **Reply #172 on:** 20 Mar 2018, 06:29 am »

Quote from: jhrlrd on 20 Mar 2018, 04:55 am

Can anyone generalize that the 45's are more authoritative, with more solid tighter bass than the 300B or 2A3?
or is it brand dependent?

In a power amp position or in a DAC?

Vinnie R. · « **Reply #173 on:** 20 Mar 2018, 03:13 pm »

Quote from: jhrlrd

Can anyone generalize that the 45's are more authoritative, with more solid tighter bass than the 300B or 2A3?
or is it brand dependent?

Quote from: FullRangeMan on 20 Mar 2018, 06:29 am

In a power amp position or in a DAC?

Hi jhrlrd,

I'm going to infer that since you posted on this forum, you are asking about such tubes as used in the LIO DHT PRE.

I would not generalize by saying that 45's have a tighter bass than the 300B or 2A3. It really depends
on the make/model of the tube. And if they are used tubes, their age will come into play as well (and how they
were treated, the circuit they were used in, etc).

Also - the circuit topology that the tube is used in will most certainly come into play, as well as the parts of that circuit.
Even the load of the following stage will have some influence over the overall sound (e.g. driving a power amp with a 10k input impedance vs. one with a 100k input impedance).

Everything matters - even the type of matter matters, and in general, maybe it is best to leave the generalizations to the generals?

(sorry - that was really bad but I couldn't resist!)

Cheers!

Vinnie

jhrlrd · « **Reply #174 on:** 20 Mar 2018, 06:57 pm »

Thanks Vinnie, yes in the LIO DHT

jhrlrd · « **Reply #175 on:** 26 Mar 2018, 10:24 pm »

I have an opportunity to purchase a new pair of Electro Harmonix 300b for
Around $200. Can anyone say they are better than the EH 2A3 that
Come with the LIO?

FullRangeMan · « **Reply #176 on:** 26 Mar 2018, 10:47 pm »

The Vinnie tubes are tested before shipping to custumer.

TomS · « **Reply #177 on:** 26 Mar 2018, 10:57 pm »

Quote from: jhrlrd on 26 Mar 2018, 10:24 pm

I have an opportunity to purchase a new pair of Electro Harmonix 300b for
Around $200. Can anyone say they are better than the EH 300B that
Come with the LIO?

The stock tubes are EH 2A3's.

jhrlrd · « **Reply #178 on:** 26 Mar 2018, 11:32 pm »

I realize what the stock tubes are. it was a typo.
Is it a waste of $200 to try the EH 300b ?

FullRangeMan · « **Reply #179 on:** 27 Mar 2018, 12:03 am »

Quote from: jhrlrd on 26 Mar 2018, 11:32 pm

I realize what the stock tubes are.
Is it a waste of $200 to try the EH 300b ?

He mean say 2A3 is a 2.5V tube and 300B is a 5V tube.
Not sure if the equip have a 2.5/5V option.