Hafler Preamplifiers - DH101 vs. 915

[bcrescen]

I have been using the DH101 for sometime and have found it favorable to my PAS2, Phase Linear 4000 S2, and a Harmon Kardon HK725. The DH101 is stock except I removed the tone controls. My current amplifier is a Tripath based AudoSource I purchased from Ebay but I also switch out to Magnavox or Fisher console tube amps.

I recently picked up the the Hafler 915 and at first thought I liked it better than the DH 101. It sounded pretty good with the AudioSource amp and I liked the extra inputs and headphone jack.

When I switched to my Fisher 440-A console amp (EL84 PP) my wife commented that the bass sounded muddy. After listening a while longer I had to agree. I switched to my Maggie EL84 SE amp (AMP 196-00) and while better the low end was still a little muddy.

We alternated the 101 and 915 with the Maggie SE and both agreed that the 101 sounded better. Bigger sound stage, more detailed, and tighter bass.

I then switched back to the AudioSource amp and did the same comparison. The 915 sounded better with the solid state amp and I found it difficult to choose which preamp I like better.

There isn't much info out there on the 915 but I read that it is supposed to have a tube like sound. Maybe when added to a tube amplifier it is too much.

Any thoughts or confirmation on what I'm hearing? I would also be interested in any tweaks or mods for the 915.

Bruce

 

[john65b]

I have a nice Hafler 945 Jfet preamp that I like very much. I would like to have an Hafler Iris someday (if I can ever find one).

Anyway, the 945 sounds very good. I picked it off a friend when it was not working. I replaced the relay and it fired right up. My friend was none too happy about me fixing it after hearing it. He wanted it back, but no can do. Sounds very clean and snappy.

I slightly prefer my Audionote M7 clone over it, but for $0, I can't help but like it alot.

I don't know why, but I prefer the sound of a tube pre on a solid state amp, and a solid state pre on a tube amp the best.

 

[nigelwright7557]

I don't know why, but I prefer the sound of a tube pre on a solid state amp, and a solid state pre on a tube amp the best.

Me too.
I play guitar and run a mobile disco so have a 4 channel mixer with an ECC83 valve (tube).
I have 3 inputs that go into the second stage of the ECC83.
Teh first stage of the ECC83 is a mic preamp that is amplified then mixed into the second stage with the other 3 channels.
I like the warmer sound of the valve.

I plug my guitar into the mic input and it really rocks.

 

[bcrescen]

Thanks for the input. Might be time to pop the lid and see what's inside the 915. Good to hear that others like solid state preamps with tube power amps.

 

[mlloyd1]

you can go to the hafler site and download manuals which contain schematics for both the 915 and DH101.

i like the 915 also. i wanted a used one, but never found one. so i ended up sort of making my own.
🙂

mlloyd1

Thanks for the input. Might be time to pop the lid and see what's inside the 915. Good to hear that others like solid state preamps with tube power amps.

 

[bcrescen]

Thanks for the advice. Did you use 4700uf caps in the powersupply and do you think a larger size might make a difference in the bass response?

 

[mlloyd1]

i generally use at least 3 times that amount of capacitance in my preamp power supplies, although it is spread out, not all in one place. i suspect there are other areas that would have a more noticeable impact on bass response ...
for example any coupling caps in the chain ...

mlloyd1

Thanks for the advice. Did you use 4700uf caps in the powersupply and do you think a larger size might make a difference in the bass response?